EXPERIMENT VS. CORRELATIONAL STUDY

EXPERIMENT

Researcher controls all conditionsExperimental group – 1 or more groups of

subjectsControl group – controlled condition where

participants may receive a placebo or no treatment at all (used as the standard for comparison)

ONLY EXPERIMENTATION IMPLIES CAUSATION

CORRELATION

Used when a controlled experiment can’t be doneCan NEVER be 100% sure groups are similar in

every way can NEVER say the condition was the cause of the effects you observed

DOES NOT IMPLY CAUSATIONCorrelation coefficient – set of scores to find the

closest correlation between 2 variables◦ Stronger relationship: 1.0

◦ weak relationship: 0.0Positive correlation – both variables increase

or decrease; negative correlation – one increases and the other decreases