In: Statistics and Probability
Professional Golfers’ Earnings Two random samples of earnings of professional golfers were selected. One sample was taken from the Professional Golfers Association, and the other was taken from the Ladies Professional Golfers Association. At a=0.10, is there a difference in the means? The data are in thousands of dollars. Use the critical value method with tables.
PGA 1147, 1344, 9188, 5687, 10508, 4910, 8553, 7573, 375
LPGA. 48, 76, 863, 100, 1876, 2029, 4364
Assume the variables are normally distributed and the variances are unequal.
Part 2 of 5 Find the critical value(s). Round the answer(s) to at least three decimal places. If there is more than one critical value, separate them with commas. Critical value(s):
Solution:
The given data is as follows:
PGA | LPGA |
1147 | 48 |
1344 | 76 |
9188 | 863 |
5687 | 100 |
10508 | 1876 |
4910 | 2029 |
8553 | 4364 |
7573 | |
375 |
I have used excel to solve this problem.
Step 1: Let 1 be the sample mean for PGA and 2 be the sample mean for LPGA.
The hypothesis for the test are given as follows:
H0:1 =2
H1:1 2
The appropriate test is two-sample independent t-test.
Step 2:Let us follow these steps in excel to find the result.
The output from the excel is as below:
t-Test: Two-Sample Assuming Unequal Variances | ||
Variable 1 | Variable 2 | |
Mean | 5476.11111 | 1336.571 |
Variance | 14395506.1 | 2489767 |
Observations | 9 | 7 |
Hypothesized Mean Difference | 0 | |
df | 11 | |
t Stat | 2.96045522 | |
P(T<=t) one-tail | 0.00648237 | |
t Critical one-tail | 1.36343032 | |
P(T<=t) two-tail | 0.01296473 | |
t Critical two-tail | 1.79588482 |
From theabove table t-stat=2.96 which isgreater than t-critical=1.79. So we reject null hypothesis and conclude that there is difference im means.