Texas Instruments TI-83 PLUS - Manual (Page 362)

TI-83 Plus Statistics 359
LinReg (ax+b)
LinReg(ax+b) (linear regression) fits the model equation y=ax+b to the data
using a least-squares fit. It displays values for a (slope) and b (y-intercept);
when DiagnosticOn is set, it also displays values for r 2 and r .
LinReg(ax+b) [ Xlistname , Ylistname , freqlist , regequ ]
QuadReg (ax 2 +bx+c)
QuadReg (quadratic regression) fits the second-degree polynomial
y=ax 2 +bx+c to the data. It displays values for a , b , and c ; when
DiagnosticOn is set, it also displays a value for R
2 . For three data points,
the equation is a polynomial fit; for four or more, it is a polynomial
regression. At least three data points are required.
QuadReg [ Xlistname , Ylistname , freqlist , regequ ]
CubicReg—(ax 3 +bx 2 +cx+d)
CubicReg (cubic regression) fits the third-degree polynomial
y=ax 3 +bx 2 +cx+d to the data. It displays values for a , b , c , and d ; when
DiagnosticOn is set, it also displays a value for R
2 . For four points, the
equation is a polynomial fit; for five or more, it is a polynomial regression.
At least four points are required.