Ch. 8 Flashcards
What is a bivariate correlation?
associations that involve exactly two variables (quantitative variables or categorical data)
What is a curvilinear association?
An association between two variables which is not a straight line; instead, as one variable increases, the level of the other variable increases and then decreases (or vice versa)
What is a directionality problem?
In a correlational study, the occurrence of both variables being measured around the same time, making it unclear which variable in the association came first
What is the effect size?
The magnitude, or strength, of a relationship between two or more variables
What is the mean?
An arithmetic average; a measure of central tendency computed from the sum of all the scores in a set of data, divided by the total number of scores
What is a moderator?
a variable that, depending on its level, changes the relationship between two other variables
What is an outlier?
A score that stands out as either much higher or much lower than most of the other scores in a sample
What is replication?
The process of conducting a study again to test whether the result is consistent
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 Statistical significance?
In NHST< the conclusion assigned when p<.05; that is, when it is unlikely the result came from the null-hypothesis population (unlikely it occurred due to chance)
What is 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 third-variable problem?
In a correlational study, the existence of a plausible alternative explanation for the association between two variables
