In: Statistics and Probability
Suppose that a recent issue of a magazine reported that the
average weekly earnings for workers who have not received a high
school diploma is $498. Suppose you would like to determine if the
average weekly for workers who have received a high school diploma
is significantly greater than average weekly earnings for workers
who have not received a high school diploma. Data providing the
weekly pay for a sample of 50 workers are available in the file
named WeeklyHSGradPay. These data are consistent with the findings
reported in the article.
Weekly Pay
687.73 543.15 789.45
442.26 684.85 661.43
478.3 629.62 486.95
786.47
652.15 652.82 669.81
641.13 577.24 845.68
541.59 553.36 743.25
468.61
821.71 757.82 657.34
506.95 744.93 553.2
827.92 663.85 685.9
637.25
530.54 515.85 588.77
506.62 720.84 503.01
583.18 7,980.24 465.55
593.12
605.33 701.56 491.86
763.4 711.19 631.73
605.89 828.37 477.81
703.06
(a)
State the hypotheses that should be used to test whether the mean
weekly pay for workers who have received a high school diploma is
significantly greater than the mean weekly pay for workers who have
not received a high school diploma. (Enter != for ≠ as
needed.)
H0:
Ha:
(b)
Use the data in the file named WeeklyHSGradPay to compute the
sample mean, the test statistic, and the p-value. (Round your
sample mean to two decimal places, your test statistic to three
decimal places, and your p-value to four decimal places.)
sample mean =
778.01
test statistic =
1.927
p-value =
0.0299
(c)
Use
α = 0.05.
What is your conclusion?
Reject H0. We can not conclude that the mean weekly pay for workers
who have received a high school diploma is higher than that for
workers who have not received a high school diploma.
Reject H0. We can conclude that the mean weekly pay for workers who
have received a high school diploma is higher than that for workers
who have not received a high school diploma.
Do not reject H0. We can not conclude that the mean weekly pay for
workers who have received a high school diploma is higher than that
for workers who have not received a high school diploma.
Do not reject H0. We can conclude that the mean weekly pay for
workers who have received a high school diploma is higher than that
for workers who have not received a high school diploma.
(d)
Repeat the hypothesis test using the critical value approach.
State the null and alternative hypotheses. (Enter != for ≠ as
needed.)
H0:
Ha:
Find the value of the test statistic. (Round your answer to three
decimal places.)
State the critical values for the rejection rule. (Round your
answers to three decimal places. If the test is one-tailed, enter
NONE for the unused tail.)
test statistic ≤
test statistic ≥
State your conclusion.
Reject H0. We can not conclude that the mean weekly pay for workers
who have received a high school diploma is higher than that for
workers who have not received a high school diploma.
Reject H0. We can conclude that the mean weekly pay for workers who
have received a high school diploma is higher than that for workers
who have not received a high school diploma.
Do not reject H0. We can not conclude that the mean weekly pay for
workers who have received a high school diploma is higher than that
for workers who have not received a high school diploma.
Do not reject H0. We can conclude that the mean weekly pay for
workers who have received a high school diploma is higher than that
for workers who have not received a high school diploma.