User Manual

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.