(a)   do not create levels of an independent variavle nor randomly assign subjects to these levels.

the degree to which a research design allows us to make causal statements between the independent and dependent variables.

(a)  

An internally valid experiment allows us to draw (a)  

An experiment has (a)   when we can demonstrate that only the antecedent conditions are responsible for group differences in behavior.

Laboratory experiments are often higher in (a)   validity because of their control of extraneous variables.

Researchers create levels of the IV and use procedures like (a)  

It is the generalizability or applicability to people and situations outside the research setting.

(a)  

(a)   studies are more frequently conducted in real-world settings with a more diverse sample of participants than experiments.

Experimental researchers have _____ external validity, some nonexperimental researchers have _____ internal validity.

(a)