In: Statistics and Probability
In the book Business Research Methods (5th ed.), Donald R. Cooper and C. William Emory discuss a market researcher for an automaker who is studying consumer preferences for styling features of larger sedans. Buyers, who were classified as “first-time” buyers or “repeat” buyers, were asked to express their preference for one of two types of styling—European styling or Japanese styling. Of 40 first-time buyers, 7 preferred European styling and 33 preferred Japanese styling. Of 60 repeat buyers, 42 preferred European styling, and 18 preferred Japanese styling.
(a) Set up a contingency table for these data.
Style | |||
Buyers | European | Japanese | Total |
First-time | |||
Repeat | |||
Total | __ans6__ | ||
(b) Test the hypothesis that buyer status (repeat versus first-time) and styling preference are independent at the .05 level of significance. What do you conclude? (Round your answer to 3 decimal places.)
χ2χ2 = |
(a)
Contingency Table for these data is calculated as follows:
European | Japanese | Total | |
First - time | 7 | 33 | 40 |
Repeat | 42 | 18 | 60 |
Total | 49 | 51 | 100 |
(b)
Expected Frequency Table for these data is calculated as follows:
European | Japanese | Total | |
First - time | 49X40/100=19.60 | 51X40/100=20.40 | 40 |
Repeat | 49X60/100=29.40 | 51X60/100=30.60 | 60 |
Total | 49 | 51 | 100 |
Test Statistic is calculated as follows:
Observed Frequency (O) | Expected Frequency (E) | (O - E)2/E |
7 | 19.60 | 8.100 |
33 | 20.40 | 7.782 |
42 | 29.40 | 5.400 |
18 | 30.60 | 5.188 |
Total = = | 26.47 |
Test Statistic = 26.470
ndf = (r-1) X (c - 1)
= (2 - 1) X (2 - 1)
= 1
By Technology, p - value < 0.00001
Since p - value is less than = 0.05,the difference is significant. Reject null hypothesis.
Correct option:
Reject H0: independence