Texas Instruments TI-82 Manual page 25

Press
STAT 1
in list L .
1
The first differences in L
Ònearly constantÓ. A linear model might be a good
fit to the data.
¥ Program DIFF should not be used for data with input (L
spaced. First differences give no information about a possible linear fit to data with
inputs that are not the same distance apart. If you try to use program DIFF with input
data that are not evenly spaced, the message INPUT VALUES NOT EVENLY SPACED
appears and the program stops.
TI-83 If you do not want to use program DIFF, you can
use your TI-83 to compute first differences of any list.
Press
2nd STAT
Error!
Use to scroll to the right to see the remainder of
the first differences. Use
1.4.7 FINDING A LINEAR MODEL
best fits the data. Your calculator can find two different, but equivalent, forms of the linear
model: y = ax + b or y = a + bx . For convenience, we always choose the model y = ax + b.
TI-82 Press
STAT
.
ENTER
Note: If you receive an error message, reset the statistical
setup to that indicated on page A-1 of this Guide.
The linear model of best fit for the aligned tax data
entered in Section 1.4.4 of this Guide is displayed on
the home screen.
(The r that is shown is called the correlation coefficient.
It is something you will learn about in a statistics course
and should be ignored in this course.)
Copyright © Houghton Mifflin Company. All rights reserved.
( ) to view the first differences
EDIT
are not constant, but are
3
( ) ( )
LIST OPS
to scroll back to the left.
Use your calculator to obtain the linear model t h a t
( ) (
CALC 5 LinReg(ax+b)
) values that are not evenly
1
)
A-25
Chapter 1