Flashcards in Week 10 Lecture Deck (6)
Why is variance necessary in research?
Without variance, there is nothing to test.
Why do research designs control unwanted sources of variance?
In order to evaluate the effects of the independent variable.
How do we maximise experimental variance?
Make sure that there are real differences between the groups (using a manipulation check).
How do we control extraneous variance?
Make sure the groups are as similar as possible at the start of the study.
How do we minimise error variance?
Control with careful measurement or with special designs (e.g., correlated-group designs).