List I
Methods of research
List II
Features emphasized
(A)
Experimental
(I)
Primary and secondary sources tapped with emphasis on internal criticism
(B)
ExPost Facto
(II)
Status of facts and conditions are ascertained
(C)
Descriptive
(III)
A variable is manipulated to see its effect on other variable
(D)
Historical
(IV)
The differences are noted and facts causal or otherwise are determined