We very often set the cutoff for a significant p value at 0.05, and minimal acceptable power at 0.8. Sometimes p of 0.01 is demanded. Sometimes power of 0.90 is demanded. But what are these values and how are they chosen? Read more!
Two terms that are frequently confused are moderation and mediation:
Definitions of moderating and mediating:
A mediating variable is one that accounts for or alters another relationship. A strict definition is that the mediating variable has to greatly reduce or even eliminate the relationship. A more lenient definition is that it affects the relationship. I favor that more lenient definition. A moderating variable is one that interacts with a variable. An interaction means that the relationship between one independent variable (IV) and the dependent variable (DV) is different at different levels of the other IV. Read more!
Regression is a set of statistical techniques for relating a dependent variable to one or more independent variables. Briefly, a dependent variable (sometimes called an outcome variable) is one that you think is related to the independent variables. Although regression can’t prove causation, you usually think that the relationship goes from the independent variable(s) and to the dependent variable. (I will discuss the distinction in another post).
What are sensitivity and specificity?
Sensitivity and specificity are measures of the effectiveness of a diagnostic test. Most often they are used as part of medical research when doctors (or others) try to determine if a patient has a disease or not. This leads to four possible results: Read more!