In: Statistics and Probability
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.
1. The statistics final exam score for a population of college students in a major metropolitan university is 64 with a standard deviation of 5. One of the instructors decides to use a new teaching method to help with retention of material across all courses. To test the new teaching method, the department randomly selects 25 students from the population and records a mean statistics final exam score of 68. Conduct a directional hypothesis test to determine whether the new teaching method has an effect on retention of course material.