Page 120 - Quantitative Data Analysis

Quantitative Data Analysis
Simply Explained Using SPSS

Notation:

– Sample: r
– Population: ρ

Example:
1. What is the relationship between school attendance and
school grades for high school seniors?

2. What is the relationship between GRE scores and grad
school GPA of students in Special Education?

Direction of Correlation

1. If high scores on one variable correspond to high scores on
another variable, and low scores on the variables also
correspond; the relationship is said to be positive.

2. Conversely, if high scores on one variable correspond to low
scores on another variable, and vice versa; the relationship
is said to be negative

3. Correlation coefficients can be any value between -1.00 and
1.00.
Examples

1. Cigarettes smoked per day and lung capacity

2. Hours of driving and number of accidents

Scatter Plots and Types of Correlation

The Theory and Applications of Statistical Inferences 104