EPPP Questions Research and Statistics Questions
with Detailed Verified Answers for Accuracy
R squared is the:
a. coefficient of multiple determination
b. coefficient of stability
c. coefficient of internal consistency
d. silver character on "Star Wars"
✓✓ a. coefficient of multiple determination
When data points are widely scattered around a regression
line, this indicates:
a. low homoscedasticity
b. low correlation coefficient
c. low heteroscedasticity
d. high heteroscedasticity
✓✓ b. low correlation coefficient
Heteroscedasticity
✓✓ The scatter is uneven (unequal) at different points on the
regression line. For example, there might be high variability
around the regression line at low X (predictor) values and low
variability around the line at high X values. It is different
amounts of scatter, but not high scatter
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A psychologist in a hospital is conducting research designed to
assess the effects of a new drug on the social behavior of
psychotic patients. Which of the following would be the best
way to decrease experimenter bias in this type of study?
a. randomized block design
b. a Solomon four-group design
c. counterbalancing
d. a double-blind study
✓✓ d. a double blind study
Which of the following is a measure of "amount of variability
accounted for"?
a. Cohen's d
b. F-ratio
c. alpha
d. eta squared
✓✓ d. eta squared
Alpha
✓✓ Level of significance set by a researcher prior to analyzing
data
Cohen's d
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✓✓ Used as an index of effect size, but it is a measure of the
mean difference between two groups.
F-ratio
✓✓ Statistic calculated when using the analysis of variance
The eta coefficient would be used to
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
✓✓ a. estimate the strength of a nonlinear relationship
between two continuous variables.
The most common correlation coefficient
✓✓ Pearson r
Pearson r
✓✓ Used to measure the relationship between two continuous
variables that are related in a linear way
Note: eta is used when there is a nonlinear relationship
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Phi Coefficient
✓✓ Can be used to measure the correlation between two
dichotomous variables (i.e, variables that can take one of two
values)
Point-Bisceral Correlation
✓✓ Used to measure the correlation between a dichotomous
variable and a continuous variable.
Spearmena's rho
✓✓ Used to measure the correlation between two sets of
ranked data
You have conducted a study to assess the relationship between
salary and job performance, and you find a significant
correlation between these two variables. You assistant tells you
that the data fail to take into account a $25.00 cost of living
raise that every empoyee received. You should:
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.