Survey research and design in psychology/Lectures/Correlation

Lecture 4: Correlation

Resource type: this resource contains a lecture or lecture notes.

This is the fourth lecture for the Survey research and design in psychology unit of study.

Outline

This lecture overviews non-parametric and parametric approaches to (bivariate) measures of association (dependence), i.e., correlational statistics and graphing. The lecture is accompanied by a computer-based tutorial.

This lecture explains:

1. The purpose of correlation (what types of question(s) are we trying to answer?)
2. Nature of covariation (what does it mean if two variables covary or “vary together”?)
3. Correlational analyses
   1. Types of answers – What can we conclude?
   2. Types of correlation – Selecting appropriate correlations and graphs based on the variables' level of measurement
   3. Interpretation – of correlational relations and graphs
4. Assumptions and Limitations
5. Dealing with several correlations

Slides

• Lecture slides (Google Slides]
• 2018 handouts:
  • Download 6 slides to a page:
  • Download 3 slides to a page:

Readings

1. Howitt and Cramer (2014a):
   1. Chapter 07: Relationships between two or more variables: Diagrams and tables (pp. 86-97
   2. Chapter 08: Correlation coefficients: Pearson correlation and Spearman’s rho (pp. 98-119)
   3. Chapter 11: Statistical significance for the correlation coefficient: A practical introduction to statistical inference (pp. 143-156)
   4. Chapter 15: Chi-square: Differences between samples of frequency data (pp. 196-217)

See also

• Descriptives & graphing (Previous lecture)
• Exploratory factor analysis (Next lecture)
• Correlation (Tutorial)
• Correlation
• Correlation quiz (Practice)

External links

• Relationships between two or more variables: Diagrams (Ch 9) Quiz (Practice) (Howitt & Cramer, 2014)
• Correlation co-efficients (Ch 10) Quiz (Practice) (Howitt & Cramer, 2014)