Bookmark and Share

Notice: On April 23, 2014, Statalist moved from an email list to a forum, based at

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: st: Troubleshooting comparison of means across groups

From   Richard Goldstein <>
Subject   Re: st: Troubleshooting comparison of means across groups
Date   Thu, 28 Jun 2012 10:19:28 -0400

yes, look at the help file and you will see that you need a comma before
the "by"


On 6/28/12 10:12 AM, Kerry MacQuarrie wrote:
> Hi all,
> I am trying to run t tests to compare means of some (continuous) variables
> across groups.  However, I'm running in to some puzzling error messages.
> If I run the code ttest varname by(groupvar), I get: "factor variables and
> time-series operators not allowed".  Any ideas on where to start looking to
> troubleshoot this?
> Thanks for any suggestions.
> Kerry
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> Kerry MacQuarrie
> NSF Fellow and CSDE Trainee
> Sociology Department
> University of Washington
*   For searches and help try:

© Copyright 1996–2017 StataCorp LLC   |   Terms of use   |   Privacy   |   Contact us   |   Site index