example 1: page 161 #5 example 2: page 160 #1 explanatory variable - response variable - independent...
Post on 13-Jan-2016
226 Views
Preview:
TRANSCRIPT
Example 1: page 161 #5
Example 2: page 160 #1
Explanatory Variable -
Response Variable -
independent variable
dependent variable
Correlation coefficient - r
Measures the strength and direction of the linear relationship between quantitative variables.
Strength
+ r = positive correlation
- r = negative correlation
1 1r
Direction .8r
.5 .8r
.5r
strong
moderate
weak
1
1i i
x y
x x y yrn s s
Recipe for r
There is a _(strength)___, ___(direction)____, linear relationship between __(explanatory)__ and __(response)__.
Let’s use the formula to find r. This will be the only time we do it by hand. After today we will find it using on the calculator.
Posted speed limit (mph) Ave. # of weekly reported accidents
55 28
50 25
45 21
40 17
30 11
25 6
top related