Chapter One: What is Psychology?

Correlational Studies: Looking for Relationships

INTRODUCTION

Correlational studies look for relationships between variables.

WHAT'S AHEAD

• If two things are "negatively" correlated, like grades and TV watching, what's the relationship between them?
• If depression and illness are correlated, does that mean depression causes illness?

KEY CONCEPTS

Correlational Studies

---

Correlational Studies

INTRODUCTION

Correlation measures how strongly two variables are related to each other.

KEY CONCEPTS EXPLAINED

Positive Correlation - as values on one variable increase, the values on the other measure also increases.

Example - As height goes up, weight goes up.

Negative Correlation - as values of one variable increases, the value of the other decreases.

Example - The older the car, the lower the price. The more you watch tv, the lower your grades.)

Coefficient of Correlation - a number (the measure of correlation) that indicates the size and direction of the relationship between two variables.

Example:
A correlation of .15 suggests a weak relationship and .75 suggests a very strong relationship. A correlation of +.15 means it is a positive correlation and, -.75 indicates a negative correlation.

Correlation Equal Cause? Although a correlation indicates the size and direction of the relationship between variables, it does not indicate that one causes the other.

Example: The high positive correlation between storks nesting and the number of human births in European villages does not mean that storks bring babies.

GLOSSARY

		correlational study
		correlation
		variables
		positive correlation
		negative correlation
		coefficient of correlation

LINKS About Issues in Correlational Studies

• wwwlink: A discussion of "spurious"correlations.
• wwwlink: Examples of "spurious" correlations.

Reminder: Table 1.3 has a great summary comparing the advantages and disadvantages of all the research methods. Click on me to go to an interactive version of the table.

Next Topic - The Experiment: Hunting for Causes.........................Chapter Contents