Statistics 12-5
8312STAT.DOC TI-83 international English Bob Fedorisko Revised: 02/19/01 12:42 PM Printed: 02/19/01 1:37
PM Page 5 of 38
The regression line appears to fit the central portion of the scatter plot well.
However, a residual plot may provide more information about this fit.
14.Press … 1 to select 1:Edit. The stat
list editor is displayed.
Press ~ and } to move the cursor onto
L3.
Press y [INS]. An unnamed column is
displayed in column 3; L3, L4, L5, and L6
shift right one column. The Name=
prompt is displayed in the entry line, and
alpha-lock is on.
15.Press y [LIST] to display the LIST
NAMES menu.
If necessary, press † to move the cursor
onto the list name RESID.
16.Press Í to select RESID and paste it
to the stat list editor’s Name= prompt.
17.Press Í. RESID is stored in column 3
of the stat list editor.
Press † repeatedly to examine the
residuals.
Notice that the first three residuals are negative. They correspond to the
shortest pendulum string lengths in L1. The next five residuals are positive, and
three of the last four are negative. The latter correspond to the longer string
lengths in L1. Plotting the residuals will show this pattern more clearly.