Question

This is from chapters of making sense of statistics 7th edition. End of chapter questions. There is no data. These are general questions.

1. In a dependent Samples t test what is the df for a sample of 100 participants in a particular study?
2. The dependent samples t test would have less sampling error in its design. Discuss the reasons.
3. Given the results below what would you conclude about the mean difference between Group A and Group B.
4. Give an example of one continuous data and one categorical data with two categories that would require performing a dependent sample t Test

Answer 1

The df for dependent sample t test is n-1= 100-1 = 99

The dependent sample t test has less sampling error because Paired t-test compares study subjects at 2 different times (paired observations of the same subject). Unpaired t-test (aka Student’s test) compares two different subjects. The paired t-test reduces intersubject variability (because it makes comparisons between the same subject), and thus is theoretically more powerful than the unpaired t-test.

Example for dependent sample t test with continuous data

For categorical data , the dependent sample test is conducted using McNrmar test . Example for this is