{"id":1255350582484893700,"conversation_id":"1255343846445195266","created_at":1588133876000,"date":"2020-04-29","time":"04:17:56","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"Another thing to recognize is that this model was presumably created with a different purpose than the IHME model. The IHME model was first and foremost intended to forecast peak hospital need. This model seems more focused on forecasting past the peak of the curve.","mentions":[],"urls":[],"photos":[],"replies_count":1,"retweets_count":6,"likes_count":94,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1255350582484893697","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1255347456746967000,"conversation_id":"1255343846445195266","created_at":1588133131000,"date":"2020-04-29","time":"04:05:31","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"Unlike the IHME model, Youyang Gu's model tries to predict what happens beyond the current period of intense social distancing. This allows him to avoid the IHME's ridiculously low estimates (with tight confidence bounds) of June deaths.","mentions":[],"urls":[],"photos":[],"replies_count":5,"retweets_count":29,"likes_count":173,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1255347456746967042","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1255346772525944800,"conversation_id":"1255343846445195266","created_at":1588132968000,"date":"2020-04-29","time":"04:02:48","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"(Though above my pay grade, I'd be curious how this would compare to Bayesian MCMC approaches.)\n\nRather than employing a formal model selection procedure the system avoids overfitting using cross-validiation methods. This is critical; the approach seems sensible enough to me.","mentions":[],"urls":[],"photos":[],"replies_count":6,"retweets_count":7,"likes_count":110,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1255346772525944835","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1255345035526180900,"conversation_id":"1255343846445195266","created_at":1588132554000,"date":"2020-04-29","time":"03:55:54","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"A few preliminary impressions. First, I can be a bit of an ML skeptic. But in this case, don't let the \"machine learning\" text fool you into thinking this is snake oil. There is a solid mechanistic SEI(R)S foundation to everything here. ML is used for parameter inference on top.","mentions":[],"urls":[],"photos":[],"replies_count":3,"retweets_count":5,"likes_count":114,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1255345035526180868","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1255194381247602700,"conversation_id":"1254881664552939520","created_at":1588096635000,"date":"2020-04-28","time":"17:57:15","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"I guess that's good, but I still disagree with the piece.\n\nMocking someone for making an error is one thing. Calling them out for going on FOX News to promote a study with known major statistical flaws using some participants solicited under false premises? Entirely permissible.","mentions":[],"urls":[],"photos":[],"replies_count":13,"retweets_count":48,"likes_count":415,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1255194381247602688","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1254972254351274000,"conversation_id":"1254950807428050945","created_at":1588043676000,"date":"2020-04-28","time":"03:14:36","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"3. Given that only 1.5% of the 3300 serotype tests they conducted were positive, we can now establish 1.95% as a 95% confidence upper bound on the false positive rate of their test. \n\nThat's all we can do, and it's irrelevant to the spin they're pushing, but it's not nothing.","mentions":[],"urls":[],"photos":[],"replies_count":23,"retweets_count":19,"likes_count":264,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1254972254351273985","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1254972253617270800,"conversation_id":"1254950807428050945","created_at":1588043676000,"date":"2020-04-28","time":"03:14:36","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"2. At some point I think I even called the study useless.\n\nI want to apologize to the study authors for that. Today I realized it's not useless at all. \n\nIt does some thing very useful. Maybe not what the authors intended, but useful nonetheless.","mentions":[],"urls":[],"photos":[],"replies_count":6,"retweets_count":5,"likes_count":103,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1254972253617270784","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1254888286092275700,"conversation_id":"1254881664552939520","created_at":1588023656000,"date":"2020-04-27","time":"21:40:56","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"You know if he'd just asked nicely, I probably could have helped him place the piece where people would care, in Quillette.","mentions":[],"urls":[],"photos":[],"replies_count":18,"retweets_count":19,"likes_count":641,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1254888286092275712","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1254881664552939500,"conversation_id":"1254881664552939520","created_at":1588022078000,"date":"2020-04-27","time":"21:14:38","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"So today the former dean of Harvard Medical School wrote an OpEd in a leading health publication about I'm \"silencing\" an endowed chair at Stanford Medical School by opining on twitter that his latest work is bullshit. \n\nHow's your day going?","mentions":[],"urls":[],"photos":[],"replies_count":175,"retweets_count":202,"likes_count":2457,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1254881664552939520","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1254860839485452300,"conversation_id":"1254856359201239042","created_at":1588017112000,"date":"2020-04-27","time":"19:51:52","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"9. Finally we address the risk of privacy unraveling if the opt-in apps become required de facto as stores, employers, etc. begin to require proof of health status.","mentions":[],"urls":[],"photos":[],"replies_count":2,"retweets_count":17,"likes_count":66,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1254860839485452288","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1254860594680705000,"conversation_id":"1254856359201239042","created_at":1588017054000,"date":"2020-04-27","time":"19:50:54","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"8. We also discuss privacy concerns, and the seriously (in our opinion) risks associated with malicious use by griefers, trolls, political operatives, foreign adversaries, in \"civil disobedience\", etc.","mentions":[],"urls":[],"photos":[],"replies_count":2,"retweets_count":16,"likes_count":67,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1254860594680705024","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1254860220204896300,"conversation_id":"1254856359201239042","created_at":1588016965000,"date":"2020-04-27","time":"19:49:25","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"7. Even if you flag only the close contacts, people in areas with reasonable disease prevalence may still be getting multiple self-quarantine requests over the course of an epidemic. How many false alarms until people simple ignore them?","mentions":[],"urls":[],"photos":[],"replies_count":6,"retweets_count":23,"likes_count":108,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1254860220204896256","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1254859893208567800,"conversation_id":"1254856359201239042","created_at":1588016887000,"date":"2020-04-27","time":"19:48:07","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"6. If you flag only the close contacts, you'll miss a lot of the transmissions. If you flag the fleeting contacts, people will face a constant and non-actionable stream of exposure warnings unless disease prevalence is very