STAT177 homework sheet #7

A museum conducted a survey of 200 of its members and 200 of the general public telling them about new upcoming exhibits. After telling a respondent about the exhibits, they asked how likely it would be for the person to visit the museum within the following 12 months. These were the results:

	Member	Non-member	Total
Likely to visit	144	115	259
Not likely	56	85	141
Total	200	200	400

1) What is the appropriate test? (Z test)

2) Are members more likely to visit new exhibits than non-members? Test at 5%. (p-value = 0.001)

3) Is there a level of significance between 1% and 10% that could have been chosen in which the opposite verdict could have been reached? (no since the p-value is less than 0.01)

4) A deli with 3 checkout counters took 100 sales from each counter and classified them as shown in the following crosstab:

	Counter A	Counter B	Counter C	Total
Under $30	48	35	27	110
$30 to under $40	34	38	35	107
$40 and over	18	27	38	83
Total	100	100	100	300

Based on organizing the data this way, do the sales depend on the counter? Test at 5%. To what degree does the amount of the sale depend on the counter? (p-value = 0.009; conclude the amount of the sale depends on the counter; degree of dependence = 15.07%)

5) Create a histogram showing the sales breakdown for each counter. Why is it not necessary to first compute the percentage of sales for each counter? (Each counter has an equal number of sales)

From the text, read:

Chapter 5, pages 93-98 (to end of section on Z test for 2 proportions)

Chapter 6, pages 115-118 (to end of section on test for independence)