vtest

F-test for the ratio of two groups' variances. This is similar to var.test except using the summarized input.

This is a core implementation of 'SAS' procedures for linear models - GLM, REG, ANOVA, TTEST, FREQ, and UNIVARIATE. Some R packages provide type II and type III SS. However, the results of nested and complex designs are often different from those of 'SAS.' Different results does not necessarily mean incorrectness. However, many wants the same results to SAS. This package aims to achieve that.
Reference: Littell RC, Stroup WW, Freund RJ (2002, ISBN:0-471-22174-0).

Kyun-Seop Bae

sasLM

'SAS' Linear Model

vtest function

<dl> <dt>v1</dt>
<dd>sample variance of the first (test, active, experimental) group</dd> <dt>n1</dt>
<dd>sample size of the first group</dd> <dt>v0</dt>
<dd>sample variance of the second (reference, control, placebo) group</dd> <dt>n0</dt>
<dd>sample size of the second group</dd> <dt>ratio</dt>
<dd>value for the ratio of variances under null hypothesis</dd> <dt>conf.level</dt>
<dd>confidence level</dd></dl>

Arguments

Author

F-Test for the ratio of two groups' variances — vtest

<dl>

 <dt>v1</dt>
<dd>sample variance of the first (test, active, experimental) group</dd>

 <dt>n1</dt>
<dd>sample size of the first group</dd>

 <dt>v0</dt>
<dd>sample variance of the second (reference, control, placebo) group</dd>

 <dt>n0</dt>
<dd>sample size of the second group</dd>

 <dt>ratio</dt>
<dd>value for the ratio of variances under null hypothesis</dd>

 <dt>conf.level</dt>
<dd>confidence level</dd>

</dl>

vtest: F-Test for the ratio of two groups' variances

Description

Usage

Value

Arguments

Author

Details

Examples