In an analysis of variance, which value is determined by the size of the sample variances? a. SSbetween b. SSwithin c. dfbetween d. dfwithi

Researchers want to know if a tutoring program affects students’ ACT scores. They used a sample of twenty students and tested them before and after the tutoring program. Use Excel to perform a dependent sample t-test to determine whether the difference between the mean pretest score and the mean posttest score is significantly different. Assume unequal variance.   Subject Pretest Posttest 1 21 25 2 30 33 3 25 26 4 28 31 5 31 34 6 16 16 7 19 21 8 21 24 9 26 27 10 34 34 11 22 23 12 18 24 13 14 17 14 19 23 15 24 25 16 33 30 17 25 27 18 26 26 19 22 24 20 19 18

Question: A company conducted a survey to gather data on the ages of its employees. The collected data are as follows: 25, 28, 30, 35, 38, 40, 42, 45, 48, 50. Calculate the range, variance, and standard deviation of the ages.

We are interested in determining whether or not the variances of the sales at two music stores (A and B) are equal. A sample of 16 days of sales at store A has a sample variance of 20 while a sample of 26 days of sales from store B has a sample variance of 30. The test statistic is