low.","mentions":[],"urls":[],"photos":[],"replies_count":5,"retweets_count":24,"likes_count":81,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1254859893208567809","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1254859089642877000,"conversation_id":"1254856359201239042","created_at":1588016695000,"date":"2020-04-27","time":"19:44:55","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"5. ...and (2) an actual contact occurs but transmission does not. Though the distribution is broad, people have on average about 12 close contacts (protracted conversation and/or touch) per day, and far more fleeting contacts.","mentions":[],"urls":[],"photos":[],"replies_count":3,"retweets_count":21,"likes_count":65,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1254859089642876928","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1254859088908828700,"conversation_id":"1254856359201239042","created_at":1588016695000,"date":"2020-04-27","time":"19:44:55","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"4. From an epidemiological perspective, I have serious concerns. Two kinds of false positives will be frequent. (1) Interactions with minimal chance of transmission are treated as contacts, e.g. when a wall is between the two users, or when PPE is in use...","mentions":[],"urls":[],"photos":[],"replies_count":5,"retweets_count":30,"likes_count":97,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1254859088908828672","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1254858099703165000,"conversation_id":"1254856359201239042","created_at":1588016459000,"date":"2020-04-27","time":"19:40:59","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"3. Digital contact tracing has been much-heralded as a way to escape from the current lockdown, and there is a Google-Apple collaboration underway to provide the API necessary for third party app developers to create appropriate software.\n\nBut....","mentions":[],"urls":[],"photos":[],"replies_count":1,"retweets_count":14,"likes_count":46,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1254858099703164929","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1254857723386065000,"conversation_id":"1254856359201239042","created_at":1588016370000,"date":"2020-04-27","time":"19:39:30","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"2. The basic idea behind digital contact tracing is to have smart phones talk to one another continually, in what are hopefully privacy-preserving ways to track contacts between users. If a user tests positive, contacts of that person are then notified.","mentions":[],"urls":[],"photos":[],"replies_count":3,"retweets_count":13,"likes_count":49,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1254857723386064896","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1254846056556163000,"conversation_id":"1254841153968472070","created_at":1588013588000,"date":"2020-04-27","time":"18:53:08","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"Protracted safety assessment is essential. A safety mishap could generate sufficient vaccine distrust that we could lose not only protection from COVID19, but also measles, pertussis, and other safely vaccine-preventable diseases.","mentions":[],"urls":[],"photos":[],"replies_count":6,"retweets_count":6,"likes_count":109,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1254846056556163077","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1254531721887748000,"conversation_id":"1254500412641533952","created_at":1587938645000,"date":"2020-04-26","time":"22:04:05","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"To be clear, it's not the trolls that get to me (though the combo of Russian MAGA trolls and Elon fanboys is a wild ride). \n\nNo, it's seeing Elon Musk, who easily has the background to see through that BS Bakersfield claim, using his massive platform to amplify misinformation.","mentions":[],"urls":[],"photos":[],"replies_count":36,"retweets_count":52,"likes_count":520,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1254531721887748096","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1254500412641534000,"conversation_id":"1254500412641533952","created_at":1587931180000,"date":"2020-04-26","time":"19:59:40","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"That's enough internet for me.","mentions":[],"urls":[],"photos":[],"replies_count":26,"retweets_count":16,"likes_count":369,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1254500412641533952","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1254487453131366400,"conversation_id":"1254481543759683584","created_at":1587928090000,"date":"2020-04-26","time":"19:08:10","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"And yet that 0.14% lower bound is nearly *five times as high* as the 0.03% that the Bakerfield duo are claiming. They've used absurd methodology to arrive at an implausible number.\n\nIf the pandemic were not so severely politicized, this would be a non-issue from the start.\n\n/fin","mentions":[],"urls":[],"photos":[],"replies_count":238,"retweets_count":476,"likes_count":3930,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1254487453131366402","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1254487383417909200,"conversation_id":"1254481543759683584","created_at":1587928074000,"date":"2020-04-26","time":"19:07:54","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"That gives us a lower bound on the death rate in New York. Not an estimate, a lower bound. \n\nThe death rate for infected people is obviously higher than 0.14%, because not everyone in New York has been infected.","mentions":[],"urls":[],"photos":[],"replies_count":33,"retweets_count":217,"likes_count":1592,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1254487383417909249","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1254487289721323500,"conversation_id":"1254481543759683584","created_at":1587928051000,"date":"2020-04-26","time":"19:07:31","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"Moreover the estimate does not pass even a basic plausibility check. \n\nIn New York City, 12,067 people are known to have died from the virus, out of a population of 8.4 million. \n\nThis is a rate of 0.14% of all people. Not just infected people. All people.","mentions":[],"urls":[],"photos":[],"replies_count":80,"retweets_count":340,"likes_count":1971,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1254487289721323521","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1254484809746792400,"conversation_id":"1254481543759683584","created_at":1587927460000,"date":"2020-04-26","time":"18:57:40","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"Estimating that fraction infected from patients at an urgent care facility is a bit like estimating the average height of Americans from the players on an NBA court. \n\nIt's not a random sample, and it gives a highly biased estimate.","mentions":[],"urls":[],"photos":[],"replies_count":30,"retweets_count":431,"likes_count":2718,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1254484809746792449","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1254484507320676400,"conversation_id":"1254481543759683584","created_at":1587927388000,"date":"2020-04-26","time":"18:56:28","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"The problem with this approach is that during a pandemic, the people who come into an urgent care clinic are not a random sample of the population. \n\nA large fraction of them are coming in precisely because they suspect that they have the disease.\n\nThis generates sampling bias.","mentions":[],"urls":[],"photos":[],"replies_count":80,"retweets_count":412,"likes_count":2967,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1254484507320676352","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1254484138838515700,"conversation_id":"1254481543759683584","created_at":1587927300000,"date":"2020-04-26","time":"18:55:00","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"Using that 12% infected figure, and a known 1400 deaths in California, they assume 1400 out of 4.7 million have died. That gives them an infection fatality rate of 0.03%.  