# Statistics

Assume alpha 0.05 2-tailed where not mentioned)

2. A doctor is interested in whether or not the amount of time a child eats breast milk has a relationship with eventual memory scores. The following data (located at the bottom of the page) on 8-year-old children has been collected. Determine if there is a relationship and what type is may be. a. The value of the appropriate statistic equals _________. b. The proportion of variability of Y a ccounted for by X is _________.

3. A distribution has a mean of 150.00 and a standard deviation of 8.3. (12 points)

a. The raw score corresponding to a z score of 0.00 is _________

b. The z score for a raw score of 123 is ______________

c. The z score for a raw score of 168 is ______________

4. A resent study researched the possible impact meditation on depression. (The chart is located at the bottom of the page). A total of 10 subjects were ran through a baseline and then, after 4 months of meditation training, a second measure of their depression scores were taken. Use the most powerful test you were taught in order to analyze this repeated measures design. (alpha 0.05) a. What is the Alternative hypothesis? b. State the Null hypothesis. c. What is obtained value for the appropriate test utilized, the critical value it is compared to, and your conclusion?

5. A marketing group is interested in which of 3 soft-drink formulas to market in Paris, as the French do not care for the same taste in pop as Americans do. Three groups are selected at random to rate each of the 3 formulas. (The chart is located below). What conclusions can you make from the ratings: (alpha 0.05)

a. State the alternative hypothesis.

b. state the null hypothesis

Complete the table. What can you conclude (remember to include your critical value

7. Suppose a statistics instructor is interested in assessing whether there is a significant difference in the mean achievement scores of Math 101 students who are taught under two conditions. The first condition is a highly structured environment in which a fixed time is given for the teaching and learning of Math concepts. The second condition is a less structured environment in which the same concepts are presented but with no set time for completion of the teaching-learning process. An achievement test given at the end of six weeks to the 17 participants in the study who were randomly assigned to one of the two conditions gives the following results: (alpha 0.05)(See chart below) (12 points) a. What is the Alternative hypothesis? b. State the Null hypothesis. c. What is obtained value for the appropriate test utilized, the critical value it is compared to, and your conclusion?

8. The MPAA says that piracy has drastically decreased the profit of most movies. A researcher tracks 24 months worth of movie profits and finds the average is $3.7 million with a standard deviation of $0.6 million. The studio claim is that the average monthly profit on movies is $4.9 million. Does the data support the MPAA’s claim?

a. What is the Alternative hypothesis?

b. State the Null hypothesis.

c. What is obtained value for the appropriate test utilized, the critical value it is compared to, and your conclusion?

9. Imagine that you have been hired by the Jelly Belly Company to run the sorting machine, which contains 200 jelly beans. One hundred are red, 40 are green, 30 are yellow, 25 are white, and 5 are black. If you reached into the machine without looking and grabbed a jelly bean, what is the probability that it is: (12 points)

a. Green?

b. Black?

c. Not yellow?

d. Red or white?

e. Green, yellow, or black?

Now imagine that you are to select two jelly beans, however, you must put the first jelly bean back before you make your second selection (with replacement). What is the probability that you will select a:

f. Red jelly bean on the first selection and a black jelly bean on the second selection?

g. Green and yellow?

h. Yellow, yellow, and yellow?

The President of the company says this procedure is gross, so she allows you to select two jelly beans without putting the first one back (without replacement). What is the probability that you will select a:

i. White and black?

j. Red and green?