Purpose:  The purpose of these four programs is to display the critical values from the chi-squared, f-, t- and z-distributions.  The critical values are given for a variety of alpha…
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Purpose:  The purpose of this program is to illustrate how the power changes as the mean for the alternative hypothesis changes.  This is done by graphing the distributions for the…
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Purpose:  The purpose of this program is to show curves representing the distribution of the null and alternative hypotheses and illustrating the rejection region and the area representing power.  The…
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Purpose:  The regpt command is a teaching tool for showing the influence of one point in a regression analysis, allowing you to see how the point influences the regression line,…
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Purpose:  The purpose of this program is to facilitate the comparison between a standard normal distribution and the sampling distribution of the mean for the sample size specified by the…
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Purpose:  The purpose of this program is to allow a comparison between a univariate t-test and a multivariate t-squared test.  The program creates a dataset with two variables, X and…
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Purpose:  The purpose of this program is to display a t-distribution and a standard normal distribution for the number of degrees of freedom specified by the user.  Download:  You can download…
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Purpose:  The purpose of this program is to calculate z-scores for either sample (i.e., single) observations or for sample means.  In each case the formula is displayed. Download:  You can…
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Purpose:  The purpose of this program is to display a z-distribution with vertical lines drawn at up to four z-values.  Download:  You can download this program from within Stata by typing…
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Purpose:  The purpose of this program is to display two normal distributions with vertical lines drawn at their means.  Download:  You can download this program from within Stata by typing search…
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