manipulation
Question
The main difference between manipulation of an independent variable and observation of naturally occurring
variations in an independent variable is that
| naturally occurring variations provide more persuasive evidence of a causal relationship involving the independent variable. |
| manipulation provides more persuasive evidence of a causal relationship involving the independent variable. |
| manipulation is typically done in artificial laboratory settings, whereas observation of naturally occurring variations can be done in schools. |
| manipulation requires the involvement of fewer research participants than observation of naturally occurring variations. |