In: Statistics and Probability
You have obtained the number of years of education from one random sample of 35 police officers from City A and the number of years of education from a second random sample of 30 police officers from City B. The average years of education for the sample from City A is 15 years with a standard deviation of 2 years. The average years of education for the sample from City B is 14 years with a standard deviation of 2.2 years. Is there a statistically significant difference between the education levels of police officers in City A and City B? What is the appropriate test for this case? 2 sample z-test Chi-square test 2 sample paired t-test 2-sample t-test
Carry out the test. The test statistic =
and the p-value is =
There sufficient evidence at the 5% level to conclude that the education levels of police officers in City A and City B is significantly different.
(a)
Question:
What is the appropriate test for this case?
2-sample t-test
(b)
Question:
Carry out the test.
H0: Null Hypothesis: ( The education levels of police officers in City A and City B is not significantly different.)
HA: Alternative Hypothesis: ( The education levels of police officers in City A and City B is significantly different.) (Claim)
n1 = 35
1 = 15
s1 = 2
n2 = 30
2 = 14
s2 = 2.2
Pooled Standard Deviation is given by:
Test Statistic is given by:
So,
(i)
The test statistic = 1.919
(ii)
ndf = 35 + 30 -2 =63
By Technology, P Value = 0.0595
So,
the p-value is = 0.0595
(iii)
Since P - value = 0.0595 is greater than = 0.05, the difference is not significant. Fail to reject null hypothesis.
Correct option:
There is not sufficient evidence at the 5% level to conclude that the education levels of police officers in City A and City B is significantly different.