Question 1

What is the test statistic calculated by the statistical procedure selected known as?
A) Critical value
B) Significance level
C) Obtained value
D) p value

Accepted Answer

The test statistic calculated by the statistical procedure selected is known as the obtained value. This value is compared against a critical value or used to calculate a p-value to determine statistical significance.

Question 2

What is the formula used to calculate degrees of freedom for a t test for dependent groups?
A) n₁ - 1
B) n₁ + n₂ - 1
C) n₁ - 1 + n₂
D) n₁ + n₂

Accepted Answer

The formula for calculating degrees of freedom for a t-test for dependent groups (also known as a paired samples t-test) is n₁ - 1, where n₁ represents the number of paired observations. This is because the test compares two sets of data that are related and thus uses the number of pairs minus one to calculate the degrees of freedom.

Question 3

What does the Excel function TTEST compute?
A) t value
B) Probability of the t value occurring
C) Critical t value
D) Obtained t value

Accepted Answer

The Excel function TTEST computes the probability associated with the Student's t-test, determining whether two samples are likely to have come from the same two underlying populations that have the same mean.

Question 4

What is used to examine the degree of relationship between variables?
A) Hypothesized mean difference
B) Pearson correlation
C) Observations
D) Variance

Accepted Answer

Pearson correlation is the statistical measure used to examine the degree of relationship between variables, indicating the strength and direction of the linear relationship between two variables.

Question 5

In the following, what are the degrees of freedom: t???? = 2.001, p < .05?
A) 29
B) 30
C) 31
D) 32

Accepted Answer

The degrees of freedom (df) for a t-test are typically calculated as the sample size minus one. Given that t???? = 2.001 with a significance level (p < .05), without additional context, the exact sample size or the nature of the test (e.g., one-sample, independent, or paired t-test) is not provided. However, if we infer that the degrees of freedom are directly provided or hinted at by the question, the closest we can get is to assume that the degrees of freedom mentioned are part of the result output, which would imply a sample size of 30 (since df = n - 1, thus df = 29 suggests a sample size of 30).

Question 6

In a t test for dependent samples that examines the difference between a pretest and posttest, what type of hypothesis is used?
A) Nondirectional
B) Directional
C) Null
D) Research

Accepted Answer

The answer of In a t test for dependent samples...

Question 7

If the obtained value is less than the critical value, what should you do?
A) Reject the null hypothesis
B) Accept the null hypothesis
C) Reduce the p value
D) Decrease your sample

Accepted Answer

If the obtained value is less than the critical value, this means that the probability of obtaining the result by chance is very low. Therefore, we fail to reject the null hypothesis, which suggests no significant difference between the groups being compared. Accepting the null hypothesis means that we assume there is no difference between the groups.

Question 8

To compute the test statistic or t value you must first approximate the sample size through calculating the?
A) Pooled variance
B) Standard deviation
C) Degrees of freedom
D) Mean score

Accepted Answer

To compute the test statistic or t value, you need to know the degrees of freedom, which can be approximated by calculating the sample size.

Question 9

What is another name for a dependent samples t test?
A) Paired sample
B) Two sample
C) Independent sample
D) Freed sample

Accepted Answer

A dependent samples t test is also known as a paired sample t test because it involves comparing two related samples or sets of data that are paired or matched in some way. This test is used to determine if there is a significant difference between the means of two related variables or conditions.

Question 10

What is another name that statisticians call dependent tests?
A) Regression
B) Correlation
C) Repeated measures
D) Group differences

Accepted Answer

Dependent tests are also known as repeated measures, meaning that the same individuals are measured multiple times under different conditions.

Question 11

How many subjects were examined based on the following: t₍₂₉₎ = 2.001, p < .05? A) 29 B) 30 C) 31 D) 32

Accepted Answer

The answer of How many subjects were examined based on...

Question 12

How many observations are there for each case in a t test for dependent samples?
A) One
B) Two
C) Three
D) Four

Accepted Answer

In a t test for dependent samples, there are two observations for each case. The two observations represent the dependent variable measured at two different time points or under two different conditions for the same individuals.

