======================
RegrePsion version 1.0 
======================
Freeware for Psion Series 3mx/3c/3a
19.07.1999


Files:
readme.txt	This file
regrepsi.opa	Application file
regr.pic	Icon file


Installation:
=============
Copy regrepsi.opa file to your APP directory. Create \APP\REG directory
and copy the icon file Stat.pic to this directory.

\APP\regrepsi.opa
\APP\REG\regr.pic

Install RegrePsion from System screen ->App->Install

Note! Data files are saved to \OPD directory


What is RegrePsion?
===================
I have a need to analyze numerical data quite often (averages, RSD, correlation...). I found
only few programs for my purposes and they are sharewares and didn't even include the
basic properties I needed. So I decided to make my own one.

RegrePsion is quite simple but efficient freeware tool for people who needs to analyze
data e.g. averages, sum, std, regression, correlation, extra/interpolation...

Overview:
- Max number of datapoints (x,y) is 50. Data can be saved/loaded.
- Units of X and Y can be defined
- Sum, Max and Min of the data
- Average, Std, RSD and Variance of the data
- Transformation of X or/and Y: ln(), log(), exp(), reciprocals
- Regression
	- Curve types: Linear, Geometric (=Power), Exponenetial
	- Correlation coefficients
	- Residuals, residual statistics: # of resid. >0, # of resid.<0,
	  Calculated values (=fitted y values)
	- Extra / Interpolation
- Number of decimals (can be defined between 1-10)


Menu:
=====
File
Open	- Open a saved data file
Save as	- Save a data file (name max. 8 characters)
Exit	- Exit RegrePsion

Data
Input   - Input your datapoints, max 50 datapairs
Edit	- Edit your datapoints
View	- Show your current datapoints
Units	- Define units to X and Y
Transform - Transform X or Y (ln, log, exp, 1/v). If you choose e.g. X and ln(), program
will calculate ln(x1), ln(x2), ln(x3)... and use these values in your regression, averages
and so on (there is no undo). You can see new values from View.

Stat
Sum   - Calculates Sum of your data and Min and Max values of the data.
Average, Std - Calculate Average, Variance, Standard deviation and RSD of your data.
Regression - Make a linear, geometric (power) or exponential regression and calculate
a correlation coefficient. After having a curve parameters you can also extrapolate 
or watch residuals.
(equations: linear y=a+b*x, power y=a*x to power y, exponential y=a*exp(b*x)).
Residuals = The difference betweem the predicted and observed values (y(calculated)-y).
These are unweighted residuals.

Info
Preferences - Set number of decimals (1-10), default is 5.
Help - ?
About - About RegrePsion


Getting started:
================
In main screen there is text 'Current Data:' where you can see the filename
of the current opened data. If you have not saved your data there is no any
name in the screen.

Enter number of your datapoints (Data -> New). Max 50 pcs. (x,y)
Enter X and Y:s -> x1, y1, x2, y2,... (one point at time)
After last point you can check your data from Data -> View
If you have made mistakes you can edit your data from Data -> Edit

Define your units from Data -> Units e.g. x: mg/ml y:abs.
It helps you to identify your data in later stages (extrapolation, regression). 

In many cases it's possible to linearize your data by transforming it. You can
make the most common transforms from Data -> Transform (ln(), log(), exp(), 1/x or 1/y)

Regression: (Linear was first used to examine the relationship between the heights of
fathers and sons)
Go to Stat -> Regression. Select your curve type: linear, geometric (=power), exponential.
-> In the first dialog you can see the fitted curve equation, values of calculated
parameters and correlation coefficient (r). Correlation coefficient is calculated from
Pearson equation and it ranges from -1 to +1. If r is 0 there is no correlation at all.
If r=1 there is perfect positive correlation (both always increasing together) and if
r=-1 there is perfect negative correlation (one always decreasing as the other increases).

After dialog you will see the menu where you can choose Extrapolation, Residuals or Exit.
Extrapolation (/interpolation) will calculate your Y according to fitted curve equation
and entered X value.
Residuals: Shows residuals from the current regression.
Exit will return you to main menu. 


Future plans:
=============
Polynomial regression, plots, Export/Import, print...
(version 1.1 coming soon)

I'm not giving any guarantee about calculated results. I have made my own tests and it
seems to give good (correct) results in any cases. 

If you found any errors or want to develope this program, please let me know! or send
me a postcard anyway

Juha Hinkula
Sahatie 3 D 34
FIN-01650, Vantaa
Finland
Tel. +358-40-5178472