1. Correlation Coefficient (r)
r > 0.8 Strong positive linear relationship
0.8 < r < 0.5 Moderate positive linear relationship
0.5 < r < 0.2 Weak positive linear relationship
Correlation Coefficient (r)

2. Correlation Coefficient
0.2 < r < -0.2 No linear relationship
-0.2 < r < Weak negative linear relationship
-0.5 < r < Moderate negative linear relationship
-0.7 < r < Strong negative linear relationship
Correlation Coefficient

3. Correlation Coefficient
Using calculator
Stat menu
Enter data in list
Calc
Reg X
r =
Correlation Coefficient

4. Correlation Coefficientx 2 3 4 6 8 9 10 y 20 18 17 16 14 12 11 x 2 4 5 7 9 10 11 15 y 3 6
Correlation Coefficient

5. r =
r =

6. Question 1, page 580
Question

7. Product Moment Correlation Coefficient
r = Sxy/SxSy
Sxy is called the covarience of x and y
Sx is the standard deviation of x
Sy is the standard deviation of y
Product Moment Correlation Coefficient

9. Line of best fit The “by eye” method Using the locus of means
Method of least squares (linreg- calculator
Line of best fit

10. Finding the line of best fitx 2 4 5 7 9 10 11 15 y 3 6
Finding the line of best fit