STAT 211 EXAM 2 QUESTIONS AND 100%
CORRECT ANSWERS!!
In hypothesis testing if the null hypothesis is rejected, _____.
A. the alternative hypothesis must also be rejected
B. the evidence supports the alternative hypothesis
C. no conclusions can be drawn from the test
D. the data must have been collected incorrectly
B
In the hypothesis testing procedure, α (alpha) is
A.
the level of significance
B.
1 - level of significance
C.
the critical value
D.
the confidence level
a
If Ho is not rejected at a 5% level of significance, it _____. (Hint: Draw the picture and
think about it.)
A. will also not be rejected at the 1% level
B. will always be rejected at the 1% level
C. will sometimes be rejected at the 1% level
a
f a hypothesis test has a Type I error probability of .05, that means if the null hypothesis is
_____.
A. true, it will be rejected 5% of the time
B. true, it will not be rejected 5% of the time
,C. false, it will not be rejected 5% of the time
D. false, it will be rejected 5% of the time
a
The average life expectancy of tires produced by Whitney Tire Company has been 40,000
miles. Management believes that due to a new production process, the life expectancy of its
tires has increased. In order to test the validity of this belief, the correct set of hypotheses is
_____.
A.
Ho: μ ≤ 40,000 Ha: μ > 40,000
B.
H0: μ < 40,000 Ha: μ ≥ 40,000
C.
Ho: μ ≥ 40,000 Ha: μ < 40,000
D.
Ho: μ > 40,000 Ha: μ ≤ 40,000
a
More evidence against H0 is indicated by
A.
higher p-values
B.
lower probabilities of a Type II error
C.
smaller p-values
D.
lower levels of significance
c
The school's newspaper reported that the proportion of students majoring in business is at
least 30%. You plan on taking a sample to test the newspaper's claim. The correct set of
hypotheses is _____.
, A. Ho: p < .30 Ha: p ≥ .30
B. Ho: p ≤ .30 Ha: p > .30
C. Ho: p ≥ .30 Ha: p < .30
D. Ho: p > .30 Ha: p ≤ .30
c
If conducting a hypothesis test for Ho: mu = 10 versus Ha: mu /= 10 at the .05 level of
significance, rejecting Ho would mean the following:
A.
a 95% confidence interval for the population mean would contain the value of 10 within its
limits.
B.
a 95% confidence interval for the population mean would NOT contain the value of 10
within its limits.
C.
creating a 95% confidence interval would yield inconclusive results.
b
A p-value is the
A.
value of the test statistic
B.
probability of a Type II error
C.
probability, when the null hypothesis is true, of obtaining a sample result that is at least as
unlikely as what is observed
D.
probability corresponding to the critical value(s) in a hypothesis test
c
When the p-value < α, we reject the null hypothesis.
TrueFalse
CORRECT ANSWERS!!
In hypothesis testing if the null hypothesis is rejected, _____.
A. the alternative hypothesis must also be rejected
B. the evidence supports the alternative hypothesis
C. no conclusions can be drawn from the test
D. the data must have been collected incorrectly
B
In the hypothesis testing procedure, α (alpha) is
A.
the level of significance
B.
1 - level of significance
C.
the critical value
D.
the confidence level
a
If Ho is not rejected at a 5% level of significance, it _____. (Hint: Draw the picture and
think about it.)
A. will also not be rejected at the 1% level
B. will always be rejected at the 1% level
C. will sometimes be rejected at the 1% level
a
f a hypothesis test has a Type I error probability of .05, that means if the null hypothesis is
_____.
A. true, it will be rejected 5% of the time
B. true, it will not be rejected 5% of the time
,C. false, it will not be rejected 5% of the time
D. false, it will be rejected 5% of the time
a
The average life expectancy of tires produced by Whitney Tire Company has been 40,000
miles. Management believes that due to a new production process, the life expectancy of its
tires has increased. In order to test the validity of this belief, the correct set of hypotheses is
_____.
A.
Ho: μ ≤ 40,000 Ha: μ > 40,000
B.
H0: μ < 40,000 Ha: μ ≥ 40,000
C.
Ho: μ ≥ 40,000 Ha: μ < 40,000
D.
Ho: μ > 40,000 Ha: μ ≤ 40,000
a
More evidence against H0 is indicated by
A.
higher p-values
B.
lower probabilities of a Type II error
C.
smaller p-values
D.
lower levels of significance
c
The school's newspaper reported that the proportion of students majoring in business is at
least 30%. You plan on taking a sample to test the newspaper's claim. The correct set of
hypotheses is _____.
, A. Ho: p < .30 Ha: p ≥ .30
B. Ho: p ≤ .30 Ha: p > .30
C. Ho: p ≥ .30 Ha: p < .30
D. Ho: p > .30 Ha: p ≤ .30
c
If conducting a hypothesis test for Ho: mu = 10 versus Ha: mu /= 10 at the .05 level of
significance, rejecting Ho would mean the following:
A.
a 95% confidence interval for the population mean would contain the value of 10 within its
limits.
B.
a 95% confidence interval for the population mean would NOT contain the value of 10
within its limits.
C.
creating a 95% confidence interval would yield inconclusive results.
b
A p-value is the
A.
value of the test statistic
B.
probability of a Type II error
C.
probability, when the null hypothesis is true, of obtaining a sample result that is at least as
unlikely as what is observed
D.
probability corresponding to the critical value(s) in a hypothesis test
c
When the p-value < α, we reject the null hypothesis.
TrueFalse
