Data Analysis Toolpak

Using the Data Analysis Tool

As an example, examine the use of the ToolPak for completing a t test between two paired samples of observations, pre- and post-intervention. In Figure 1, you see the scores for the 10 cases' data in column A (the Pre condition) and the scores for the same 10 cases in column B (the Post condition). Finally, you can also see the t-Test: Paired Two Sample for Means dialog box output of the Data Analysis ToolPak showing the following:

Figure 1 Using the Data Analysis ToolPak for Analyzing Dependent Means

• Mean and Variance—the means and variances for each group
• Observations—the number of observations
• Pearson Correlation—the Pearson correlation coefficient
• The Hypothesized Mean Difference
• df—the degrees of freedom (df) associated with the t value
• t Stat—the t statistic
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• P(T<=t) one-tail—the probability that a value of t would be different from chance for a one-tailed test
• t Critical one-tail – the critical value for rejection of the null hypothesis for a one-tailed test
• P(T<=t) two-tail—the probability that a value of t would be different from chance for a two-tailed test
• t Critical two-tail—The critical value for rejection of the null hypothesis for a two-tailed test