Understand how we can test and improve validity of a study The Pros and Cons of different sampling techniques

Definitions Internal – Are we really measuring what we want to Popluation – Can we apply our findings to other populations other than our sample Ecological – Does it reflect real life External – Does the task reflect real life?

Confounding Variables – uncontrolled Extraneous variables Extraneous Variables – extra variables that can be controlled Demand Characteristics – when a pps guesses the aim of the study and behaves in a way they think is expected Experimenter Bias – when a psychologist designs their method or observation in a way that biases their results towards their hypothesis Definitions

IV DV Confounding variable Extraneous Variables

ALL these things affect VALIDITY!!

Improving External Validity - Repeat the experiment in different ways Context Validity/Ecological Validity Also applies across different contexts Temporal/Historical Validity Do findings from the past still apply? Population Validity Can we apply our findings to other populations (not just our sample)

Improving Internal Validity 30 word wonder! Face validity Content Validity Concurrent Validity Predictive Validity Write it on the board!