---
title: "design_ratio_type"
output: md_document
---

# Allocation ratios

__multiarm__ requires values to be specified for the target (stage-wise amongst the remaining treatment arms, in the case of multi-stage designs) allocation ratios, $r_1,\dots,r_K$, of the number of patients to assign to experimental arms $1,\dots,K$ relative to the control arm.
For a single-stage design, the options are that they are equal across all arms, equal across the experimental arms, unequal across all arms, based on the $\sqrt{K}$-rule ($r_1=\dots,r_K=1/\sqrt{K}$), or chosen for $A$-, $D$-, or
$E$-optimality.
For a multi-stage design, the options are that they are equal across all arms, equal across the experimental arms, or based on the $\sqrt{K}$-rule ($r_1=\dots,r_K=1/\sqrt{K}$).
Specify your chosen type of allocation ratios here.
Depending on your choice, suitable input boxes may then appear for you to specify the actual values of the allocation ratios.
