Statistics final exam
1. In principle, how is a confidence interval for a population proportion calculated after a
sample has been taken and analyzed?
● The sample proportion is calculated, then the appropriate sampling error is
subtracted from it to create a lower bound of the interval, and then separately
the Sampling Error is added to the sample proportion to create the upper
bound of the interval.
● The population proportion is calculated, then the appropriate margin of error is
subtracted from it to create the lower bound of the interval, and then separately
the margin of error is added to the sample proportion to create the upper bound
of the interval.
● The population proportion is calculated, then the appropriate sampling error is
subtracted from it to create the lower bound of the interval, and then separately
the sampling error is added to the sample proportion to create the upper bound
of the interval.
● The sample proportion is calculated, then the appropriate margin of error
is subtracted from it to create the lower bound of the interval, and then
separately the margin of error is added to the sample proportion to create
the upper bound of the interval
2. In a sample of 200 women between 30 - 40 years of age, 85 of them had high blood
pressure. If p-hat represents the proportion of women with high blood pressure, then
q-hat would equal what value?
● 0.58
● 85
● 0.43
● 115
3. When computing a confidence interval for the difference of two proportions, what
would be the point estimate be?
● z(SE)
● The difference of the population proportions
● The difference of the sample proportions
● Zero
4. Which of the following statements are false about the alternative hypotheses when
testing for a difference between two population proportions?
● I. The alternative hypothesis states that the two population proportions
are equal.
● II. The alternative hypothesis may state that the two population proportions are
not equal.
● III. The alternative hypothesis may state that one population proportion is
greater than the other population proportion.
, ● IV. The alternative hypotheses must always be written as a two-sided
statement.
● V. The alternative hypothesis can describe a direction of difference between
the two population proportions.
● VI. The alternative hypothesis is formulated under the assumption that
the null hypothesis is true
Correct answer: I, IV, and VI
5. In setting up a confidence interval on the difference between two proportions, you
find your point estimate to be 0.63 and the margin of error to be 0.05. Determine your
95% confidence interval. Round to 2 decimal places as needed.
● (0.50, 0.75)
● (0.53, 0.73)
● (0.58, 0.68)
● (0.55, 0.71)
6. In setting up a confidence interval on the difference between two proportions, you
find your point estimate to be 0.09 and the standard error to be 0.03. Determine your
95% confidence interval. Round to 2 decimal places as needed.
● (0.03, 0.15)
● (0. 075, 0.105)
● (0.06, 0.12)
● Cannot determine. Not enough information
7. In a Chi-squared hypothesis test, the null hypothesis is stating that the proportions are
equal to what was observed.
● True
● False, the null hypothesis is stating that the proportions are equal to 0.
● False, the null hypothesis is stating that the proportions are equal to each other.
● False, the null hypothesis is stating that the proportions are equal to what
was expected.
8. In doing a Chi-squared hypothesis test, there are 7 degrees of freedom. Therefore, the
number of categories would be which value?
● 5
● 6
● 8
● 7
9. In a Chi-Squared hypothesis test, you find the Chi-Squared critical value at a level of
significance of 0.05 and 9 degrees of freedom to be 16.92. You find your test statistic
to be 17. Which of the following statements represents your conclusion?
● Cannot determine as it is not stated whether this is a one-tail or two-tail test.
1. In principle, how is a confidence interval for a population proportion calculated after a
sample has been taken and analyzed?
● The sample proportion is calculated, then the appropriate sampling error is
subtracted from it to create a lower bound of the interval, and then separately
the Sampling Error is added to the sample proportion to create the upper
bound of the interval.
● The population proportion is calculated, then the appropriate margin of error is
subtracted from it to create the lower bound of the interval, and then separately
the margin of error is added to the sample proportion to create the upper bound
of the interval.
● The population proportion is calculated, then the appropriate sampling error is
subtracted from it to create the lower bound of the interval, and then separately
the sampling error is added to the sample proportion to create the upper bound
of the interval.
● The sample proportion is calculated, then the appropriate margin of error
is subtracted from it to create the lower bound of the interval, and then
separately the margin of error is added to the sample proportion to create
the upper bound of the interval
2. In a sample of 200 women between 30 - 40 years of age, 85 of them had high blood
pressure. If p-hat represents the proportion of women with high blood pressure, then
q-hat would equal what value?
● 0.58
● 85
● 0.43
● 115
3. When computing a confidence interval for the difference of two proportions, what
would be the point estimate be?
● z(SE)
● The difference of the population proportions
● The difference of the sample proportions
● Zero
4. Which of the following statements are false about the alternative hypotheses when
testing for a difference between two population proportions?
● I. The alternative hypothesis states that the two population proportions
are equal.
● II. The alternative hypothesis may state that the two population proportions are
not equal.
● III. The alternative hypothesis may state that one population proportion is
greater than the other population proportion.
, ● IV. The alternative hypotheses must always be written as a two-sided
statement.
● V. The alternative hypothesis can describe a direction of difference between
the two population proportions.
● VI. The alternative hypothesis is formulated under the assumption that
the null hypothesis is true
Correct answer: I, IV, and VI
5. In setting up a confidence interval on the difference between two proportions, you
find your point estimate to be 0.63 and the margin of error to be 0.05. Determine your
95% confidence interval. Round to 2 decimal places as needed.
● (0.50, 0.75)
● (0.53, 0.73)
● (0.58, 0.68)
● (0.55, 0.71)
6. In setting up a confidence interval on the difference between two proportions, you
find your point estimate to be 0.09 and the standard error to be 0.03. Determine your
95% confidence interval. Round to 2 decimal places as needed.
● (0.03, 0.15)
● (0. 075, 0.105)
● (0.06, 0.12)
● Cannot determine. Not enough information
7. In a Chi-squared hypothesis test, the null hypothesis is stating that the proportions are
equal to what was observed.
● True
● False, the null hypothesis is stating that the proportions are equal to 0.
● False, the null hypothesis is stating that the proportions are equal to each other.
● False, the null hypothesis is stating that the proportions are equal to what
was expected.
8. In doing a Chi-squared hypothesis test, there are 7 degrees of freedom. Therefore, the
number of categories would be which value?
● 5
● 6
● 8
● 7
9. In a Chi-Squared hypothesis test, you find the Chi-Squared critical value at a level of
significance of 0.05 and 9 degrees of freedom to be 16.92. You find your test statistic
to be 17. Which of the following statements represents your conclusion?
● Cannot determine as it is not stated whether this is a one-tail or two-tail test.