That is, they think that if 10,000 are infected, 3 will die on average.","mentions":[],"urls":[],"photos":[],"replies_count":31,"retweets_count":170,"likes_count":1118,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1254484138838515712","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1253883244656750600,"conversation_id":"1253882222685249536","created_at":1587784036000,"date":"2020-04-25","time":"03:07:16","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"So far we are making very little progress and testing has stalled out around 150,000 tests per day nationwide. \n\nThis is absolutely inadequate.","mentions":[],"urls":[],"photos":[],"replies_count":6,"retweets_count":41,"likes_count":179,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1253883244656750593","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1253809939102920700,"conversation_id":"1253809939102920704","created_at":1587766558000,"date":"2020-04-24","time":"22:15:58","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"So is it cool if Stanford PhDs just list their bachelor's degree and postdoctoral experience? Asking for a friend.","mentions":[],"urls":[],"photos":[],"replies_count":17,"retweets_count":7,"likes_count":194,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1253809939102920704","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1253218927527620600,"conversation_id":"1253151333646917632","created_at":1587625650000,"date":"2020-04-23","time":"07:07:30","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"Thank you to all for your support and encouragement. I want to stress that while a month ago I was finding this hostility to be emotionally taxing, I'm mostly past that.\n\nMy fear tonight is for how we can solve the collective problem this pandemic poses while we so badly divided.","mentions":[],"urls":[],"photos":[],"replies_count":51,"retweets_count":48,"likes_count":1116,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1253218927527620613","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1253151333646917600,"conversation_id":"1253151333646917632","created_at":1587609535000,"date":"2020-04-23","time":"02:38:55","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"I know I should be so far over this, but tonight I'm again reeling at the number of people who think my concern over the COVID-19 pandemic arises from some kind of radical leftist ideology.","mentions":[],"urls":[],"photos":[],"replies_count":165,"retweets_count":407,"likes_count":3272,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1253151333646917632","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1253122350855278600,"conversation_id":"1253121855231127552","created_at":1587602624000,"date":"2020-04-23","time":"00:43:44","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"'Je suis epidemiologiste'","mentions":[],"urls":[],"photos":[],"replies_count":9,"retweets_count":10,"likes_count":170,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1253122350855278594","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1252712330661515300,"conversation_id":"1252712330661515265","created_at":1587504868000,"date":"2020-04-21","time":"21:34:28","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"I'm trying to write something about how to evaluate #COVID19 research papers.\n\nCan anyone suggest examples (ideally with justification) of COVID papers that were published in good journals but obviously never should have seen the light of day?\n\n(DMs open if you prefer)","mentions":[],"urls":[],"photos":[],"replies_count":24,"retweets_count":32,"likes_count":125,"hashtags":["#covid19"],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1252712330661515265","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1252532314715811800,"conversation_id":"1252532314715811842","created_at":1587461949000,"date":"2020-04-21","time":"09:39:09","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"Infectious disease epidemiologists find ourselves in the odd position of criticizing as irresponsible claims that we desperately hope to be true.","mentions":[],"urls":[],"photos":[],"replies_count":31,"retweets_count":346,"likes_count":1924,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1252532314715811842","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1252080941377261600,"conversation_id":"1252075528711860224","created_at":1587354333000,"date":"2020-04-20","time":"03:45:33","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"14. To summarize, I believe we must do all we can to control and contain the #SARSCoV2 coronavirus worldwide until we have a vaccine. \n\nBut if we fail to do this regionally, there are still actions that can save millions of lives. We need to thinking of these now, in time to act.","mentions":[],"urls":[],"photos":[],"replies_count":21,"retweets_count":49,"likes_count":278,"hashtags":["#sarscov2"],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1252080941377261568","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1252080370784202800,"conversation_id":"1252075528711860224","created_at":1587354197000,"date":"2020-04-20","time":"03:43:17","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"13. Of course there are many open questions here. How does the efficacy depend on the timing and duration of the shutdown? How bad it is to miss by a few days—or a few weeks—with the timing of the shutdown?","mentions":[],"urls":[],"photos":[],"replies_count":2,"retweets_count":11,"likes_count":128,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1252080370784202752","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1252080158837596200,"conversation_id":"1252075528711860224","created_at":1587354147000,"date":"2020-04-20","time":"03:42:27","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"12. One of the agonizing aspects of pandemic epidemiology is that one has to consider situations that seem intolerable and that should be avoided at any possible expense. \n\nYet should such a situation come to pass, it is good to know what one can do to ameliorate the harm.","mentions":[],"urls":[],"photos":[],"replies_count":3,"retweets_count":20,"likes_count":222,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1252080158837596162","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1252079760890421200,"conversation_id":"1252075528711860224","created_at":1587354052000,"date":"2020-04-20","time":"03:40:52","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"11. In my view, this is not a substitute for aggressive control and containment, because 60% of the population still becomes infected. In India, for example, this would cost about 19 million lives with a 2% infection fatality rate. \n\nBut the 30 day lockdown would save >5 million.","mentions":[],"urls":[],"photos":[],"replies_count":10,"retweets_count":29,"likes_count":199,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1252079760890421249","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1252078977671237600,"conversation_id":"1252075528711860224","created_at":1587353865000,"date":"2020-04-20","time":"03:37:45","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"10. This 30 day lockdown period is far less onerous than that required to hold the virus in check until a vaccine is available but reduces the total fraction infected from 90% to 70% by eliminating much of the overshoot.","mentions":[],"urls":[],"photos":[],"replies_count":1,"retweets_count":17,"likes_count":158,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1252078977671237632","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1252077342224089000,"conversation_id":"1252075528711860224","created_at":1587353475000,"date":"2020-04-20","time":"03:31:15","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"7. Reminder: I am not advocating this as a desirable control strategy. Where possible, I think the only option we have is to control the pandemic at low levels until a vaccine can be developed. \n\nStill, it is worth thinking