EPPP Questions Research and Statistics Graded A+
R squared is known as:
Answer Choices:
- a. coefficient of multiple determination
- b. coefficient of stability
- c. coefficient of internal consistency
- d. silver character on "Star Wars"
Correct Answer: a. coefficient of multiple determination
---
When data points are widely scattered around a regression line, it indicates:
Answer Choices:
- a. low homoscedasticity
- b. low correlation coefficient
- c. low heteroscedasticity
- d. high heteroscedasticity
Correct Answer: b. low correlation coefficient
Rationale: The uneven scatter around the regression line signifies a weak linear relationship.
---
Heteroscedasticity refers to:
,Correct Answer: The scatter is uneven (unequal) at different points on the regression line. Variability
may differ across the range of the predictor variable, indicating inconsistency in the relationships at
various levels.
---
In a study evaluating the effects of a new drug on psychotic patients' social behavior, the best method to
reduce experimenter bias is:
Answer Choices:
- a. randomized block design
- b. a Solomon four-group design
- c. counterbalancing
- d. a double-blind study
Correct Answer: d. a double-blind study
Rationale: This design ensures that neither participants nor experimenters know who receives the
treatment, minimizing bias.
---
Which measure indicates the "amount of variability accounted for"?
Answer Choices:
- a. Cohen's d
- b. F-ratio
- c. alpha
- d. eta squared
Correct Answer: d. eta squared
,Rationale: Eta squared quantifies the proportion of variance explained by an independent variable in
relation to a dependent variable.
---
The eta coefficient would be used to:
Answer Choices:
- a. estimate the strength of a nonlinear relationship between two continuous variables
- b. estimate the strength of the relationship between two rank-ordered variables
- c. estimate the strength of the relationship between two dichotomous variables
- d. estimate the strength of the relationship between a dichotomous variable and a continuous variable
Correct Answer: a. estimate the strength of a nonlinear relationship between two continuous variables.
---
The most common correlation coefficient is:
Correct Answer: Pearson r
Rationale: Pearson's r is utilized to assess linear relationships between two continuous variables.
Note: Eta is used for nonlinear relationships.
---
Phi Coefficient is used to measure:
, Rationale: It quantifies the correlation between two dichotomous variables, while Point-Biserial
Correlation measures the relationship between a dichotomous variable and a continuous variable, and
Spearman's rho is employed for ranked data correlation.
---
You have found a significant correlation between salary and job performance. If you are informed about
a $25.00 cost of living raise that every employee received, you should:
Answer Choices:
- a. assume the correlation will not be affected
- b. not be concerned since the added amount is too small to make a significant difference
- c. decide that the raise invalidated the research
- d. reanalyze the data after the raises have been added to the current salaries.
Correct Answer: a. assume the correlation will not be affected
Rationale: Adding a constant to each score does not alter the correlation between the variables.
---
A psychological researcher aiming to distinguish variables that separate patients who benefit from
psychotherapy from those who do not would likely use:
Answer Choices:
- a. canonical correlation
- b. factor analysis
- c. MANOVA
- d. discriminant function analysis
Correct Answer: d. discriminant function analysis
R squared is known as:
Answer Choices:
- a. coefficient of multiple determination
- b. coefficient of stability
- c. coefficient of internal consistency
- d. silver character on "Star Wars"
Correct Answer: a. coefficient of multiple determination
---
When data points are widely scattered around a regression line, it indicates:
Answer Choices:
- a. low homoscedasticity
- b. low correlation coefficient
- c. low heteroscedasticity
- d. high heteroscedasticity
Correct Answer: b. low correlation coefficient
Rationale: The uneven scatter around the regression line signifies a weak linear relationship.
---
Heteroscedasticity refers to:
,Correct Answer: The scatter is uneven (unequal) at different points on the regression line. Variability
may differ across the range of the predictor variable, indicating inconsistency in the relationships at
various levels.
---
In a study evaluating the effects of a new drug on psychotic patients' social behavior, the best method to
reduce experimenter bias is:
Answer Choices:
- a. randomized block design
- b. a Solomon four-group design
- c. counterbalancing
- d. a double-blind study
Correct Answer: d. a double-blind study
Rationale: This design ensures that neither participants nor experimenters know who receives the
treatment, minimizing bias.
---
Which measure indicates the "amount of variability accounted for"?
Answer Choices:
- a. Cohen's d
- b. F-ratio
- c. alpha
- d. eta squared
Correct Answer: d. eta squared
,Rationale: Eta squared quantifies the proportion of variance explained by an independent variable in
relation to a dependent variable.
---
The eta coefficient would be used to:
Answer Choices:
- a. estimate the strength of a nonlinear relationship between two continuous variables
- b. estimate the strength of the relationship between two rank-ordered variables
- c. estimate the strength of the relationship between two dichotomous variables
- d. estimate the strength of the relationship between a dichotomous variable and a continuous variable
Correct Answer: a. estimate the strength of a nonlinear relationship between two continuous variables.
---
The most common correlation coefficient is:
Correct Answer: Pearson r
Rationale: Pearson's r is utilized to assess linear relationships between two continuous variables.
Note: Eta is used for nonlinear relationships.
---
Phi Coefficient is used to measure:
, Rationale: It quantifies the correlation between two dichotomous variables, while Point-Biserial
Correlation measures the relationship between a dichotomous variable and a continuous variable, and
Spearman's rho is employed for ranked data correlation.
---
You have found a significant correlation between salary and job performance. If you are informed about
a $25.00 cost of living raise that every employee received, you should:
Answer Choices:
- a. assume the correlation will not be affected
- b. not be concerned since the added amount is too small to make a significant difference
- c. decide that the raise invalidated the research
- d. reanalyze the data after the raises have been added to the current salaries.
Correct Answer: a. assume the correlation will not be affected
Rationale: Adding a constant to each score does not alter the correlation between the variables.
---
A psychological researcher aiming to distinguish variables that separate patients who benefit from
psychotherapy from those who do not would likely use:
Answer Choices:
- a. canonical correlation
- b. factor analysis
- c. MANOVA
- d. discriminant function analysis
Correct Answer: d. discriminant function analysis
