It is set to be a two-tailed test which refers to the difference between the mean distances. Here, refers to the mean driving distance of the new golf ball whilst refers to the mean driving distance of the current golf ball. When the difference between the mean distances is equal to 0, therefore, the null hypothesis rejected. This shows that the new golf ball is better.
With the formula, the value of the test statistics was computed. This is a necessary step to find the p-value. Next step would be computing the degree of freedom using the formula as such: . The findings presented a test statistics of and the degree of freedom of 76. Therefore, the p-value is greater than the level of significance which was chosen to be 0.05 and the null hypothesis is not rejected. It is recommended for Par Inc. to produce new golf balls with the coating as to increase their market share.
Current
New
Mean
270.275
267.5
Variance
76.61474291
97.94871868
Standard Deviation
8.7529848
9.8969045
Standard Error
1.383968415
1.564838
Using the formula, the interval estimation was calculated. Therefore, with confidence at 95% the differences between the mean distances are in between -1.385740214 and 6.935740214 yard.
The sample size is said to have an inverse relationship with standard error: as the sample size increases, the