STUDY GUIDE - unit 3

# STUDY GUIDE - unit 3 - Study Guide Unit 3 -DEFINITIONS: 1....

This preview shows pages 1–3. Sign up to view the full content.

Study Guide – Unit 3 - DEFINITIONS: 1. Covary - to what extent the scores of one variable are reliably related to those of another variable 2. Correlation - Relationship between 2 variables. 3. Correlational research - the process researchers use to determine whether 2 or more naturally occurring variables are related 3. Correlation coefficient - number that indicates to what degree 2 variables are related in a linear fashion 4. Coefficient of determination - indicates the proportion of systematic variance in one variable that can be accounted for by the other variable 5. Restriction of range 6. Online outlier - Scores that deviate obviously from the rest of the data; can make the correlation seem stronger than it should be 7. Offline outlier - Scores that deviate obviously from the rest of the data; can make the correlation seem weaker than it should be 8. Directionality problem - does variable A cause variable B, or does variable B cause variable A? 9. Third variable problem - an extraneous variable may account for the correlation between 2 variables 10. Partial correlation - allow us to examine the correlation between 2 variables when the influence of a 3 rd variable is removed. Correlation coefficients : -When do you use Pearson’s r? - The most common correlation coefficient Ranges from -1.0 to +1.0 Need to interpret the sign and the magnitude of the number Only use with continuous variables! -When do you use phi? -Phi: used when both variables are categorical -When do you use spearman’s rho? - used when both variables are ordinal -When do you use point biserial? - used when one variable is continuous and one is categorical -Know the 2 things you look at to interpret a correlation coefficient 1) Sign “+” means a direct, positive relationship “-” means an inverse, negative relationship 2) Magnitude The size of the number tells you how strong the correlation is. -What we conclude if there’s a significantly large correlation between 2 variables; what we conclude if there’s not a significantly large correlation between 2 variables

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

View Full Document
- What are the factors that affect correlations (SIGNIFICANCE?), and how does each factor affect it? 1) Sample Size
This is the end of the preview. Sign up to access the rest of the document.

## This note was uploaded on 04/17/2008 for the course DEP 3103 taught by Professor Lane during the Spring '08 term at FSU.

### Page1 / 5

STUDY GUIDE - unit 3 - Study Guide Unit 3 -DEFINITIONS: 1....

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online