Question 1

A point estimate

Accepted Answer

A point estimate is a single value that is used to estimate an unknown population parameter, such as a mean or proportion. It is not a range of values (C), nor does it have a specified degree of confidence (D). While population data may be used to calculate a point estimate, it is not necessarily based solely on population data (A).

Question 2

Sample statistics are not expected to predict with certainty the values of the population because of

Accepted Answer

Sample statistics are subject to sampling error, which is the natural variability that occurs when taking a sample from a larger population. This means that sample statistics can only provide estimates of population parameters, and not precise predictions. Experimenter error, confidence error, and interval error are not the primary reasons why sample statistics cannot predict population values with certainty.

Question 3

A sample mean used to predict a population mean is an example of a

Accepted Answer

A sample mean used to predict a population mean is an example of a point estimate, as it uses information from a sample to estimate a single value (the population mean).

Question 4

Which of the following is NOT true of confidence intervals?

Accepted Answer

Confidence intervals are less specific than point estimates, as they provide a range of possible values for the population parameter rather than a single value.

Question 5

Which of the following is NOT true of point estimates?

Accepted Answer

Point estimates do not include adjustments for standard error. They simply provide a single value as an estimate for the parameter of interest in the population based on the sample data. Confidence intervals, on the other hand, do include adjustments for standard error and provide a range of values within which the true population parameter is likely to lie. Option A and B are true as point estimates are based on sample data and used to estimate population parameters, and option D is true as confidence intervals are more specific than point estimates as they provide a range of values rather than a single value.

Question 6

Point estimates involve _______ values and are _______ specific than confidence intervals.

Accepted Answer

Point estimates refer to a single value that estimates a population parameter, whereas confidence intervals give a range of values that the parameter is likely to fall within. Therefore, point estimates are less specific than confidence intervals because they do not provide a range of values.

Question 7

To determine the point estimate of a population parameter, use

Accepted Answer

The point estimate of a population parameter is typically the sample statistic itself, which is the numerator of the t test when estimating a mean.

Question 8

For a one-sample t test, the point estimate would be

Accepted Answer

The point estimate for a one-sample t test would be the sample mean (M).

Question 9

For an independent samples t test, the point estimate would be

Accepted Answer

The point estimate for an independent samples t test is the difference between the means of two groups (M₁ - M₂). Therefore, the correct choice is B.

Question 10

For a repeated measures t test, the point estimate would be

Accepted Answer

The point estimate for a repeated measures t-test is the mean of the differences (M_D) between paired observations.

Question 11

Confidence intervals are _______ specific than point estimates and involve _______ values.

Accepted Answer

Confidence intervals are less specific than point estimates because they provide a range of values within which the true parameter is expected to lie, rather than a single value.

Question 12

Which of the following components is not needed for calculating the lower and upper limits of a confidence interval?

Accepted Answer

To calculate the lower and upper limits of a confidence interval, we need an obtained statistic, a t-value, and the estimated standard error. The population parameter is not needed, as we are using the sample statistic to estimate it with a certain level of confidence.

Question 13

If we want to establish a 99% confidence interval for the population mean, then our interval would fail to capture μ _____ percent of the time.

Accepted Answer

A 99% confidence interval means that in repeated sampling, 99% of the intervals will capture the true population mean and 1% of the intervals will not. Therefore, the answer is A) 1.

Question 14

Which is the correct formula for the upper limit of a confidence interval for a one-sample t test?

Accepted Answer

The upper limit of a confidence interval for a one-sample t-test is calculated using the sample mean (M) plus the product of the t-value and the standard error of the mean (s_M).

Question 15

Which is the correct formula for the lower limit of a confidence interval for an independent samples t test?

Accepted Answer

The correct formula for the lower limit of a confidence interval for an independent samples t-test involves the difference between the sample means (M₁ - M₂), subtracting the product of the t-value and the standard error of the difference between the means. Option D correctly represents this formula.

Question 16

Which is the correct formula for the lower limit of a confidence interval for a repeated measures t test?

Accepted Answer

The correct formula for the lower limit of a confidence interval for a repeated measures t test is M_D - t (s_{M_D}), where M_D is the mean difference, t is the t-value from the t-distribution, and s_{M_D} is the standard error of the mean difference.

Question 17

Given the scores 10, 12, 15, and 20, what is the point estimate for μ?

Accepted Answer

The point estimate for μ is the sample mean, which is calculated by adding up all the scores and dividing by the sample size. (10+12+15+20)/4 = 14.25. Therefore, the answer is B. Option D is incorrect because μ is a population parameter and cannot have a plus-minus sign. Option A and C are incorrect as they are just the sum of all the scores and cannot be the point estimate for μ.

