Saturday, June 3, 2017

HP 20S and HP 21S: Simple Logistic Regression

HP 20S and HP 21S:  Simple Logistic Regression

For the HP Prime and TI-84 Plus CE versions, please click here:  http://edspi31415.blogspot.com/2017/04/hp-prime-and-ti-84-plus-ce-simple.html

This program attempts to fit a simple logistic curve of data (X, Y) to the equation:

y = 1/(A + B*e^(-x))

By the following transformations:

X’ = e^(-X)  
Y’ = 1/Y

And performing linear regression analysis on X’ and Y’.   Note that the data point which includes Y = 0 is not allowed. 

The keystrokes for the HP 20S and HP 21S are slightly different.  Each program will be shown separately.

Input:
Initialize the data:  XEQ A
For each data point:  x, [INPUT], y, XEQ B
Calculate the parameters:  XEQ C.  B is shown first, then A.

HP 20S Program: Simple Logistic Regression

STEP
CODE
KEY
01
61, 41, A
LBL A
02
61, 75
CLRΣ
03
61, 26
RTN
04
61, 41, B
LBL B
05
15
1/X
06
51, 31
SWAP
07
32
+/-
08
12
e^x
09
51, 31
SWAP
10
16
Σ+
11
61, 26
RTN
12
61, 41, C
LBL C
13
61, 16
m, b
14
26
R/S
15
51, 31
SWAP
16
61, 26
RTN

HP 21S Program: Simple Logistic Regression


STEP
CODE
KEY
01
61, 41, A
LBL A
02
61, 75
CLRΣ
03
61, 26
RTN
04
61, 41, B
LBL B
05
15
1/X
06
51, 31
SWAP
07
32
+/-
08
12
e^x
09
51, 31
SWAP
10
16
Σ+
11
61, 26
RTN
12
61, 41, C
LBL C
13
51, 14
m, b
14
26
R/S
15
51, 31
SWAP
16
61, 26
RTN

Like the last post (minimum and maximum), this is one of my favorite programs I have done this year.  I think the Wheatstone circuit would also make the list.

Eddie


This blog is property of Edward Shore, 2017

No comments:

Post a Comment

HHC 2017 In Review

HHC 2017 In Review Hello Nashville, TN! HHC 2017 took place on September 16 and 17, 2017 in Brentwood, TN.  If you have not go...