Texas Instruments TI-83 PLUS - Manual (Page 357)

TI-83 Plus Statistics 354
Diagnostics Display Mode
When you execute some regression models, the TI-83 Plus computes
and stores diagnostics values for r (correlation coefficient) and r
2
(coefficient of determination) or for R
2 (coefficient of determination).
r and r
2 are computed and stored for these regression models.
LinReg(ax+b) LnReg PwrReg
LinReg(a+bx) ExpReg
R
2 is computed and stored for these regression models.
QuadReg CubicReg QuartReg
The r and r
2 that are computed for LnReg , ExpReg , and PwrReg are
based on the linearly transformed data. For example, for ExpReg
(y=ab^x), r and r
2 are computed on ln y=ln a+x(ln b).
By default, these values are not displayed with the results of a
regression model when you execute it. However, you can set the
diagnostics display mode by executing the
DiagnosticOn or DiagnosticOff
instruction. Each instruction is in the
CATALOG
(Chapter 15).