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Paired Samples T-test Independent Samples T-test Multiple Regression One Way Analysis of Variance


Independent Samples T-Test (continued)

This will bring you to a table containing 12 components. For this example, we will use the means for the Phoneme Deletion task (PD).

We will now go through each component, filling in the appropriate number using the data in this study.

1. Test significance level, a
Alpha is the probability of rejecting the null hypothesis of equal means when it is true (the probability of a Type I error).

Suggestion: Enter 0.05, a frequent standard

Acceptable entries: 0.001 to 0.20

**For this example: Shankweiler et al. set a = .05. So type ".05" in the first box.

2. One-sided or two-sided test
A two-sided (two-tailed) test will reject the null hypothesis if differences are large and positive or large and negative. A one-sided (one-tailed) test rejects the null hypothesis only for differences in a single direction (positive or negative).

Suggestion: Enter 2, a frequent standard

Acceptable entries: 1 or 2

**For this example: Shankweiler et al. designed this as a one-tailed test. So type "1" in the second box.