To perform hypothesis testing.
Answer to Problem 46E
There is convincing evidence that there is an association between age and online banking for internet users.
Explanation of Solution
Given:
Age | |||||
18-29 | 30-49 | 50-64 | 65+ | ||
Online banking | Yes | 265 | 352 | 304 | 167 |
No | 130 | 190 | 249 | 189 |
The null and alternative hypotheses:
Using excel,
18-29 | 30-49 | 50-64 | 65+ | Total | ||
Yes | Observed | 265 | 352 | 304 | 167 | 1088 |
Expected | 232.81 | 319.45 | 325.93 | 209.82 | 1088.00 | |
(O - E)² / E | 4.45 | 3.32 | 1.48 | 8.74 | 17.98 | |
No | Observed | 130 | 190 | 249 | 189 | 758 |
Expected | 162.19 | 222.55 | 227.07 | 146.18 | 758.00 | |
(O - E)² / E | 6.39 | 4.76 | 2.12 | 12.54 | 25.81 | |
Total | Observed | 395 | 542 | 553 | 356 | 1846 |
Expected | 395.00 | 542.00 | 553.00 | 356.00 | 1846.00 | |
(O - E)² / E | 10.84 | 8.08 | 3.59 | 21.28 | 43.80 | |
43.80 | chi-square | |||||
3 | Df | |||||
1.67E-09 | p-value |
Chi-square test statistic = 43.80. The degrees of freedom = 3 and p-value = 0.
Decision: P-value < 0.05, reject H0.
Conclusion: There is convincing evidence that there is an association between age andonline banking.
Chapter 11 Solutions
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