about how to save lives if this goal cannot be attained.","mentions":[],"urls":[],"photos":[],"replies_count":3,"retweets_count":17,"likes_count":198,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1252077342224089088","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1252077341448126500,"conversation_id":"1252075528711860224","created_at":1587353475000,"date":"2020-04-20","time":"03:31:15","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"6. The key observation is that compared to controlling the pandemic well below the herd immunity threshold, reducing the number of cases due to overshoot may require shorter, less painful control measures.","mentions":[],"urls":[],"photos":[],"replies_count":1,"retweets_count":15,"likes_count":157,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1252077341448126464","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1252077340571521000,"conversation_id":"1252075528711860224","created_at":1587353475000,"date":"2020-04-20","time":"03:31:15","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"5. Of course there are major caveats to any of this theory: perhaps most importantly we don't yet know what fraction of recovered individuals develop protective immunity, nor how long this lasts. Herd immunity may not even be feasible. But even if it is....","mentions":[],"urls":[],"photos":[],"replies_count":3,"retweets_count":19,"likes_count":196,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1252077340571521025","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1252075531295547400,"conversation_id":"1252075528711860224","created_at":1587353043000,"date":"2020-04-20","time":"03:24:03","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"4. The basic point is that when an epidemic spreads through a population, herd immunity will be reached when a fraction 1-1/R0 of the population is infected—but the epidemic will keep going well past that point. These additional infections are known as overshoot.","mentions":[],"urls":[],"photos":[],"replies_count":4,"retweets_count":43,"likes_count":238,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1252075531295547395","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1252075529538175000,"conversation_id":"1252075528711860224","created_at":1587353043000,"date":"2020-04-20","time":"03:24:03","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"2. Some nations may simply lack the economic resources, technological capacity, and political will to contain the virus until a vaccine can be developed.\n\nShould this happen, I think it is important to consider how more modest control efforts could yield major benefits.","mentions":[],"urls":[],"photos":[],"replies_count":4,"retweets_count":46,"likes_count":377,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1252075529538174980","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1252075528711860200,"conversation_id":"1252075528711860224","created_at":1587353043000,"date":"2020-04-20","time":"03:24:03","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"1. I believe that if #SARSCoV2 is allowed to spread uncontrolled through an entire nation, it will be an unprecedented humanitarian disaster. Every possible measure should be taken to prevent this from happening. Yet in some countries this may be unavoidable.","mentions":[],"urls":[],"photos":[],"replies_count":53,"retweets_count":565,"likes_count":1616,"hashtags":["#sarscov2"],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1252075528711860224","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1252009788168269800,"conversation_id":"1251999295231819778","created_at":1587337369000,"date":"2020-04-19","time":"23:02:49","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"18. And that is the take-home point. Herd immunity without vaccination requires a huge number of infections, at least 1-1/R0. But in practice, you get far more people infected than that due to overshoot. \n\nThe cost in lives makes this approach untenable.","mentions":[],"urls":[],"photos":[],"replies_count":21,"retweets_count":150,"likes_count":481,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1252009788168269824","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1252008776770584600,"conversation_id":"1251999295231819778","created_at":1587337128000,"date":"2020-04-19","time":"22:58:48","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"16. Why is this happening? It takes place because an epidemic has something akin to momentum, in the form of people who are already infected when you reach the herd immunity threshold. An epidemic couldn't start anew from that place, but the current one can keep going.","mentions":[],"urls":[],"photos":[],"replies_count":4,"retweets_count":39,"likes_count":243,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1252008776770584577","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1252008621690347500,"conversation_id":"1251999295231819778","created_at":1587337091000,"date":"2020-04-19","time":"22:58:11","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"15. This overshoot represents a huge number of infections. For the model shown here, it represents nearly 30% of the population and nearly 33% of the total infections. So if letting the epidemic go through to herd immunity is even worse than it might sound.","mentions":[],"urls":[],"photos":[],"replies_count":2,"retweets_count":46,"likes_count":235,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1252008621690347520","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1252003866515628000,"conversation_id":"1251999295231819778","created_at":1587335957000,"date":"2020-04-19","time":"22:39:17","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"10. I can illustrate overshoot with a simple SEIR model of the COVID19 epidemic. These models have four types of individuals: susceptible, exposed, infectious, and recovered. \n(Researches use more complex models for forecasting. But this model allows us to understand the effect.)","mentions":[],"urls":[],"photos":[],"replies_count":2,"retweets_count":26,"likes_count":197,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1252003866515628032","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1252002993253183500,"conversation_id":"1251999295231819778","created_at":1587335749000,"date":"2020-04-19","time":"22:35:49","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"8. That's already untenably high. \n\nBut it's far worse. When an epidemic sweeps through, it won't stop once 1-1/R0 of the population have been infected. \n\nThis is because epidemics have momentum of a sort, and they overshoot the herd immunity threshold before coming to a halt.","mentions":[],"urls":[],"photos":[],"replies_count":8,"retweets_count":60,"likes_count":314,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1252002993253183488","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1252002731117564000,"conversation_id":"1251999295231819778","created_at":1587335686000,"date":"2020-04-19","time":"22:34:46","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"7. Assuming that immunity is complete and permanent—a huge assumption for #COVID19—herd immunity is reached once a fraction 1-1/R0 of the population has been infected. So if R0 is 2.5 for #SARSCoV2, herd immunity would require that 60% of the population become infected.","mentions":[],"urls":[],"photos":[],"replies_count":7,"retweets_count":55,"likes_count":286,"hashtags":["#covid19","#sarscov2"],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1252002731117563904","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1252002264387973000,"conversation_id":"1251999295231819778","created_at":1587335575000,"date":"2020-04-19","time":"22:32:55","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"6.  