Unit 1: Design & Analysis 2

Why do we conduct experiments?

To search for cause and effect.

What is the third variable problem?

When two variables appear to be correlated due to the influence of another variable.

Give an example of the third variable problem.

High ice cream sales and drowning rates, with summer acting as the third variable.

What is the directionality problem?

The uncertainty of whether variable A causes variable B or vice versa.

What are the three conditions to determine cause and effect?

1. Covariance Rule: variables must be related. 2. Temporal Precedence Rule: cause must occur before effect. 3. Internal Validity: ruling out other possible causal factors.

What is a quasi-experiment?

An experiment where the independent variable is not manipulated, often due to ethical concerns.

What are the key characteristics of experiments?

1. Used to determine causality. 2. Systematic study where researchers vary one or more factors (IVs) while holding other factors constant to control for confounding variables.