Question

An instructor believes that students do not retain as much information from a lecture on a Friday compared to a Monday. To test this belief, the instructor teaches a small sample of college students some preselected material from a single topic on statistics on a Friday and on a Monday. All students received a test on the material. The differences in exam scores for material taught on Friday minus Monday are listed in the following table. Difference Scores (Mon-Fri) 3.4, 6.2, 1.0, 4.5, -1.6 (a) Find the confidence limits at a 95% CI for these related samples.

Answer 1

difference score <- c(3.4,6.2,1.0,4.5,-1.6) > n <- length (di fference score) > n [1] 5 > t table <- qt (0.975 , n-1) t table [1] 2.776445 > mean <- mean (difference score) > mean [1] 2.7 > standarddeviation <- sd(difference_score) > standard deviation [1] 3.056141 > #95% confidence interval for difference score is > lower_bound <mean-t_table* (standard_deviation/sqrt (n)) > lower bound [1] -1.094701 > upper bound <mean+t_table* (standard_deviation/sqrt (n)) upper bound [1] 6.494701