Calculator User Manual

Chapter 20: A to Z Function and Instruction Reference
313
20ATOZ.DOC TI-86, Chap 20, US English Bob Fedorisko Revised: 02/13/01 2:42 PM Printed: 02/13/01 3:05 PM Page 313 of 11820ATOZ.DOC TI-86, Chap 20, US English Bob Fedorisko Revised: 02/13/01 2:42 PM Printed: 02/13/01 3:05 PM Page 313 of 118
LgstR
STAT CALC menu
Built-in equation variables
such as
y1
,
r1
, and
xt1
are
case-sensitive. Do not use
Y1
,
R1
, and
XT1
.
LgstR
returns a
tolMet
value that indicates if the
result meets the TI
-
86’s
internal tolerance.
•
If
tolMet
=
1
, the result is
within the internal
tolerance.
•
If
tolmet
=
0
, the result is
outside the internal
tolerance, although it
may be useful for general
purposes.
LgstR
[
iterations
,
]
xList
,
yList
,
frequencyList
,
equationVariable
Fits a logistic regression model (y=a/(1+be
cx
)+d) to real
data pairs in
xList
and
yList
and frequencies in
frequencyList
. The regression equation is stored to
equationVariable
, which must be a built-in equation
variable such as
y1
,
r1
, and
xt1
. The equation’s
coefficients always are stored as a list to built-in
variable
PRegC
.
The number of
iterations
is optional. If omitted, 64 is
the default. A large number of
iterations
may produce
more accurate results but may require longer
calculation times. A smaller number may produce less
accurate results but with shorter calculation times.
Values used for
xList
,
yList
, and
frequencyList
are
stored automatically to built-in variables
xStat
,
yStat
,
and
fStat
, respectively. The regression equation is
stored also to built-in equation variable
RegEq
.
In
Func
graphing mode:
{1,2,3,4,5,6}
¶
L1
b
{1 2 3 4 5 6}
{1,1.3,2.5,3.5,4.5,4.8}
¶
L2
b
{1 1.3 2.5 3.5 4.5 4…
LgstR L1,L2,y1
b
Plot1(1,L1,L2)
b
Done
ZData
b
LgstR
[
iterations
,
]
xList
,
yList
,
equationVariable
Uses frequencies of 1.
LgstR
[
iterations
,
]
xList
,
yList
,
frequencyList
Stores the regression equation to
RegEq
only.
LgstR
[
iterations
,
]
xList
,
yList
Uses frequencies of 1, and stores the regression
equation to
RegEq
only.