3. The national mean score of an aptitude test is 50 with a standard deviation of...

3. The national mean score of an aptitude test is 50 with a standard deviation of 5. I think students at Ohio University can earn higher scores than people nationally. I survey 30 students at Ohio University and find a mean 57 with a standard deviation of 6.8. Is the mean scores of Ohio University students significantly more than the mean score of the aptitude test nationally? (use  = .05)

a. State the null and alternative hypotheses in symbols. (2 points)

b. Set up the criteria for making a decision. That is, find the critical value(s). (1 point)

c. Compute the appropriate test statistic. Show your work. (3 points)

d. Based on your answers above, evaluate the null hypothesis. (1 point) Reject Fail to reject (circle one)

e. State your conclusion in words. (1 point)

f. Given your decision, what type of error could have been committed? (1 point) Type I error Type II error (circle one)

Solutions

Expert Solution

n >= 30

so we use z-test

type 1 error could've been committed if the null hypothesis was actually true

(please UPVOTE)

orchestra answered 1 year ago

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