In an SIR or SEIR model, herd immunity is reached when the effective reproductive number Re drops below one, where Re=R0 * S and S is the fraction of the population that is susceptible to infection. Herd immunity thus arises when the fraction susceptible drops below S=1/R0.","mentions":[],"urls":[],"photos":[],"replies_count":3,"retweets_count":38,"likes_count":265,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1252002264387973120","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1252000974387900400,"conversation_id":"1251999295231819778","created_at":1587335268000,"date":"2020-04-19","time":"22:27:48","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"5. Herd immunity—while a disastrous control strategy for this pandemic—is a key concept in epidemiological modeling. This is the state at which enough people are immune that a new outbreak cannot take off—because a new case infects fewer than one downstream cases.","mentions":[],"urls":[],"photos":[],"replies_count":7,"retweets_count":57,"likes_count":305,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1252000974387900416","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1252000688239816700,"conversation_id":"1251999295231819778","created_at":1587335199000,"date":"2020-04-19","time":"22:26:39","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"4. The main point in the original thread was that if herd immunity requires 60% of the population to be infected, you can't just let the epidemic go unchecked and expect to suffer \"only\" 60% infected. This is because of something known as overshoot. Let's take a look.","mentions":[],"urls":[],"photos":[],"replies_count":13,"retweets_count":91,"likes_count":397,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1252000688239816704","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1252000265047175200,"conversation_id":"1251999295231819778","created_at":1587335098000,"date":"2020-04-19","time":"22:24:58","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"3. Given the uncertainties we face around the degree and duration of of acquired immunity, it is not even clear that one could reach herd immunity for #SARS2CoV. \n\nBut even if one could, the cost in lives would be unacceptable.","mentions":[],"urls":[],"photos":[],"replies_count":14,"retweets_count":200,"likes_count":622,"hashtags":["#sars2cov"],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1252000265047175168","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1251999634521682000,"conversation_id":"1251999295231819778","created_at":1587334948000,"date":"2020-04-19","time":"22:22:28","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"2. I think that it is important to talk about the science of epidemic models and how they work, so I am going to repost parts of the thread, but taking even more care to make it clear that allowing #COVID19 to go to herd immunity and beyond would be a disaster.","mentions":[],"urls":[],"photos":[],"replies_count":13,"retweets_count":145,"likes_count":549,"hashtags":["#covid19"],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1251999634521681920","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1251999295231819800,"conversation_id":"1251999295231819778","created_at":1587334867000,"date":"2020-04-19","time":"22:21:07","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"1. An hour ago I posted a thread explaining the concept of herd immunity and the problem of overshoot, whereby an epidemic infects more people that are required for herd immunity. \n\nDespite disclaimers, people interpreted it as an endorsement of the herd immunity approach.","mentions":[],"urls":[],"photos":[],"replies_count":96,"retweets_count":881,"likes_count":2044,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1251999295231819778","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1251346888399282200,"conversation_id":"1251344851984986118","created_at":1587179321000,"date":"2020-04-18","time":"03:08:41","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"Recruiting by Facebook seems to be a way to introduce strong selection biases. For weeks my email has been full of messages from people who think they had the disease in February or March and desperately want to get a serological test.","mentions":[],"urls":[],"photos":[],"replies_count":11,"retweets_count":8,"likes_count":119,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1251346888399282177","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1250984119556640800,"conversation_id":"1250984116020932609","created_at":1587092830000,"date":"2020-04-17","time":"03:07:10","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"6. But the key point is that we have to do more than watch the epidemic curves and wait for them to get low again. We have to figure out what we're going to do to keep them there, and that means finding ways to keep R0<1 while going to back to work and to our lives more broadly.","mentions":[],"urls":[],"photos":[],"replies_count":31,"retweets_count":91,"likes_count":512,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1250984119556640770","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1250984118860411000,"conversation_id":"1250984116020932609","created_at":1587092830000,"date":"2020-04-17","time":"03:07:10","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"5. The number of cases is not irrelevant, however. Knocking the number of cases down does bring new possibilities into play. For example, traditional shoe-leather epidemiology may work when there are a dozen cases in a city, but not when tens of thousands are infected at once.","mentions":[],"urls":[],"photos":[],"replies_count":3,"retweets_count":41,"likes_count":304,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1250984118860410882","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1250984118138990600,"conversation_id":"1250984116020932609","created_at":1587092830000,"date":"2020-04-17","time":"03:07:10","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"4. So it isn't really about \"When will cases be scarce enough that we can reopen the country?\" \n\nWhat we need to be asking is  \"Are we now able to do enough things differently than we did in February, so that we can to keep cases from increasing?\"","mentions":[],"urls":[],"photos":[],"replies_count":1,"retweets_count":139,"likes_count":546,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1250984118138990592","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1250984117413400600,"conversation_id":"1250984116020932609","created_at":1587092830000,"date":"2020-04-17","time":"03:07:10","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"3. Lifting social distancing isn't just a matter of driving the epidemic down to some target and then going back to life as before.\n\nIf we are going to lift social distancing, we have to do so in a way that keeps R0<1. Anything else and we'll too soon be back where we started.","mentions":[],"urls":[],"photos":[],"replies_count":16,"retweets_count":172,"likes_count":604,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1250984117413400578","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1250984116704575500,"conversation_id":"1250984116020932609","created_at":1587092830000,"date":"2020-04-17","time":"03:07:10","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"2. We are now entering a public conversation about when we can relax or even fully lift our social distancing measures. \n\nBut there's an absolutely key point that isn't getting enough focus in this discussion.","mentions":[],"urls":[],"photos":[],"replies_count":1,"retweets_count":31,"likes_count":246,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1250984116704575488","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1250984116020932600,"conversation_id":"1250984116020932609","created_at":1587092830000,"date":"2020-04-17","time":"03:07:10","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"1. Nationwide social distancing efforts appear to be working and new cases are declining nationwide. This is most welcome, b/c it easily could have been otherwise. Three weeks ago, it wasn't clear whether social distancing as practiced in a western democracy would be