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help for ttesttable
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 Differences in means by groups including the T-test


        ttesttable outcome groupvar [if] [in] [, unequal tex(str)
                 pretable(str) posttable(str) force]



Description

    ttesttable is a very simple Stata module that performs a
    mean-comparison test (t-Test) for all possible combinations of groups
    defined by a variable. For instance, if you have 4 types of
    observations and you would like to see if there are differences in
    means between groups, this module computes the t-test for all six
    possible combinations. The output is presented in a table of
    differences in means and includes the significance level of the t-test.
    This table can be exported directly as a LaTeX file and the underlying
    matrices are available for further use in Stata.

    outcome This variable must be numeric and contains the variable you
    would like to test.

    groupvar This variable must be a categorical variable with either
    numerical values or strings.


Options

    unequal This option corresponds to the unequal option of the command
    ttest, meaning that no equal variances of the outcome variable are
    assumed for the two groups.

    tex(str) Use this option to export the displayed table directly to
    latex. Specify the name of the file (without the file extension). The
    table will be generated with the LaTeX tabular environment. To include
    the table environment, use the options pretable(str) and posttable(str)

    pretable(str) Include here LaTeX code you would like to have in the
    tex-file before the tabular environment. This option is only available
    when the option tex(str) is specified.

    posttable(str) Include here LaTeX code you would like to have in the
    tex-file after the tabular environment. This option is only available
    when the option tex(str) is specified.

    force By default, the program stops working when more than
    10 categories are detected, since this will lead to
    extremely large tables and is most likely due to the use of
    a continuous variable as grouping variable. If you want to
    perform the analysis with more than the generally admitted
    10 categories, use the option force, which elimiates this
    limit.

Output
    Besides the screen output and the export to LaTeX,
    ttesttable generates three matrices which can be accessed
    through "return list":

        r(p) : matrix of p-values

        r(t) : matrix of t statistics

        r(diff) : matrix of differences in means


Example

    ttesttable score country, tex(myfile)
    pre("\begin{table}[!ht]\centering") post("\caption{Cross
    table of differences in mean by group\end{table}"

    This example will provide a matrix containing the
    differences in the average scores across countries and
    performs a T-test for any combination of groups. The stars
    will indicate if the difference is significantly different
    from zero. The table will be exported to the file myfile.tex
    and include the table environment as defined by the options
    pre() and post()

Author

    For suggestions and questions, please contact the author:
    Florian Chávez Juárez: florian@chavezjuarez.com