PSYC 3300 Research Methods Exam 3 UPDATED ACTUAL
QUESTIONS AND CORRECT Answers
correlation coefficient r A single number, ranging from -1.0 to 1.0
indicates the strength and direction of an association between two variables
, bivariate correlation an association that involves exactly two variables
effect size the magnitude of a relationship between two or more variables
statistical significance a statistical statement of how likely it is that an obtained result occurred by
chance
replication repeating the essence of a research study, usually with different participants in
different situations, to evaluate external validity
outlier A value much greater or much less than the others in a data set
has a disproportionately large impact on the correlation coefficient
restriction of range in a bivariate correlation, the absence of a full range of possible scores on one
of the variables, so the relationship from the sample underestimates the true
correlation
curvilinear association as one variable increases, the level of the other variable increases and then
decreases (or vice versa)
ex: relationship between age and use of the healthcare system
directionality problem both variables are measured around the same time and it is unclear which
came first
third-variable problem an alternative explanation for variable association
ex: correlation between height and hair length (third variable is gender)
moderator a variable that changes the relationship between two other variables
ex: when measuring college student success, the moderator would be SSE
status
construct validity how well was each variable measured?
statistical validity how well does the data support the conclusion?
internal validity can we make a causal inference from an association?
external validity to whom can the association be generalized?
QUESTIONS AND CORRECT Answers
correlation coefficient r A single number, ranging from -1.0 to 1.0
indicates the strength and direction of an association between two variables
, bivariate correlation an association that involves exactly two variables
effect size the magnitude of a relationship between two or more variables
statistical significance a statistical statement of how likely it is that an obtained result occurred by
chance
replication repeating the essence of a research study, usually with different participants in
different situations, to evaluate external validity
outlier A value much greater or much less than the others in a data set
has a disproportionately large impact on the correlation coefficient
restriction of range in a bivariate correlation, the absence of a full range of possible scores on one
of the variables, so the relationship from the sample underestimates the true
correlation
curvilinear association as one variable increases, the level of the other variable increases and then
decreases (or vice versa)
ex: relationship between age and use of the healthcare system
directionality problem both variables are measured around the same time and it is unclear which
came first
third-variable problem an alternative explanation for variable association
ex: correlation between height and hair length (third variable is gender)
moderator a variable that changes the relationship between two other variables
ex: when measuring college student success, the moderator would be SSE
status
construct validity how well was each variable measured?
statistical validity how well does the data support the conclusion?
internal validity can we make a causal inference from an association?
external validity to whom can the association be generalized?
