Question 6 (1 point)
The federal government recently granted funds for a special
program designed to reduce crime in high-crime areas. A study of
the results of the program in high-crime areas of Miami, Florida,
are being examined to test the effectiveness of the program. The
difference in crimes reported is calculated as (crimes after -
crimes before). You want to test whether the average number of
crimes reported after are greater than the average number of crimes
reported before. What are the hypotheses for this test?
Question 6 options:
Question 7 (1 point)
A medical researcher wants to examine the relationship of the
blood pressure of patients before and after a procedure. She takes
a sample of people and measures their blood pressure before
undergoing the procedure. Afterwards, she takes the same sample of
people and measures their blood pressure again. If the researcher
wants to test if the blood pressure measurements after the
procedure are different from the blood pressure measurements before
the procedure, what will the null and alternative hypotheses be?
Treat the differences as (blood pressure after - blood pressure
before).
Question 7 options:
Question 8 (1 point)
Will eating oatmeal promote healthy levels of cholesterol? A
consumer reports analyst took a sample of 50 people with high
cholesterol and asked them to eat oatmeal once a day for 3 months.
Measurements were taken of their cholesterol levels before and
after the 3 months in mg/dl. The analyst is testing whether the
cholesterol levels after the diet are different from the
cholesterol levels before the diet. The hypotheses for this test
are as follows: Null Hypothesis: μD = 0, Alternative
Hypothesis: μD ≠ 0. If the analyst calculated the mean
difference in cholesterol levels (after - before) to be 1.26 mg/dL
with a standard deviation of 8.56 md/dL, what is the test statistic
and p-value for the paired hypothesis t-test?
Question 8 options:
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1)
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Test Statistic: 1.041, P-Value: 0.1515 |
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2)
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Test Statistic: 1.041, P-Value: 1.8485 |
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3)
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Test Statistic: 1.041, P-Value: 0.303 |
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4)
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Test Statistic: 1.041, P-Value: 0.8485 |
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5)
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Test Statistic: -1.041, P-Value: 0.303 |
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Question 9 (1 point)
A medical researcher wants to examine the relationship of the
blood pressure of patients before and after a procedure. She takes
a sample of 29 people and measures their blood pressure before
undergoing the procedure. Afterwards, she takes the same sample of
people and measures their blood pressure again. The researcher
wants to test if the blood pressure measurements after the
procedure are different from the blood pressure measurements before
the procedure and, thus, the hypotheses are as follows: Null
Hypothesis: μD = 0, Alternative Hypothesis:
μD ≠ 0. If the average difference between the before and
after blood pressures (calculated as after - before) is 0.62 with a
standard deviation of 11.62, what is the test statistic and
p-value?
Question 9 options:
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1)
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Test Statistic: 0.287, P-Value: 0.776 |
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2)
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Test Statistic: -0.287, P-Value: 0.776 |
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3)
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Test Statistic: 0.287, P-Value: 0.388 |
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4)
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Test Statistic: 0.287, P-Value: 0.612 |
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5)
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Test Statistic: 0.287, P-Value: 1.612 |
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Question 10 (1 point)
You are looking for a way to incentivize the sales reps that you
are in charge of. You design an incentive plan as a way to help
increase in their sales. To evaluate this innovative plan, you take
a random sample of your reps, and their weekly incomes before and
after the plan were recorded. You calculate the difference in
income as (after incentive plan - before incentive plan). You
perform a paired samples t-test with the following hypotheses: Null
Hypothesis: μD≤ 0, Alternative Hypothesis: μD
> 0. You calculate a p-value of 0.3076. What is the appropriate
conclusion of your test?
Question 10 options:
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1)
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The average difference in weekly income is significantly larger
than 0. The average weekly income was higher after the incentive
plan. |
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2)
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The average difference in weekly income is less than or equal
to 0. |
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3)
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We did not find enough evidence to say there was a
significantly positive average difference in weekly income. The
incentive plan does not appear to have been effective. |
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4)
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We did not find enough evidence to say there was a
significantly negative average difference in weekly income. The
incentive plan does not appear to have been effective. |
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5)
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We did not find enough evidence to say the average difference
in weekly income was not 0. The incentive plan does not appear to
have been effective. |
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Question 11 (1 point)
You are looking for a way to incentivize the sales reps that you
are in charge of. You design an incentive plan as a way to help
increase in their sales. To evaluate this innovative plan, you take
a random sample of your reps, and their weekly incomes before and
after the plan were recorded. You calculate the difference in
income as (after incentive plan - before incentive plan). You
perform a paired samples t-test with the following hypotheses: Null
Hypothesis: μD≤ 0, Alternative Hypothesis: μD
> 0. You calculate a p-value of 0.0474. What is the appropriate
conclusion of your test?
Question 11 options:
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1)
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We did not find enough evidence to say there was a
significantly positive average difference in weekly income. The
incentive plan does not appear to have been effective. |
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2)
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The average difference in weekly income is significantly larger
than 0. The average weekly income was higher after the incentive
plan. |
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3)
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The average difference in weekly income is significantly
different from 0. There is a significant difference in weekly
income due to the incentive plan. |
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4)
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The average difference in weekly income is significantly less
than 0. The average weekly income was higher before the incentive
plan. |
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5)
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The average difference in weekly income is less than or equal
to 0. |
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Question 12 (1 point)
Consumers Energy states that the average electric bill across
the state is $62.74. You want to test the claim that the average
bill amount is actually less than $62.74. The hypotheses for this
situation are as follows: Null Hypothesis: μ ≥ 62.74, Alternative
Hypothesis: μ < 62.74. If the true statewide average bill is
$51.97 and the null hypothesis is not rejected, did a type I, type
II, or no error occur?
Question 12 options:
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1)
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We do not know the degrees of freedom, so we cannot determine
if an error has occurred. |
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2)
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Type I Error has occurred |
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3)
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We do not know the p-value, so we cannot determine if an error
has occurred. |
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4)
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No error has occurred. |
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5)
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Type II Error has occurred. |
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Question 13 (1 point)
Consumers Energy states that the average electric bill across
the state is $57.42. You want to test the claim that the average
bill amount is actually greater than $57.42. The hypotheses for
this situation are as follows: Null Hypothesis: μ ≤ 57.42,
Alternative Hypothesis: μ > 57.42. If the true statewide average
bill is $24.71 and the null hypothesis is rejected, did a type I,
type II, or no error occur?
Question 13 options:
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1)
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Type II Error has occurred |
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2)
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No error has occurred. |
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3)
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We do not know the degrees of freedom, so we cannot determine
if an error has occurred. |
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4)
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We do not know the p-value, so we cannot determine if an error
has occurred. |
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5)
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Type I Error has occurred. |
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