ch8 bivariate correlations research methods

what is a bivariate correlation/association

an association that involves exactly two variables

when it comes to interrogating association claims, what is construct validity asking

how well was each variable measured and whether the measures accurately reflect the concepts they are intended to represent

when it comes to interrogating association claims, what is statistical validity asking

how well does the data support the conclusion

what two validities are important for association claims 

construct validity and statistical validity

what is internal validity asking for association claims

can we make a causal inference from an association

what if effect size

describes the strength of an association between two or more variables

when p <.05, it is statistically significant, what else does this mean about the result 

when it is unlikely the result came from the null hypothesis population

what is replication 

the process of conducting a study again to test whether the result is consistent 

what is an outlier

an extremely deviant individual, score that stands out as either much higher or much lower than most of the other scores in a sample

what is 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

what is a curvilinear association

an association between two variables that is not a straight line, instead, as one of the variables increases, the level of the variables increases and then decreases (or vice versa)

what is covariance 

a statistical measure that indicates how two variables change together 

what does applying the three causal criteria mean

applying covariance, temporal precedence, and internal validity (third-variable problem)

what is directionality problem

in a correlational study, the occurence of both variabales being measured around the same time, making it unclear which variable in the association came first

what is a correlational study

measures two or more variables to determine the statistical relationship between them without manipulating either

what is reverse causation 

in a study that finds the relationship between variables A and B, the plausible inference that either A could cause B or that B could cause A 

what is third variable problem

in a correlational study, the existence of a plausible alternative explanation for the association between two variables

what is a spurious association

a bivariate association that is attributable only to systematic mean differences on subgroups within the sample; the original association is not present within the subgroups

what is a moderator

a variable that, depending on its level, changes the relationship between two other variables

ex- gender identity can moderate the relationship between years of experience and salary, as the relationship may differ for men, women, and other gender identities