Question 18

The scores for group one in a study are 4, 5, 6, and 7. The scores for group two are 8, 9, 10, 11, and 12. What would the point estimate be for an independent samples t test?

Accepted Answer

The point estimate for an independent samples t-test is the difference between the means of the two groups. The mean of group one is (4+5+6+7)/4 = 5.5, and the mean of group two is (8+9+10+11+12)/5 = 10. The point estimate is 5.5 - 10 = -4.5.

Question 19

The pre-test scores for a repeated measures test were 6, 8, 10, and 9. The post-test scores for the same participants in the same order were 8, 10, 11, and 12. What would be point estimate be for μ_D?

Accepted Answer

To calculate μ_D, we need to first calculate the differences between post-test and pre-test scores for each participant, and then take the mean of those differences. Participant 1: 8-6 = 2 Participant 2: 10-8 = 2 Participant 3: 11-10 = 1 Participant 4: 12-9 = 3 Mean difference: (2+2+1+3)/4 = 2 Therefore, the point estimate for μ_D is +2.00.

Question 20

If we wanted to estimate a 90% confidence interval for a one-sample t test with a sample of n = 18, what t-values would we use?

Accepted Answer

The t-value for a 90% confidence interval with a sample size of 18 is ±1.740.

Quiz 12: Confidence Interval Versus Point Estimation

A point estimate

Sample statistics are not expected to predict with certainty the values of the population because of

A sample mean used to predict a population mean is an example of a

Which of the following is NOT true of confidence intervals?

Which of the following is NOT true of point estimates?

Point estimates involve _ values and are _ specific than confidence intervals.

To determine the point estimate of a population parameter, use

For a one-sample t test, the point estimate would be

For an independent samples t test, the point estimate would be

For a repeated measures t test, the point estimate would be

Confidence intervals are _ specific than point estimates and involve _ values.

Which of the following components is not needed for calculating the lower and upper limits of a confidence interval?

If we want to establish a 99% confidence interval for the population mean, then our interval would fail to capture μ _____ percent of the time.

Which is the correct formula for the upper limit of a confidence interval for a one-sample t test?

Which is the correct formula for the lower limit of a confidence interval for an independent samples t test?

Which is the correct formula for the lower limit of a confidence interval for a repeated measures t test?

Given the scores 10, 12, 15, and 20, what is the point estimate for μ?

The scores for group one in a study are 4, 5, 6, and 7. The scores for group two are 8, 9, 10, 11, and 12. What would the point estimate be for an independent samples t test?

The pre-test scores for a repeated measures test were 6, 8, 10, and 9. The post-test scores for the same participants in the same order were 8, 10, 11, and 12. What would be point estimate be for μ_D?

If we wanted to estimate a 90% confidence interval for a one-sample t test with a sample of n = 18, what t-values would we use?

Quiz 12: Confidence Interval Versus Point Estimation

A point estimate

Sample statistics are not expected to predict with certainty the values of the population because of

A sample mean used to predict a population mean is an example of a

Which of the following is NOT true of confidence intervals?

Which of the following is NOT true of point estimates?

Point estimates involve _______ values and are _______ specific than confidence intervals.

To determine the point estimate of a population parameter, use

For a one-sample t test, the point estimate would be

For an independent samples t test, the point estimate would be

For a repeated measures t test, the point estimate would be

Confidence intervals are _______ specific than point estimates and involve _______ values.

Which of the following components is not needed for calculating the lower and upper limits of a confidence interval?

If we want to establish a 99% confidence interval for the population mean, then our interval would fail to capture μ _____ percent of the time.

Which is the correct formula for the upper limit of a confidence interval for a one-sample t test?

Which is the correct formula for the lower limit of a confidence interval for an independent samples t test?

Which is the correct formula for the lower limit of a confidence interval for a repeated measures t test?

Given the scores 10, 12, 15, and 20, what is the point estimate for μ?

The scores for group one in a study are 4, 5, 6, and 7. The scores for group two are 8, 9, 10, 11, and 12. What would the point estimate be for an independent samples t test?

The pre-test scores for a repeated measures test were 6, 8, 10, and 9. The post-test scores for the same participants in the same order were 8, 10, 11, and 12. What would be point estimate be for μD?

If we wanted to estimate a 90% confidence interval for a one-sample t test with a sample of n = 18, what t-values would we use?

Point estimates involve _ values and are _ specific than confidence intervals.

Confidence intervals are _ specific than point estimates and involve _ values.

The pre-test scores for a repeated measures test were 6, 8, 10, and 9. The post-test scores for the same participants in the same order were 8, 10, 11, and 12. What would be point estimate be for μ_D?