Sep22 - Nonexperimental method Measure two variables to...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
9/22/10 1 Nonexperimental method Measure two variables to determine if they are related Also called “Correlational method” Cannot determine direction of cause and effect Third-variable problem (confounding variable): A third variable may cause the two that were measured Useful if we are interested in prediction Experimental method Manipulate one variable and measure effects on another - Establishes time order Eliminate effects of confounding variables: 1. Experimental control 2. Randomization Random number table Independent variable Manipulated variable in an experiment Sometimes called “predictor” in correlational studies Dependent variable Measured variable in an experiment Sometimes called “outcome variable” or “criterion” in correlational studies Three types of validity Construct validity – extent to which the operational definition reflects theoretical meaning of the variable Internal validity – extent to which we can conclude there is a causal relationship between variables Biggest threat: Plausible alternative
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 10/08/2010 for the course PSY 3001w taught by Professor Stellmack during the Fall '10 term at Minnesota.

Page1 / 3

Sep22 - Nonexperimental method Measure two variables to...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online