Question

2. A company institutes an exercise break for its workers to see if it will affee satisfaction, as measured by a questionnaire that assesses workers' satisfactio for 10 randomly selected workers before and after the implementation of the program are shown in the table below. exercise Before 34 28 29 45 26 27 24 1515 27 After 33 36 50 41 3741 39 121 20 37 Do these results provide evidence that workers' satisfaction has changed? Assume the conditions allow the use of paired-t procedures. State appropriate hypotheses Perform the test conclusion indicating the value of the test statistic and the P-value. State your Create a 95% confidence interval for the mean difference in job satisfaction due to the exercise break.

Answer 1

2:

Hypotheses are:

$H_{0}:\mu_{d}=0,H_{a}:\mu_{d}\neq 0$

Following is the output of t test generated by excel:

Hypothesis Test: Paired Observations 0.000 hypothesized value 27.000 mean Before 35.500 mean After -8.500 mean difference (Before - After) 7.472 std. dev. 2.363 std. error 10 n 9 df 3.60 t 0058 p-value (two-tailed) -13.845 confidence interval 95% lower 3.155 confidence interval 95.% upper 5.345 margin of error

The test statistics is

t = -3.60

The p-value is

p-value = 0.0058

Since p-value is less than 0.05 so we reject the null hypothesis. That is there is evidence that worker's satisfaction has been changed.

The 95% confidence interval is: ( -13.845, -3.155).