Texas Instruments TI-80 Calculator User Manual


 
Statistics 9-7
Plot the residuals, and predict how many buildings of 12 or more stories there
are in a city with a population of 300 thousand.
27. Press
(
6
¸
to turn off
Y1
.
28. Press
)
, and change the Window variable
values to best show the residuals. Use the minimum
and maximum values of
L4
(
M
10.31862745 and
10.74019608) as guidelines for setting
YMIN
and
YMAX
.
29. Press
,
to plot the residuals.
+ marks each residual value.
30. Press
y
ã
QUIT
ä
M
to return to a clear Home
screen. Press
y
ã
Y-VARS
ä
1
to select
Y1
. Then
press
£
300
d
Í
.
The value of
Y1
(the linear regression equation) for
X
=300 (which represents 300 thousand city
population) is shown. Remember to round the
number mentally to an integer (13) to represent
whole buildings.