Basic HTML Version
© 2014 Pacific Crest
337
Step
Explanation
2. Plot the points
Create a visual plot of the points (scatter plot) to investigate.
1. Is the relationship linear (if not, stop)
2. Predict a slope
3. Predict the y-intercept
4. Create the approximate linear equation
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Test
Quiz
1.
Is the relationship linear? YES
2.
Predict a slope
Draw a line through the two points that are closest to the expected line. The
points are ordered pairs (3, 43) and (20, 93). Calculate the slope of the line
between these two points:
(
)
(
)
−
=
=
−
93 43 50
20 3 17
m
3.
Predict the y-intercept: 34
4.
Create the approximate linear equation (use the point-slope formula)
(
)
(
)
− =
−
= − +
≈ −
50 43
3
17
50 150 43
17 17
3 34
y
x
y
x
y x
3.
Calculate the
statistics
For each variable in the simple linear regression, calculate its mean and
standard deviation
quiz
test
mean
10.7647
72.9412
standard deviation
5.517
14.981
7.4 Simple Linear Regression