1. What information, specifically, does a z-score provide (e.g., suppose someone has a z-

score of -0.50, what does that mean)? (4 pts)

2. Use formulae and narrative descriptors to describe what is meant by the Central Limit

Theorem AND explain how the Central Limit Theorem formalizes the notion that larger

samples generally provide more accurate inferential information about a population mean

than smaller samples (8 pts).

3. In statistical hypothesis testing, why is it necessary to use a "null hypothesis"? (4 pts)

4. With regard to an experimenter's decision about the null hypothesis, DESCRIBE the two

correct decisions AND the two errors which can be made (12 pts).

5. In statistical hypothesis testing, specifically what does "p is less than .05" mean (4 pts)

6. Identify how each of the following affects the power of a statistical test (4 pts):

a. using 30 subjects rather than 20 subjects

b. decreasing the magnitude of a treatment effect

COMPUTATIONAL PROBLEMS. ALL WORK MUST BE SHOWN FOR FULL

CREDIT

7. Hershey's makes approximately 60 million kisses a day. The average weight of a Hershey's

kiss is m = 4.54 grams (with s = .07). What is the probability of opening a bag of kisses and

finding a kiss somewhere between 4.50 and 4.60 grams?

8. Have you ever counted how many Cheerios are in a box of Cheerios? In a 12 oz. box, there are

approximately 2750. Suppose that the numbers form a normal distribution with a mean of 2750

and a standard deviation of 175. Finding a box that had 3150 Cheerios would be kind of unusual,

I guess. Suppose that the average weight of a tomato is 5.5 ounces (with a standard deviation of

1.0 oz). How big would a tomato have to be, to be as weird as a box of cereal with 3150 Cheerios

in it. (Wow...talk about aardvarks and airplanes!). Step 1. Don't panic; Step 2. Draw the curve.

Step 3. Answer question

9. Dr. Mark Etting works for an advertising agency in New York City. He develops a new ad

campaign for a craft beer company which involves the use of a celebrity spokesperson. Suppose

that before the celebrity spokesperson ad, average beer sales were $24.51 thousand per month

(with s = $2.60 thousand per month). For the SIX months after the celebrity advertising

campaign was started, average monthly beer sales was $26.10. Use the 5-step hypothesis-testing

procedure to assess whether the new advertising campaign was effective in significantly

increasing beer sales? (you may use the numbers as they are presented; i.e., use 24.51 rather than

24,510)