527 / 762
Chapter 12: Hypothesis Tests – Large Samples
527
√
= (10 - 120
0.05)/2.3875 = 1.6754.
: For a significance level of
= 0.01, reject the null hypothesis if the
computed test statistic value
= 1.6754 < -
= -2.33.
Conclusion:
Since
= 1.6754 > -
= -2.33, then the null hypothesis
will not be rejected. There is insufficient sample evidence to confirm your
professor’s claim. That is, there is insufficient sample evidence to claim that
less than 5% of the student population on your campus is left handed, at the
1% level of significance.
Note:
This means that there is not a significant difference between the
sample proportion of 10/130 = 0.0833 and the postulated proportion of 0.05.
Figure 12-5
displays the test statistic in relation to the rejection region.
Observe that the test statistic falls in the do not reject region.