Multiple Choice
Identify the
letter of the choice that best completes the statement or answers the question.


1.

A
Type II error is committed when a.  a true alternative hypothesis is mistakenly
rejected  b.  a true null hypothesis is mistakenly
rejected  c.  the sample size has been too small  d.  not enough
information has been available   


2.

The
level of significance in hypothesis testing is the probability of a.  accepting a true
null hypothesis  b.  accepting a false null hypothesis  c.  rejecting a true
null hypothesis  d.  None of these alternatives is
correct.   


3.

In
hypothesis testing if the null hypothesis has been rejected when the alternative hypothesis has been
true, a.  a Type I error
has been committed  b.  a Type II error has been committed  c.  either a Type I
or Type II error has been committed  d.  the correct decision has been made   


4.

The
probability of making a Type I error is denoted by


5.

Which
of the following does not need to be known in order to compute the pvalue? a.  knowledge of
whether the test is onetailed or twotailed  b.  the value of the
test statistic  c.  the level of significance  d.  None of these
alternatives is correct.   


6.

A
student believes that the average grade on the final examination in statistics is at least 85. She
plans on taking a sample to test her belief. The correct set of hypotheses is a.  H_{0}:
m <
85 H_{a}:
m ³
85  b.  H_{0}:
m £
85 H_{a}:
m >
85  c.  H_{0}:
m ³
85 H_{a}:
m <
85  d.  H_{0}:
m >
85 H_{a}:
m £
85   



Exhibit 97
A random sample of 16 statistics examinations from a
large population was taken. The average score in the sample was 78.6 with a variance of 64. We are
interested in determining whether the average grade of the population is significantly more than 75.
Assume the distribution of the population of grades is normal.


7.

Refer
to Exhibit 97. At 95% confidence, it can be concluded that the average grade of the
population a.  is not
significantly greater than 75  b.  is significantly greater than 75  c.  is not
significantly greater than 78.6  d.  is significantly greater than 78.6   



Exhibit 94
The manager of a grocery store has taken a random
sample of 100 customers. The average length of time it took the customers in the sample to check out
was 3.1 minutes with a standard deviation of 0.5 minutes. We want to test to determine whether or not
the mean waiting time of all customers is significantly more than 3 minutes.


8.

Refer
to Exhibit 94. The standardized test statistic is a.  1.96  b.  1.64  c.  2.00  d.  0.056   


9.

Refer
to Exhibit 94. The pvalue is a.  0.025  b.  0.0456  c.  0.05  d.  0.0228   


10.

Refer
to Exhibit 94. At 95% confidence, it can be concluded that the mean of the population
is a.  significantly
greater than 3  b.  not significantly greater than 3  c.  significantly
less than 3  d.  significantly greater then 3.18   
