Question

14.2 The manager of the Houston Astros decides to see whether batting practice has any impact on the Astros’ hitting. Twenty Astros take batting practice; they are randomly selected. Ten Astros, randomly selected, take no batting practice (the control group). After 25 games, the figures shown in the accompanying table are available. What can you tell the manager about his experiment, statistically and managerially?

	Batting Practice Group	No-Practice Group
Mean	.212	.193
Standard deviation	.026	.047

Answer 1

let sample 1 = Batting Practice Group

sample 2 = No-Practice Group

using minnitab>stat>basic stat>two sample t

we have

Two-Sample T-Test and CI

Sample N Mean StDev SE Mean
1 20 0.2120 0.0260 0.0058
2 10 0.1930 0.0470 0.015

Difference = μ (1) - μ (2)
Estimate for difference: 0.0190
95% CI for difference: (-0.0081, 0.0461)
T-Test of difference = 0 (vs ≠): T-Value = 1.43 P-Value = 0.162 DF = 28
Both use Pooled StDev = 0.0342

since p value is large so we ca say that there is o significat differece between the batting practice ad o batting bpractice group  on the Astros’ hitting.