Question 1

Dr. Castillo is interested in examining all possible combinations of conditions in his study examining obedience to authority for different generations. His initial analyses yielded significant results. Dr. Castillo is interested in:

Accepted Answer

Post-hoc analyses are conducted after initial analyses reveal significant results, to explore all possible combinations of conditions or groups in a study. This is consistent with Dr. Castillo's interest in examining all possible combinations of conditions in his study on obedience to authority across different generations.

Question 2

Dr. Copeland noted the following results in her manuscript: F(3, 116) = .80, p = .01, eta²= .27. Which of the following numbers represents between-subjects degrees of freedom in this results write-up?

Accepted Answer

In the notation F(3, 116), the first number (3) represents the between-subjects degrees of freedom, which is related to the number of groups or conditions being compared.

Question 3

Dr. Crouse made specific predictions in the development phase of his study regarding which comparisons between conditions would yield significant results. Dr. Crouse conducted _____ to produce such data.

Accepted Answer

Planned contrasts involve making specific predictions before collecting data, which aligns with Dr. Crouse's approach of predicting significant results between conditions in the development phase of his study.

Question 4

Warren randomly assigned 60 participants to describe a positive childhood memory, a negative childhood memory, or a neutral childhood memory and then complete a mood questionnaire. Warrens wants to compare the "neutral condition" with the other two conditions. Which statistic is appropriate to use?

Accepted Answer

A planned contrast is appropriate because Warren has specific hypotheses about the differences between the neutral condition and the other two conditions (positive and negative). This allows for direct comparison of the neutral condition against the combined effects of the other conditions, fitting the scenario described.

Question 5

Beck randomly assigned 60 participants to describe a positive childhood memory, a negative childhood memory, or a neutral childhood memory and then complete a mood questionnaire. Beck wants the overall differences between groups. Which statistic is appropriate to use?

Accepted Answer

A one-way ANOVA is appropriate because Beck is comparing the means of more than two independent groups to see if there is a statistically significant difference among them.

Question 6

Dr. Spruill conducted a one-way ANOVA on a set of data examining political opinions after participants watched different propaganda footage from different eras. Each condition saw a different reel of footage and one condition simply watched a movie with no political agenda. Dr. Spruill's one-way ANOVA yielded significant results, but it was not able to tell him where the specific difference existed. Dr. Spruill will need to follow-up with which analysis to test all possible combinations of the conditions?

Accepted Answer

Post-hoc analyses are used after a significant ANOVA result to determine exactly where the differences between groups lie, by comparing all possible pairs of groups.

Question 7

The variable must be _____ in order to conduct a chi-square test of independence.

Accepted Answer

The chi-square test of independence requires that the variable be nominal (or categorical) because it compares frequencies of categories between different groups to see if there's a significant association between them.

Question 8

Dr. Pantoja conducted a chi-square test of independence between conditions to determine if the distribution among 175 participants was as expected. Dr. Pantoja was studying sleep cycles for various age groups with and without sleep apnea. Dr. Pantoja's results did not yield a significant result. Which of the following would be the most accurate results write-up for a chi-square test of independence?

Accepted Answer

The correct choice is B because it reports a chi-square statistic (though the notation seems to be corrupted, it's intended to represent a chi-square result), a non-significant p-value (p = .55), which aligns with the statement that Dr. Pantoja's results did not yield a significant result. The inclusion of a phi coefficient (ᶲ = .30) is appropriate for chi-square tests of independence, providing a measure of effect size. Choices A and C report significant p-values, contradicting the premise, and choice D incorrectly uses F-statistic notation, which is associated with ANOVA, not chi-square tests.

Question 9

The F statistic included in a results write-up for a one-way ANOVA includes all of the following information, EXCEPT:

Accepted Answer

Cronbach's alpha is a measure of internal consistency or reliability of a scale, not information included in the F statistic for a one-way ANOVA. The F statistic itself, between-subjects degrees of freedom, and within-subjects degrees of freedom are all relevant to reporting ANOVA results.

Question 10

Which of the following is a results write-up for an ANOVA?

Accepted Answer

ANOVA results are typically reported using the F-statistic, degrees of freedom, p-value, and effect size (such as eta-squared). Option B provides these elements.

