WEEK 8 SELF-TEST QUESTIONS WITH VALID
SOLUTIONS
True or False: An ANOVA compares three or more independent sample averages. -
✔✔True
Suppose you believe that there is a statistical difference between the test scores of juniors
and seniors in a high school economics class. The null hypothesis (H0) is that the mean
scores of juniors (μj) is = to the mean scores of seniors (μs) (also noted as H0: μj = μs).
What is the alternative hypothesis (Ha)? - ✔✔Ha: μj ≠ μs - alternative hypothesis is exact
opposite of the null
Which of the following is a valid null hypothesis?
a) P > 1/8.
b) The mean of population A is not equal to the mean of sample A
c) Mu = 100
d) none of the above - ✔✔ c) Mu = 100, a null often states that there is no difference
between b/w two sets of data
True or False: It is a best practice to state the null hypothesis before running the
hypothesis test in QI Macros. - ✔✔True
True or False: It is appropriate to determine if the test is one- or two- tailed after running
a hypothesis test in QI Macros. - ✔✔False
If the calculated power is 80%, the beta risk is ____________. - ✔✔Beta risk = 20%
Significance level is also referred to as _______.
a) beta risk
b) p
c) confidence sigma
, d) alpha risk - ✔✔d) alpha risk (type I error)
A teacher suspects that the mean test scores of males are different from the mean test
scores of females. The best type of hypothesis test in this situation would be
___________________. - ✔✔two-sample t-test
True or False: A two-tailed test describes a hypothesis test that is concerned with one side
of the frequency distribution. - ✔✔False, concerned with both sides
True or False: Alpha risk is also referred to as a Type I error. - ✔✔True
True or False: Alpha risk is also referred to as a Type II error. - ✔✔False, beta risk =
type II error
The ___________ is the exact opposite of the null hypothesis and contains all of the other
possibilities. - ✔✔Alternative hypothesis
In hypothesis testing, which of the following statements is always true?
a) The P-value is greater than the significance level.
b) The P-value is computed from the significance level.
c) The P-value is the parameter in the null hypothesis.
d) The P-value is a test statistic.
e) The P-value is a probability. - ✔✔e) The P-value is a probability.
True or False: You want to prove that the setting does not make a difference. Therefore,
you want to reject the null hypothesis. - ✔✔False,
True or False: It is appropriate to determine if the test is one- or two- tailed prior to
running a hypothesis test in QI Macros. - ✔✔True
SOLUTIONS
True or False: An ANOVA compares three or more independent sample averages. -
✔✔True
Suppose you believe that there is a statistical difference between the test scores of juniors
and seniors in a high school economics class. The null hypothesis (H0) is that the mean
scores of juniors (μj) is = to the mean scores of seniors (μs) (also noted as H0: μj = μs).
What is the alternative hypothesis (Ha)? - ✔✔Ha: μj ≠ μs - alternative hypothesis is exact
opposite of the null
Which of the following is a valid null hypothesis?
a) P > 1/8.
b) The mean of population A is not equal to the mean of sample A
c) Mu = 100
d) none of the above - ✔✔ c) Mu = 100, a null often states that there is no difference
between b/w two sets of data
True or False: It is a best practice to state the null hypothesis before running the
hypothesis test in QI Macros. - ✔✔True
True or False: It is appropriate to determine if the test is one- or two- tailed after running
a hypothesis test in QI Macros. - ✔✔False
If the calculated power is 80%, the beta risk is ____________. - ✔✔Beta risk = 20%
Significance level is also referred to as _______.
a) beta risk
b) p
c) confidence sigma
, d) alpha risk - ✔✔d) alpha risk (type I error)
A teacher suspects that the mean test scores of males are different from the mean test
scores of females. The best type of hypothesis test in this situation would be
___________________. - ✔✔two-sample t-test
True or False: A two-tailed test describes a hypothesis test that is concerned with one side
of the frequency distribution. - ✔✔False, concerned with both sides
True or False: Alpha risk is also referred to as a Type I error. - ✔✔True
True or False: Alpha risk is also referred to as a Type II error. - ✔✔False, beta risk =
type II error
The ___________ is the exact opposite of the null hypothesis and contains all of the other
possibilities. - ✔✔Alternative hypothesis
In hypothesis testing, which of the following statements is always true?
a) The P-value is greater than the significance level.
b) The P-value is computed from the significance level.
c) The P-value is the parameter in the null hypothesis.
d) The P-value is a test statistic.
e) The P-value is a probability. - ✔✔e) The P-value is a probability.
True or False: You want to prove that the setting does not make a difference. Therefore,
you want to reject the null hypothesis. - ✔✔False,
True or False: It is appropriate to determine if the test is one- or two- tailed prior to
running a hypothesis test in QI Macros. - ✔✔True
