Question

Directions: For each question, you need to show each step of the hypothesis test, state your null and alternate hypothesis, identify if you are conducting a two-tailed or a one-tailed hypothesis test, identify the Zcrit and Zobt, graph the normal curve, label the critical value and the test statistic, shade the rejection region, tell whether we reject or retain the null and make a conclusion statement. You also need to calculate Cohen’s d, the probability of committing a type I error and type II error, and the strength of the effect size.

3. A common measure of assessing whether individuals are suitable for entrance into law school is by having applicants register and take the Law School admissions Test (LSAT). The national average score on the LSAT is 150 with a standard deviation of 6. A Law School Admissions coordinator at a local university created a prep course to assist local students in preparing for the exam. To test whether this new prep course had an effect on LSAT scores for students she drew a random sample of students who had taken the LSAT with a total sample size of 15 and a mean of 153. Use a directional one-sample z test to determine whether the new prep course has an effect on LSAT scores.

Answer 1

cohen's d = |Xbar- mu|/sigma = | 153 -150)|/6 = 0.5