Researchers hypothesized that young adults would report a re

Researchers hypothesized that young adults would report a reduction in consumption of doughnuts after attending a psycho-educational intervention during which there is a discussion of a suspected link between the use of sugar, stress, and depression. Researchers selected a sample of 30 students and measured the number of doughnuts they ate in the week before the class and the number of doughnuts the same group ate in the week after the class.

What is the critical value used to test the null hypothesis (3 decimal places)?

Solution

This test is a related samples t test.

The degrees of freedom is n-1=30-1=29.

Let the significance level alpha=0.05.

Thus the one tail critical value is t(29,0.05)=1.699