Transcript Analyzing Residuals Grade 9 Lesson 17 Learning Intentions › We are learning to analyze residuals.

Analyzing Residuals
Grade 9 Lesson 17
Learning Intentions
› We are learning to analyze residuals.
Success Criteria
› We are successful when we can...
– show a residual plot on a graphing calculator
for a set of data.
– use a residual plot to decide if a linear model
is appropriate for the data set.
Launch
y
x
What will the residual plot look
like?
y
x
Residual
Why is looking at the pattern in
the residual plot important?
0
x
Calculating Residuals and
Constructing a Residual Plot
Destination
Distance (miles)
Airfare ($)
Atlanta
576
178
Boston
370
138
Chicago
612
94
Dallas/Fort Worth
1216
278
Detroit
409
158
Denver
1502
258
Miami
946
198
New Orleans
998
188
New York
189
98
Orlando
787
179
Pittsburgh
210
138
St. Louis
737
98
Example 3
› On poster paper and using your group’s
data set:
– Create a scatter plot of the data.
– Find the least-squares regression line and
graph this line on your scatter plot.
– Create the residual plot.
› Be prepared to share your poster and
results with the class.
Questions to think about:
– Why is it important to look at the residual plot?
– Which data sets can be modeled well with
linear model and why?
– How can you tell if a linear model is a good
fit?
– Should any of these be modeled by something
other than a linear function? How can you tell?
Why is it important to
look at the residual
plot?
Lesson Summary
› After fitting a line, the residual plot can be
constructed using a graphing calculator.
› A pattern in the residual plot indicates that
the relationship in the original data set is
not linear.
Exit Ticket
› Please go to m.socrative.com
› Room number: 029102
› Suppose a scatter plot of bivariate
numerical data shows a linear pattern.
Describe what you think the residual plot
would look like. Explain why you think
this.
Learning Intentions
› We are learning to analyze residuals.
Success Criteria
› We are successful when we can...
– show a residual plot on a graphing calculator
for a set of data.
– use a residual plot to decide if a linear model
is appropriate for the data set.
Standards
CONTENT STANDARD
PRACTICE STANDARD
› S.ID-6b: Informally
assess the fit of a
function by plotting
and analyzing
residuals.
› MP4: Model with
mathematics. Students
use residuals and
residual plots to
assess if a linear
model is an
appropriate way to
summarize the
relationship between
two numerical
variables.