Question

9.8 Test for one variance (Optional)

The variance in the number of employees needed daily in a certain pharmacy has been 4. After the pharmacy changed its general manager, the variance is thought to have changed. To test it, a sample of the number of employees required per day for 15 days. Do a hypothesis test (two tailed) for the variance is with a confidence of 80%

1. State the hypothesis.
2. Find the left critical value (Use chi square table)
3. Find right critical value (Use Chi square table).
4. If your sample data is (9, 9, 9, 10, 13, 8, 12, 11, 10, 14, 9, 13, 7, 11, 13) calculate the value of the statistic.
5. Find the probability of Type I error.
6. State your decision (We reject or accept the null hypothesis)
   Ps: i think n = 60. 15 days multiplied by 4.

Answer 1

1) H0: variance the number of employees needed daily in a certain pharmacy is 4.

H1 : variance in the number of employees needed daily in a certain pharmacy is not 4.

2) left critical value = 7.79

Right critical value = 21.064

3) test Statistics = 7.35

4) Decision - variance in the number of employees needed daily in a certain pharmacy is not 4. PL?☺️