Question 13

Which of the following represents degrees of freedom?
A) fd
B) df
C) d
D) f

Accepted Answer

df stands for degrees of freedom in statistics.

Question 14

If the obtained value is greater than the critical value, what should you do?
A) Reject the null hypothesis
B) Accept the null hypothesis
C) Set a higher p value
D) Increase your sample

Accepted Answer

If the obtained value is greater than the critical value, it means that the likelihood of obtaining the result by chance is too low (i.e., the p-value is less than the significance level). Therefore, we reject the null hypothesis and accept the alternative hypothesis.

Question 15

What Excel function requires that you enter the t value, degrees of freedom, and the number of tails?
A) TTEST
B) TEST2
C) TDIST
D) TDIST2

Accepted Answer

The TDIST function in Excel requires you to enter the t value, degrees of freedom, and the number of tails (either 1 or 2) to calculate the probability associated with a Student's t-distribution.

Question 16

To determine whether the null hypothesis should be rejected, the test statistic must be compared against which of these?
A) Critical value
B) Significance level
C) Obtained value
D) p value

Accepted Answer

The critical value is the value used to determine whether to reject the null hypothesis or not. It is based on the chosen level of significance and the degrees of freedom. If the test statistic is greater than the critical value, then the null hypothesis is rejected.

Question 17

To examine one group of subjects under two different conditions, which statistical technique should you select?
A) Regression
B) t test for dependent samples
C) Analysis of variance
D) t test for independent samples

Accepted Answer

The t test for dependent samples is used to compare the means of two related groups (e.g. same subjects tested under two different conditions). Regression is used to examine the relationship between two or more variables. Analysis of variance is used for comparing the means of more than two groups. The t test for independent samples is used to compare the means of two independent groups.

Question 18

In order to be 99% confident you have not committed a Type I error, at what level should you set your p value?
A) .01
B) .10
C) .05
D) .15

Accepted Answer

Setting your p value at .01 means that there is only a 1% chance that any significant results were found by chance (Type I error). This is a more conservative approach than setting the p value at .05 or .10.

Question 19

In the formula that computes a t value, what does n?D represent?
A) Sum of the difference between groups
B) Sum of the means for Group 1
C) Sum of the means for Group 2
D) Sum of the differences squared

Accepted Answer

n?D represents the sum of the differences between groups in the context of a t-test, which is used to compare the means of two groups to see if they are significantly different from each other.

Question 20

Which of the following relates to the difference you expect?
A) Hypothesized mean diff.
B) Pearson correlation
C) Observations
D) Variance

Accepted Answer

Hypothesized mean difference is the expected difference between two groups or conditions.

Answer: D 
 Variance is a measure of how spread out a set of data is, and can help indicate the magnitude of the difference between groups or conditions.

Quiz 12: t(ea) for Two (Again): Tests Between the Means of Related Groups

What is the test statistic calculated by the statistical procedure selected known as?

What is the formula used to calculate degrees of freedom for a t test for dependent groups?

What does the Excel function TTEST compute?

What is used to examine the degree of relationship between variables?

In the following, what are the degrees of freedom: t???? = 2.001, p < .05?

In a t test for dependent samples that examines the difference between a pretest and posttest, what type of hypothesis is used?

If the obtained value is less than the critical value, what should you do?

To compute the test statistic or t value you must first approximate the sample size through calculating the?

What is another name for a dependent samples t test?

What is another name that statisticians call dependent tests?

How many subjects were examined based on the following: t(29) = 2.001, p < .05?

How many observations are there for each case in a t test for dependent samples?

Which of the following represents degrees of freedom?

If the obtained value is greater than the critical value, what should you do?

What Excel function requires that you enter the t value, degrees of freedom, and the number of tails?

To determine whether the null hypothesis should be rejected, the test statistic must be compared against which of these?

To examine one group of subjects under two different conditions, which statistical technique should you select?

In order to be 99% confident you have not committed a Type I error, at what level should you set your p value?

In the formula that computes a t value, what does n?D represent?

Which of the following relates to the difference you expect?

How many subjects were examined based on the following: t₍₂₉₎ = 2.001, p < .05?