Answer Happy

11. To examine the effects of physical exercise on academic performance twenty students were randomly assigned to one of two conditions. The control condition was kept as sedentary as possible. They were asked to sit as much as possible and walk slowly if they had to go somewhere. The exercise group was asked to minimize sitting and stand as much as possible, run when they had to go somewhere, and overall try to be as active as possible. After two weeks they were all given the same exam in a nuclear physics class. The scores obtained from the students are shown below. Sedentary Group 70 80 77 77 79 73 75 79 4 85 76 74 81 Active Group 89 86 88 89 85 94 91 90 95 96 a) Calculate descriptive statistics (mean, standard deviation) for each group and create a table.(1 pts) b) Create a bar graph showing the mean and standard deviation for each group. (1 pts) c) Calculate the standard deviation of the combined sample (equation pg 213)(2) d) Calculate the effect size. (formula pg 213) (2 pts) e) Calculate a confidence interval for the difference between the means (equations pg 213)(2 pts) (use the N₁-N₂ formula for the standard error of the difference)(2 pts) f) Conduct a t-test to see if there is a significant difference between the means (formula pg 220)(2 pts) g) Write a brief sentence explaining the results of this study. Did being active have any impact on their exam scores? (2 pts)