---
title: "design_sigma_type"
output: md_document
---

# Standard deviations

When assuming the outcomes are normally distributed, __multiarm__ requires values to be specified for the standard deviations, $\sigma_0,\dots,\sigma_K$, of the responses accrued in the control arm and each of the experimental arms.
For a single-stage design, the options are that they are equal across all arms, equal across the experimental arms, or unequal across all arms.
Specify your chosen assumption about the standard deviations here.
For a multi-stage design, the options are that they are equal across all arms or equal across the experimental arms.
Specify your chosen assumption about the standard deviations here.
Depending on your choice, suitable input boxes will then appear for you to specify the actual values of the standard deviations.