Question 11

Dr. Wadsworth used census data to estimate the number of individuals who would meet criteria for participation in his study. Dr. Wadsworth is examining both single-parent and two-parent families receiving federal assistance. One group includes single-parents currently seeking higher education and the other group includes two-parent households receiving federal assistance with either parent currently seeking higher education. Dr. Wadsworth expects 54 males and 72 females in his single-parent family group and 32 males and 44 females in his two-parent family group. After data collection is complete Dr. Wadsworth wants to make sure the distribution is not significantly different among the groups. Dr. Wadsworth needs to conduct a(n):

Accepted Answer

Dr. Wadsworth is comparing categorical data (gender and family type) to see if there's a significant difference in distribution among groups, which is best analyzed using a chi-square test of independence. This test is used to determine if there is a significant association between two categorical variables.

Question 12

Dr. Raymond is lecturing on various statistical analyses in class. She notes the definition for exploratory analyses as:

Accepted Answer

Exploratory analyses are characterized by the investigation of data to find patterns or relationships that were not specifically anticipated before the study began. This contrasts with confirmatory analyses, which test pre-specified hypotheses.

Question 13

Dr. Moye is lecturing on various statistical analyses in class. He notes the definition for planned contrasts as:

Accepted Answer

Planned contrasts involve statistical tests that are designed to compare specific groups or conditions based on hypotheses or predictions made before the data is collected, hence the term "a priori" decisions. These contrasts are used to test specific, preconceived theories or expectations about the relationships between groups.

Question 14

Dr. Copeland noted the following results in her manuscript: F(3, 116) = .80, p = .01, eta²= .27. Which of the following numbers represents the significance level in this result write-up?

Accepted Answer

The significance level in statistical results is denoted by "p". In this case, p = .01 indicates the significance level, showing the probability of observing the data if the null hypothesis were true.

Question 15

Dr. Copeland noted the following results in her manuscript: F(3, 116) = .80, p = .01, eta²= .27. Which of the following numbers represents the F score in this results write-up?

Accepted Answer

The F score in the results write-up is represented by the value immediately following the "F" notation, which in this case is .80.

Question 16

Dr. Copeland noted the following results in her manuscript: F(3, 116) = .80, p = .01, eta²= .27. Which of the following numbers represents within-subjects degrees of freedom in this results write-up?

Accepted Answer

The within-subjects degrees of freedom is represented by the second number in the F-statistic notation, which is 116 in this case.

Question 17

Dr. Eggleston is lecturing on various statistical analyses in class. He notes the definition for a chi-square test of independence as:

Accepted Answer

The chi-square test of independence is used to determine if there is a significant association between two categorical variables. It compares the observed frequencies in each category to the frequencies that would be expected if there were no association between the variables, matching the description in option A.

Question 18

Dr. Hsu conducted a one-way ANOVA on a set of data examining digestive reaction to the smell of food and watching food preparation. Dr. Hsu had multiple experimental conditions. Dr. Hsu's one-way ANOVA yielded significant results, but the analysis was not able to tell him where the specific differences existed. Dr. Hsu will need to follow-up with which analysis to test all possible combinations of the conditions?

Accepted Answer

Post-hoc analyses are used after a significant ANOVA result to determine where the specific differences between groups lie, especially when multiple experimental conditions are involved and all possible combinations of conditions need to be compared.

Question 19

Dr. Copeland noted the following results in her manuscript: F(3, 116) = .80, p = .01, eta²= .27. Which of the following numbers represents the effect size in this results write-up?

Accepted Answer

The effect size in this results write-up is represented by eta squared (η²), which is .27. This statistic measures the proportion of the variance in the dependent variable that is attributable to the independent variable.

Question 20

Dr. Reddick is lecturing on various statistical analyses in class. He notes the definition for post-hoc analyses as:

Accepted Answer

Post-hoc analyses are statistical tests conducted after an experiment has been completed to explore different patterns or comparisons that were not specified before the data was collected. They examine all possible combinations of conditions to find significant differences, accounting for the fact that these comparisons were not initially predicted.

Quiz 9: Multigroup Design: Im Feeling Hot, but Is the Earth Hot, Too