Chapter 8 Flashcards
variables in bivariate correlation can be ____ or ____
quantitative or categorical
when to use scatterplot in bivariate corr and how can u describe the relationship seen?
if both variables r quantitative
use correlation coefficient r
when to use bar graph in bivariate corr and how can u describe the relationship seen?
if one variable is categorical
use difference between two group means
in bivariate correlational study, since they have 2 _____variables, ______of each measure must be interrogated
measured
construct validity
what are the 6 areas of interest to interrogate statistical validity of association claims
Effect size (strength of “r”)
Precision (confidence interval of “r”)
Replication of the study
Outliers
Restriction of range
Whether association is curvilinear
CORRPE
do correlational studies satisfy all 3 criteria for causal claim?
NO
May show covariance
Dont usually satisfy temporal precedence
Cannot establish internal validity
can bivariate correlations be moderated?
yes
bivariate corr
association that involves exactly 2 variables
Restriction of range
in bivariate correlation this is 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
association that is not a straight line.
Directionality problem
when both variables are measured at the same time so its unclear which variable in the association came first (related to temporal precedence)
Third variable problem
existence of possible alternative explanation for the association between 2 variables (kinda like confound)
Spurious association
bivariate association attributable to systematic mean diffs on subgroups in the sample (original association is not present in the subgroups)
moderator
variable that changes relationship between 2 other variables depending on its level
