EqFit Overview --

The best way to summarize a mass of numerical data is to use a simple equation. To develop that equation, you need graphical and equation fitting tools. EqFit gives you these tools to build and test trial equations against your data using standard calculation methods from the Statistics field.

The Statistics menu provides two methods to fit equations to data. Use the Regression Workbench menu to perform Multiple Linear Regression with up to ten dependent variables. You can build hundreds of different equations in the Workbench by transforming individual variables in ten different ways. For example, in Chemistry, the equation for vapor pressure is well known and can be readily built in the Workbench. A chemist with vapor pressure vs. temperature data for a compound can find the equation constants by fitting the data to the known equation set up in the Workbench. Use the Simple (XY) Regression menu to perform Simple Linear Regression to fit equations with only one dependent variable. You can try any of twelve equations to automatically obtain the best equation fit. You can monitor the equation fitting progress by using the Graphs menu to plot any of several variables such as residuals vs. any data column.

Use the Statistics/Regression Reports menu to place the equation fitting results in the Results window at any time after a calculation. From this window, you can edit, print, or save the reports to a file.

EqFit receives data by opening a text file, entering data from the keyboard into a grid, or downloading from the Clipboard into a grid. The first option is available from the File/Open Data menu and the last two are available from the File/New Data menu. Select the Edit/Input Data menu to change, delete, or add to the data currently in EqFit.

The EqFit tools allow you to apply your statistical know how to practical problems with a minimum of effort. Regression benchmarks that you can run are included to satisfy quality concerns.