sufficient.","mentions":[],"urls":[],"photos":[],"replies_count":34,"retweets_count":272,"likes_count":1057,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1250984116020932609","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1250902650268213200,"conversation_id":"1250827416232062976","created_at":1587073407000,"date":"2020-04-16","time":"21:43:27","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"👆 \"we shouldn't\", not \"shouldn't we\"","mentions":[],"urls":[],"photos":[],"replies_count":5,"retweets_count":3,"likes_count":23,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1250902650268213248","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1250827417880391700,"conversation_id":"1250827416232062976","created_at":1587055470000,"date":"2020-04-16","time":"16:44:30","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"Whatever the origin of #SARSCoV2 may have been, going forward we need to carefully assess and manage the risk associated with a range of activities from wildlife markets to gain-of-function research to BSL4 labs in urban areas where spread would be rapid.","mentions":[],"urls":[],"photos":[],"replies_count":26,"retweets_count":136,"likes_count":728,"hashtags":["#sarscov2"],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1250827417880391680","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1250827417066692600,"conversation_id":"1250827416232062976","created_at":1587055470000,"date":"2020-04-16","time":"16:44:30","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"I don't think that lab escape is the most likely origin for the virus. Direct zoonotic origin seems far more plausible. And the evidence for lab escape has been circumstantial at best. But shouldn't we fall into the trap of dismissing it out of hand because of its source.","mentions":[],"urls":[],"photos":[],"replies_count":41,"retweets_count":132,"likes_count":818,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1250827417066692608","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1250827416232063000,"conversation_id":"1250827416232062976","created_at":1587055469000,"date":"2020-04-16","time":"16:44:29","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"There is strong evidence that the #SARSCoV2 #coronavirus is NOT an engineered bioweapon. \n\nThat said, it's important to be upfront that we do not have sufficient evidence to exclude entirely the possibility that it escaped from a research lab doing gain of function experiments.","mentions":[],"urls":[],"photos":[],"replies_count":128,"retweets_count":606,"likes_count":2074,"hashtags":["#sarscov2","#coronavirus"],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1250827416232062976","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1250671207147438000,"conversation_id":"1250654483320725504","created_at":1587018226000,"date":"2020-04-16","time":"06:23:46","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"OK so maybe you have to read the thread first. But a friend who rarely posts here just suggested, rather uncharitably, that when posting to twitter I have a faulty projection model that fails to account for the long tail of my thread length distribution. 🤣","mentions":[],"urls":[],"photos":[],"replies_count":5,"retweets_count":3,"likes_count":168,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1250671207147438081","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1250322762410758100,"conversation_id":"1250304069119275009","created_at":1586935151000,"date":"2020-04-15","time":"07:19:11","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"24. Some of the basic point of this thread would hold, namely that the back side of the death curve is forced into a functional form determined by the front side, without a free parameter to control their relative speeds. But the death curve would not be quite symmetric.","mentions":[],"urls":[],"photos":[],"replies_count":1,"retweets_count":7,"likes_count":108,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1250322762410758152","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1250322184964169700,"conversation_id":"1250304069119275009","created_at":1586935013000,"date":"2020-04-15","time":"07:16:53","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"23. If so, I'm wrong about the symmetry of the cumulative death function. The death curve would then be given by time derivative of e^D(t,⍺,β,ρ), which is not a symmetric function and instead has a slightly heavy right tail.","mentions":[],"urls":[],"photos":[],"replies_count":1,"retweets_count":8,"likes_count":102,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1250322184964169728","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1250304094582919200,"conversation_id":"1250304069119275009","created_at":1586930700000,"date":"2020-04-15","time":"06:05:00","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"20. As always, this thread represents my good faith effort to understand what is going on in this model. If I am mistaken about any of this, I welcome criticism and correction, and will update what I have here if necessary. \n\nThank you for reading and goodnight.","mentions":[],"urls":[],"photos":[],"replies_count":11,"retweets_count":7,"likes_count":256,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1250304094582919170","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1250304093693685800,"conversation_id":"1250304069119275009","created_at":1586930700000,"date":"2020-04-15","time":"06:05:00","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"19. Yet the IHME model forces symmetry between these phrases of the epidemic, simply because of the functional form they use to fit the data. We may see the model start to fail by large margins if this symmetry is not mirrored in the real world.","mentions":[],"urls":[],"photos":[],"replies_count":5,"retweets_count":32,"likes_count":189,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1250304093693685760","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1250304092708069400,"conversation_id":"1250304069119275009","created_at":1586930699000,"date":"2020-04-15","time":"06:04:59","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"18. The most important point is this: in practice, the death curves in US states result from two separate processes. A pre-controls expansion, and a post-controls contraction. I see no a priori reason why the contraction should occur at the same speed as the epidemic expansion.","mentions":[],"urls":[],"photos":[],"replies_count":1,"retweets_count":35,"likes_count":233,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1250304092708069379","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1250304091265192000,"conversation_id":"1250304069119275009","created_at":1586930699000,"date":"2020-04-15","time":"06:04:59","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"17. Wrapping up, let's look back at the death curve for the nation as a whole in post 1. It's not symmetric, even though the component curves are. This is unsurprising: the asymmetry largely arises from summing near-symmetric curves for each state w/ varying heights and timings.","mentions":[],"urls":[],"photos":[],"replies_count":2,"retweets_count":10,"likes_count":129,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1250304091265191939","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1250304090384371700,"conversation_id":"1250304069119275009","created_at":1586930699000,"date":"2020-04-15","time":"06:04:59","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"16. In defense of the model, every model is a tool with a purpose. The primary purpose of their model is to predict peak health care need, not the endpoint of the outbreak. That said, people need to be aware of a model's purpose and be cautious when using it for anything else.","mentions":[],"urls":[],"photos":[],"replies_count":10,"retweets_count":94,"likes_count":470,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1250304090384371713","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1250304089461682200,"conversation_id":"1250304069119275009","created_at":1586930699000,"date":"2020-04-15","time":"06:04:59","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"15. That