Texas Instruments TI-84 Plus Manual Book page 284

The new residual plot shows that the residuals are random in sign, with the residuals
increasing in magnitude as the string length increases.
To see the magnitudes of the residuals, continue with these steps.
29. Press r.
Press ~ and | to trace the data. Observe the
values for Y at each point.
With this model, the largest positive residual is
about 0.041 and the smallest negative residual is
about L0.027. All other residuals are less than 0.02
in magnitude.
Now that you have a good model for the relationship between length and period, you can
use the model to predict the period for a given string length. To predict the periods for a
pendulum with string lengths of 20 cm and 50 cm, continue with these steps.
30. Press  ~
secondary menu, and then press
FUNCTION
select .
1:Y1 Y1
Chapter 12: Statistics
to display the
1 VARS Y-VARS
is pasted to the home screen.
to
1
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