1. If the confidence coefficient is 0.9, ________.
we expect that 9 samples out of 100 will support the null hypothesis
we expect that 90 out of 100 samples will support the null hypothesis
we expect that 10 samples out of 100 will support the null hypothesis
we expect that all 100 samples will support the null hypothesis
2. Use the information below to answer the question.
The following table provides data on a sample of customers who visited a local restaurant. The restaurant owner believes that the average profit per customer exceeds $25.
36.73 35.50
25.92 38.36
41.65 25.50
18.78 19.78
33.14 22.22
20.85 26.23
22.13 32.33
28.46 34.15
34.72 24.21
24.20 28.95
21.84 19.74
20.75
Which of the following is the correct conclusion?
The null hypothesis that the average profit per customer exceeds $25 cannot be rejected.
The null hypothesis that the average profit per customer does not exceed $25 is rejected.
The null hypothesis that the average profit per customer does not exceed $25 cannot be rejected.
The null hypothesis that the average profit per customer exceeds $25 is rejected.
3. Hypothesis testing is a technique that allows you to draw statistically valid conclusions about ________.
random errors
sample statistics
population parameters
individuals
4. Another term for p-value is ________.
degrees of freedom
random effect
probability density function
observed significance level
5. The null hypothesis ________.
describes an existing theory or belief that is accepted as correct in the presence of contradictory data
describes an existing theory or belief that is accepted as correct in the absence of contradictory data
is based on new information provided by sample data
is based on new information provided by population data
6. The power of the test represents the ________.
probability of correctly failing to reject the null hypothesis when it is indeed true
probability of incorrectly rejecting the null hypothesis when it is actually true
probability of incorrectly failing to reject the null hypothesis when it is actually false
probability of correctly rejecting the null hypothesis when it is indeed false
7. When conducting two-sample tests for means with independent samples, ________.
it is always assumed that the population variances are equal
the test for equality of variances is conducted, and if the variances are not equal the t-test in Excel should not be used
the test for equality of variances is conducted to determine if the variances are equal and thereby choose the appropriate t-test in Excel
it is always assumed that the population variances are unequal
8. The t-Test Statistic has a t distribution with ________ degrees of freedom.
n
n + 1
n - 2
n - 1
9. Use the below information to answer the question.
A company wishes to test whether the proportion of female managers is the same as the proportion of male managers. The following table provides data for a sample of employees.
Females Males
Number of managers 18 23
Sample size 45 75
Which of the following is the conclusion?
We reject H0 that the proportion of female managers is the same as the proportion of male managers.
We should not reject H0 that the proportion of female managers is not the same as the proportion of male managers.
We reject H0 that the proportion of female managers is not the same as the proportion of male managers.
We should not reject H0 that the proportion of female managers is the same as the proportion of male managers.
10. Use the information below to answer the question.
The following table provides data on a sample of customers who visited a local restaurant. The restaurant owner believes that the average profit per customer exceeds $25.
36.73 35.50
25.92 38.36
41.65 25.50
18.78 19.78
33.14 22.22
20.85 26.23
22.13 32.33
28.46 34.15
34.72 24.21
24.20 28.95
21.84 19.74
20.75
Formulate the null and the alternative hypotheses to determine if the data supports the restaurant owner's claim.
H0: The average profit per customer = $25
H1: The average profit per customer ? $25
H0: The average profit per customer = $25
H1: The average profit per customer > $25
H0: The average profit per customer = $25
H1: The average profit per customer < $25
H0: The average profit per customer > $25
H1: The average profit per customer = $25
11. In statistical terminology, educational level is an example of a ________.
continuous variable
residual
factor
dependent variable
12. To assess the effect of an intervention such as the productivity of an employee before and after a training class, one would conduct a(n) ________.
independent samples t-test
ANOVA
paired samples t-test
F-test
13. Hypothesis testing involves drawing inferences about two contrasting ________ relating to the value of a population parameter.
theorems
data sets
assumptions
propositions
14. An online retailer wanted to see if purchasing patterns were different between male consumers and female consumers. Males were found to have spent a mean of $85 per month on online purchases, whereas females were found to have spent a mean of $78 per month. An independent samples t-test was conducted to assess the observed difference between the two groups of consumers. A two-tailed test was applied. The value of the t-Test Statistic for the observed differences was -4.7, where the p-value is less than 0.0002. What conclusion can be made about the observed difference?
There is a statistically significant difference between the two groups of consumers.
There is statistically no significant difference between the two groups of consumers.
The independent samples t-test is not the appropriate hypothesis-testing procedure.
There is not sufficient information to conclude.
15. Use the below information to answer the following question.
A company wishes to test whether the proportion of female managers is the same as the proportion of male managers. The following table provides data for a sample of employees.
Females Males
Number of managers 18 23
Sample size 45 75
Formulate the null and the alternative hypotheses to determine if the proportion of female managers is the same as the proportion of male managers.
H0: pfemales - pmales ≠ 0
H1: pfemales - pmales = 0
H0: pfemales - pmales = 0
H1: pfemales - pmales > 0
H0: pfemales - pmales = 0
H1: pfemales - pmales ≠ 0
H0: pfemales - pmales = 0
H1: pfemales - pmales < 0
16. Two-tailed tests ________.
have only lower critical values
have only upper critical values
have both upper and lower critical values
do not have any critical values
17. Statistical inference is the process of drawing conclusions about ________ from sample data.
surveys
populations
individuals
sampling errors
18. The alternative hypothesis ________.
___________ describes an existing theory or belief that is accepted as correct in the absence of contradictory data.
is based on new information provided by population data.
is based on new information provided by sample data.
is not deemed to be an important part of inferential statistics.
19.
Use the information below to answer the question.
The following table provides data on a sample of customers who visited a local restaurant. The restaurant owner believes that the average profit per customer exceeds $25.
36.73 35.50
25.92 38.36
41.65 25.50
18.78 19.78
33.14 22.22
20.85 26.23
22.13 32.33
28.46 34.15
34.72 24.21
24.20 28.95
21.84 19.74
20.75
Which of the following is the test statistic?
1.717
-1.867
1.867
-1.826
20. The power of the test depends on ________.
the true value of the population mean
the level of confidence used
the sample size
all of the above