depends on what R0 (R_e, strictly speaking—but they're about the same still) is in the population now. If R0 is just a shade under 1, the epidemic could stretch out for far longer. But the model cannot let that happen, because of its symmetry requirement.","mentions":[],"urls":[],"photos":[],"replies_count":5,"retweets_count":21,"likes_count":197,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1250304089461682178","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1250304087909781500,"conversation_id":"1250304069119275009","created_at":1586930698000,"date":"2020-04-15","time":"06:04:58","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"14. This strikes me as unrealistic. Even ignoring the real-world coupling between states (this is not included in the model), I am not persuaded that the epidemic will necessarily be entirely finished in just over a month.","mentions":[],"urls":[],"photos":[],"replies_count":6,"retweets_count":28,"likes_count":295,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1250304087909781504","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1250304082469740500,"conversation_id":"1250304069119275009","created_at":1586930697000,"date":"2020-04-15","time":"06:04:57","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"11. We've reached the peak in many states (hopefully). We've got the data for the up-slope of the death curve. But if I understand the IHME model correctly, it is now going to be forcing the down-slope, the back side of the curve, to be symmetric with the ramp up.","mentions":[],"urls":[],"photos":[],"replies_count":3,"retweets_count":17,"likes_count":140,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1250304082469740544","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1250304081265963000,"conversation_id":"1250304069119275009","created_at":1586930697000,"date":"2020-04-15","time":"06:04:57","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"10. In other words, the form of the curve that the researchers use to fit the data *forces* the predicted death curve to be symmetric. \n\nThis strikes me as being extremely important to understanding how the model is going to behave as we go forward.","mentions":[],"urls":[],"photos":[],"replies_count":4,"retweets_count":38,"likes_count":301,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1250304081265963010","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1250304077474304000,"conversation_id":"1250304069119275009","created_at":1586930696000,"date":"2020-04-15","time":"06:04:56","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"7. The answer is that this is a modeling assumption that the research team has made. They have chosen to fit a particular sigmoidal curve called the Gaussian Error Function (erf function, for short) to the data representing the cumulative number of deaths that have occurred.","mentions":[],"urls":[],"photos":[],"replies_count":2,"retweets_count":26,"likes_count":210,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1250304077474304001","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1250304076551581700,"conversation_id":"1250304069119275009","created_at":1586930696000,"date":"2020-04-15","time":"06:04:56","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"6. But this is a mix of two different processes, an acceleration phase prior to control, and a deceleration phase once controls are in place. \n\nGiven that, why does the model predict symmetric death curves?","mentions":[],"urls":[],"photos":[],"replies_count":1,"retweets_count":20,"likes_count":150,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1250304076551581699","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1250304075628818400,"conversation_id":"1250304069119275009","created_at":1586930695000,"date":"2020-04-15","time":"06:04:55","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"5. The basic story that the IHME model is laying out is a story in which we initially have an epidemic that is taking off. Then  control measures are put into place, and the epidemic is  brought under control with only about 3% of the population infected.","mentions":[],"urls":[],"photos":[],"replies_count":4,"retweets_count":15,"likes_count":120,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1250304075628818432","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1250206091218051000,"conversation_id":"1250204479284109312","created_at":1586907334000,"date":"2020-04-14","time":"23:35:34","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"^being *unable*.","mentions":[],"urls":[],"photos":[],"replies_count":1,"retweets_count":0,"likes_count":9,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1250206091218051074","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1250047443372134400,"conversation_id":"1250047443372134400","created_at":1586869509000,"date":"2020-04-14","time":"13:05:09","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"I’ll spare you from reading the comments on my recent dataviz thread. Summary:\n\nA: Hey check out my [misleading] graph that suggests [something false].\n\nB: That presentation is misleading because [reason].\n\nA: Oh yeah? Well my numbers are unreliable in the first place, so there!","mentions":[],"urls":[],"photos":[],"replies_count":10,"retweets_count":14,"likes_count":176,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1250047443372134400","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1249936247256039400,"conversation_id":"1249836446569181186","created_at":1586842998000,"date":"2020-04-14","time":"05:43:18","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"Followup: These data come from patients at New York-Presbyterian Allen in Inwood and Columbia University Irving in Washington Heights. Could the high prevalence here reflect health disparities in exposure risk across demographic groups, e.g. due to fraction continuing to work?","mentions":[],"urls":[],"photos":[],"replies_count":13,"retweets_count":8,"likes_count":94,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1249936247256039424","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1249930314580775000,"conversation_id":"1249930293928030209","created_at":1586841584000,"date":"2020-04-14","time":"05:19:44","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"16. In other words, it's OK to look at per-capita measures, but if you are plotting things on a linear scale, you need to make sure that the starting points are aligned in terms of their per-capita values. Anything else runs the risk of misleading your viewers.","mentions":[],"urls":[],"photos":[],"replies_count":4,"retweets_count":36,"likes_count":304,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1249930314580774913","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1249930311544090600,"conversation_id":"1249930293928030209","created_at":1586841583000,"date":"2020-04-14","time":"05:19:43","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"14. In this example the difference in epidemic trajectories is spurious. The regions and the country are increasing at the same rate—but different regions are doing it asynchronously. This asynchrony translates to a problematic comparison when graphing per-capita cases.","mentions":[],"urls":[],"photos":[],"replies_count":1,"retweets_count":17,"likes_count":161,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1249930311544090630","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1249930310424223700,"conversation_id":"1249930293928030209","created_at":1586841583000,"date":"2020-04-14","time":"05:19:43","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"13. While the difference in intercepts looks small because of due to the linear scaling on the y-axis, exponential growth quickly reveals the initial differences in starting heights.","mentions":[],"urls":[],"photos":[],"replies_count":1,"retweets_count":10,"likes_count":108,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1249930310424223744","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1249930309237260300,"conversation_id":"1249930293928030209","created_at":1586841582000,"date":"2020-04-14","time":"05:19:42","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"12.  