Question

# In a study of the effect of college student employment on academic performance, the following summary...

In a study of the effect of college student employment on academic performance, the following summary statistics for GPA were reported for a sample of students who worked and for a sample of students who did not work. The samples were selected at random from working and nonworking students at a university. (Use a statistical computer package to calculate the P-value. Use ?employed ? ?not employed. Round your test statistic to two decimal places, your df down to the nearest whole number, and your P-value to three decimal places.)

 Sample Size Mean GPA Standard Deviation Students Who Are Employed 176 3.22 0.485 Students Who Are Not Employed 118 3.33 0.514
 t = df = P =

Does this information support the hypothesis that for students at this university, those who are not employed have a higher mean GPA than those who are employed? Use a significance level of 0.05.

Yes OR No?

H0:

H1:

t = ()/sqrt(s1^2/n1 + s2^2/n2)

= (3.22 - 3.33)/sqrt((0.485)^2/176 + (0.514)^2/118)

= -1.84

df = (s1^2/n1 + s2^2/n2)^2/((s1^2/n1)^2/(n1 - 1) + (s2^2/n2)^2/(n2 - 1))

= ((0.485)^2/176 + (0.514)^2/118)^2/(((0.485)^2/176)^2/175 + ((0.514)^2/118)^2/117)

= 241

P-value = P(T < -1.84)

= 0.0335

As the P-value is less than the significance level (0.0335 < 0.05), we should reject the null hypothesis.

Yes, this information support the hypothesis that for students at this university, those who are not employed have a higher mean GPA than those who are employed.

#### Earn Coins

Coins can be redeemed for fabulous gifts.