how you should interpret a decision that rejects

1. how you should interpret a decision that rejects the null hypothesis. Explain how you would interpret a decision that fails to reject the null hypothesis.

a. It is reported that the number of residents in Wisconsin who support plans to recall the governor is 48%.

b. An Amish bakery store states that the average shelf life of their fresh baked goods is seven days.

c. A soda manufacturer states that the average number of calories in the regular soda is less than 150 calories per serving.

2. The census figures show that the average income for a family in a rural region is approximately $34,860 per year. A random sample has a mean income of $33,566 per year, with a standard deviation of $1,245. At a sig. level of .0.01 is there enough evidence to reject the claim? Explain.

3. An advertising firm claims that the average expenditure for advertising for their customers is at least $12,500 per year. You want to test this claim, so you randomly select 10 of their customers. The results are listed below. At a sig. level of .01 can you reject this claim? Explain.

13,445 11,220 10,157 13,217 9,990

12,125 10,116 14,350 13,590 12,100

4. Find the critical value(s) for the indicated test for a population variance, sample size, and sig. level.

a. Right-tailed test – Sample Size (25), Significance (.05)

b. Two-tailed test – Sample Size (11), Significance (.01)

c. Two-tailed test – Sample size (66), Significance (.10)

d. Left-tailed test – Sample Size (18), Significance (.05)

5. The employees in a grocery store are handing out samples of a certain brand of Pizza. This is the pizza company’s way of determining whether people like the brand of pizza and would prefer it over other brands. Do you think this type of sampling is representative of the population? Explain. Identify possible flaws or biases in this study.

6. Classify the following as independent or dependent and explain your answer.

a. Sample 1 – The males in the class

Sample 2 – The females in the class

b. Sample 1 – Blood Pressure of fifteen people in a nursing home

c. Sample 2 – Blood pressure of the same fifteen people one week later

7. A researcher claims that taking a protein supplement as part of a weight gainer program for athletes will help them gain muscle weight. The weights in pounds of 10 athletes are listed below before and after using the protein supplement. At a sig. of .05 can you conclude that this supplement helps the athletes gain weight?

Athlete

1

2

3

4

5

6

7

8

9

10

Weight Before

196

220

187

184

206

198

174

176

182

174

Weight After

198

224

185

185

213

196

178

180

175

174

8. Technology:A math teacher claims that the average final exam scores for the seventh grade boys and girls are equal. The average score for 10 randomly selected boys is 87 with a standard deviation of 11. The average score for 10 randomly selected girls is 89 with a standard deviation of 12. State the null and alternate hypotheses. At a sig. of .05 can you reject the teacher’s claim? Assume normal distribution and equal variances. Please use Excel for your calculations. What is your analysis?

9. Application: Create a small data set based on something you are interested in. You will need to form a null and alternate hypothesis and perform a one-sample test based on the sample. Discuss your analysis based on the output. If you are unsure of ideas for a data set, you can look online or in your text for ideas. However, do not copy word-for-word.