Activity 2: California Bar Exam

The State Bar of California is considering changing its exam structure such that instead of 200 multiple-choice questions, there will be 180. Before making any changes permanent, they first want to collect data to compare the outcomes of the two structures. They have obtained a representative sample of 85 Law students and randomly assigned each to take either the new or old exam. The summarized sample data is given in the table below.

Exam	N	Mean	SD
New	42	65.9	5.9
Old	43	63.6	3.2

Activity 2_A:

Construct a 95% confidence interval to estimate the mean difference in the bar exam scores of the two groups. Use Minitab; you should not need hand calculations.

Remember to upload all relevant Minitab output and to identify your answers.

Activity 2_B:

Use the five-step hypothesis testing procedure given below to determine if there is evidence that the mean bar scores are different in the population at the 0.05 alpha level. If assumptions are met, conduct a t-test. Use Minitab; you should not need hand calculations.

Remember to upload all relevant Minitab output and to identify your answers.

Activity 2_B:

Step 1: Check assumptions and write hypotheses.

Activity 2_B:

Step 2: Calculate the test statistic.

Activity 2_B:

Step 3: Determine the p value.

Activity 2_B:

Step 4: Decide to reject or fail to reject the null.

Activity 2_B:

Step 5: State a "real world" conclusion.

Activity 2_B:

Compute Cohen's d for the difference in the two sample means. You will need to do calculations by hand. Remember to show all work.

Activity 2_B:

Interpret the value of Cohen's d that you computed in the previous question.