### Statistics-hypothesis questions

Assignment Help Basic Statistics
##### Reference no: EM13110503

1. A researcher claims that the average age of people who buy lottery tickets is 70. A sample of 30 is selected and their ages are recorded as shown below. The standard deviation is 16. At alpha = 0.05 is there enough evidence to reject the researcher's claim?

49 63 90 52 22 80 72 56 82 56

24 46 70 74 70 61 65 71 39 74

79 76 71 49 62 68 71 67 69 45

2. Choose a variable (such as number of daily admissions at a local theater or number of miles students have to commute daily to get to their college.) Before collecting the data, decide what a likely average might be, then complete the following:

Scenario: Number of customers at a late night fast food restaurant.

Variable: 30

Likely Average: 15

a. Write a brief statement of purpose of the study

b. Define the population

c. State the hypotheses for the study

d. Select an a value

e. State how the sample was selected

f. Show the raw data

g. Compute the test statistic

h. Find the critical values(s)

i. State the decision

j. Summarize the results

You may obtain raw data from the random number table in the appendix section of your text or from any other sources on the World Wide Web.

3. List the steps involved in hypothesis testing using: a) the traditional/classical method; b) the probability-value method. Provide an example of each.

4. A sample size of 35 is used to test H0: m 65 vs. Ha: < 65.

Given that = 63.5 and = 2.5, answer the following questions

a. What is the computed value of the test statistic?

b. What distribution does the test statistic have when the null hypothesis is true?

c. Is the alternative hypothesis one-tailed or two-tailed?

d. What is the p-value?

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