Example 2. Find the
other "Least Squares Lines"
for
the data points
.
Use the subroutine Regression to find the line.
2 (a). Use the
computer to find the least squares lines
.
2 (b). Is it the same
as the line we found in Example 1 ? Why?
Solution 2.
First, enter the data points.
Reverse the order of the coordinates of the points
from
to
.
Use Mathematica to find the "Least Squares
Line"
.
Plot the "Least Squares Line"
using
the ParametricPlot procedure.
![[Graphics:../Images/LeastSqLineMod_gr_78.gif]](../Images/LeastSqLineMod_gr_78.gif)
Compare the two "Least Squares Lines"
.
![[Graphics:../Images/LeastSqLineMod_gr_84.gif]](../Images/LeastSqLineMod_gr_84.gif)
Are the two lines the same ? Solve the second formula for x in terms of y.
The two formulas are not the same.
The sum of the residual's squared for this example is:
Which can be compared with example 1.
Which "least squares fit" do you think is best ?
Question. Are we comparing the "same thing" or is it apple's verses oranges?
(c) John H. Mathews 2004