Chapter 12: Statistics
203
ExpReg
[
Xlistname
,
Ylistname
,
freqlist
,
regequ
]
PwrReg—(ax
b
)
PwrReg
(power regression) fits the model equation y=ax
b
to the data using a least-squares fit and
transformed values ln(x) and ln(y). It displays values for
a
and
b
; when
DiagnosticOn
is set, it also
displays values for
r
2
and
r
.
PwrReg
[
Xlistname
,
Ylistname
,
freqlist
,
regequ
]
Logistic—c/(1+a
…
e
-bx
)
Logistic
fits the model equation y=c/(1+a
…
e
L
bx
) to the data using an iterative least-squares fit. It
displays values for
a
,
b
, and
c
.
Logistic
[
Xlistname
,
Ylistname
,
freqlist
,
regequ
]
SinReg—a sin(bx+c)+d
SinReg
(sinusoidal regression) fits the model equation y=a sin(bx+c)+d to the data using an
iterative least-squares fit. It displays values for
a
,
b
,
c
, and
d
. At least four data points are required.
At least two data points per cycle are required in order to avoid aliased frequency estimates.