At the time of the first case in the country, the per-capita prevalence for the country includes a set of disease-free regions. The y-intercept for the country is lower than the intercepts for each smaller region at the starts of their respective outbreaks.","mentions":[],"urls":[],"photos":[],"replies_count":1,"retweets_count":11,"likes_count":116,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1249930309237260294","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1249930304216678400,"conversation_id":"1249930293928030209","created_at":1586841581000,"date":"2020-04-14","time":"05:19:41","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"8. After further delays, dispersal initiates outbreaks in the purple and then orange regions as well. Within our four-region country, the number of cases is doubling every time step. Once an outbreak begins in any region, all else equal, it also increases approximately two-fold.","mentions":[],"urls":[],"photos":[],"replies_count":1,"retweets_count":11,"likes_count":102,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1249930304216678400","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1249930301351948300,"conversation_id":"1249930293928030209","created_at":1586841581000,"date":"2020-04-14","time":"05:19:41","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"6. Why might per capita cases (infected individuals or fatalities) in a large country such as the U.S. appear to be increasing slower than per capita cases in smaller countries, even when there is no difference in the actual rate of increase?","mentions":[],"urls":[],"photos":[],"replies_count":1,"retweets_count":14,"likes_count":120,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1249930301351948288","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1249930299258990600,"conversation_id":"1249930293928030209","created_at":1586841580000,"date":"2020-04-14","time":"05:19:40","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"4. So which is right? Should you divide by population size, or not? I think you can—but you need to start each country from a constant *fraction* of cases, not a constant number of cases. Then you can see prevalence data, but you are not mislead by comparisons between countries.","mentions":[],"urls":[],"photos":[],"replies_count":7,"retweets_count":52,"likes_count":382,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1249930299258990592","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1249930293928030200,"conversation_id":"1249930293928030209","created_at":1586841579000,"date":"2020-04-14","time":"05:19:39","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"1. When plotting epidemic curves or death totals, should we divide by population size? Here on twitter this question has generated a lot more heat than light. \n\nThe answer is a bit subtle and so while I’ve tweeted about this before I want to address it in more detail.","mentions":[],"urls":[],"photos":[],"replies_count":54,"retweets_count":823,"likes_count":1957,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1249930293928030209","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1249892984918687700,"conversation_id":"1249836446569181186","created_at":1586832684000,"date":"2020-04-14","time":"02:51:24","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"Near parturition during a pandemic, expectant mothers might be particularly cautious about health. Untested symptomatics would be rare in that particular subpopulation. If so the ratio of a-/presymptomatic patients to symptomatic in this sample could be far lower than in gen pop.","mentions":[],"urls":[],"photos":[],"replies_count":12,"retweets_count":7,"likes_count":85,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1249892984918687747","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1249892504549253000,"conversation_id":"1249836446569181186","created_at":1586832569000,"date":"2020-04-14","time":"02:49:29","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"Lots of discussion of what this means regarding the fraction of asymptomatic or pre-symptomatic cases. It's a bit difficult to tell without knowing exactly what route #COVID19 women near parturition would take through the hospital system.","mentions":[],"urls":[],"photos":[],"replies_count":1,"retweets_count":5,"likes_count":78,"hashtags":["#covid19"],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1249892504549253120","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1249856476572569600,"conversation_id":"1249856078994497537","created_at":1586823979000,"date":"2020-04-14","time":"00:26:19","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"Here's the thing. These people are doing science. In science, it's not hypocrisy to change your mind based on new evidence. It's literally the entire purpose of the enterprise. \n\nMuch of what we believed a month ago we still believe. Some of it we don't. That's how science works.","mentions":[],"urls":[],"photos":[],"replies_count":103,"retweets_count":1233,"likes_count":4112,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1249856476572569600","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1249856079749451800,"conversation_id":"1249856078994497537","created_at":1586823885000,"date":"2020-04-14","time":"00:24:45","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"Then someone jumps in and accuses them of hypocrisy or incompetence. \"You just said probably X, but two weeks ago you said probably not X. You're a fraud, just like all of you experts!\"","mentions":[],"urls":[],"photos":[],"replies_count":4,"retweets_count":83,"likes_count":604,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1249856079749451776","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1249856078994497500,"conversation_id":"1249856078994497537","created_at":1586823885000,"date":"2020-04-14","time":"00:24:45","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"We're far enough into this pandemic that I'm seeing something interesting happen. Epidemiologists start talking about a new result, such as the NEJM paper on a high rate of asymptomatic positives presenting for delivery in NYC, and discussing what that means.","mentions":[],"urls":[],"photos":[],"replies_count":27,"retweets_count":247,"likes_count":982,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1249856078994497537","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1249837438026920000,"conversation_id":"1249836446569181186","created_at":1586819440000,"date":"2020-04-13","time":"23:10:40","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"People are asking why I am surprised by these numbers. I would have guessed a far lower than one-in-six prevalence in NYC.","mentions":[],"urls":[],"photos":[],"replies_count":37,"retweets_count":12,"likes_count":220,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1249837438026919936","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
{"id":1249492540346085400,"conversation_id":"1249480343968575488","created_at":1586737210000,"date":"2020-04-13","time":"00:20:10","timezone":"UTC","user_id":3238448948,"username":"ct_bergstrom","name":"Carl T. Bergstrom","place":"","tweet":"Now it sure looks like the 1,000,000 person population in yellow, the one is handling the epidemic better. It's not. It has the same number of cases on every day as the other population does. \n\nThis is what people are doing when they use the graph above to claim US is doing well.","mentions":[],"urls":[],"photos":[],"replies_count":7,"retweets_count":69,"likes_count":433,"hashtags":[],"cashtags":[],"link":"https://twitter.com/CT_Bergstrom/status/1249492540346085376","retweet":false,"quote_url":"","video":0,"near":"","geo":"","source":"","user_rt_id":"","user_rt":"","retweet_id":"","reply_to":[{"user_id":"3238448948","username":"CT_Bergstrom"}],"retweet_date":"","translate":"","trans_src":"","trans_dest":""}
