Research issues

What are extraneous variables

Variables that aren’t the IV that affects the DV

They are irrelevant variables

E.g. lighting in a lab, age of participants

What is a confounding variable

Kind of EV but systematically changes with IV

Makes it hard to tell if ch age in Dv was due to IV or confounding variable

What are investigator effects

Effect of investigators behaviour on research outcome (DV)

What is randomisation

Use of chance to reduce effects of bias when deciding experiments, conditions

E.g. deciding order of conditions, selection of participants

What is standardisation

Using exact same formalised procedures and instructions for every participant in the research.

Eliminates any non standardised instructions as being extraneous variables