NLREG 6.2

NLREG 6.2 is a statistical analysis program used for operating linear and nonlinear regression analysis, surface and curve fitting, which calculates the values of parameters for an equation, whose form you specify, that cause the equation to best fit a set of data values.

NLREG can handle linear, polynomial, exponential, logistic, periodic, and general nonlinear functions. Unlike many "nonlinear" regression programs that can only handle a limited set of function forms, NLREG can handle essentially any function whose form you can specify algebraically.

NLREG features a full programming language with a syntax similar to C for specifying the function that is to be fitted to the data. This allows you to compute intermediate work variables, use conditionals, and even iterate in loops. With NLREG it is easy to construct piecewise functions that change form over different domains. Since the NLREG language includes arrays, you can even use tabular look-up methods to define the function. 

In addition to computing the optimal values of the parameters to best fit the function to the data, NLREG can generate plots of the data points and the fitted equation. In addition, it can plot the distribution of residual values and produce a normal probability plot. NLREG also computes auxiliary statistics such as Student"s t, Prob(t), F, Prob(F), Durbin-Watson, and, optionally, correlation and covariance matrices.

The Standard version of NLREG can fit up to 5 variables and parameters to the data observations. The Advanced version can handle up to 2000 variables and parameters. In addition, the Advanced version can generate 3D surface plots

In addition to performing classic nonlinear regression, NLREG can be used to find the root or minimum value of a general multivariate, nonlinear function. It can also be used in a special form where the independent variable is omitted; an interesting application of this is "circular regression" where a circle is fitted to a set of data points.

DLL (Dynamic Link Library) and COM object versions of NLREG are available for applications that want to call NLREG as an "engine" to perform regressions. Click here to see an example Visual Basic program that calls the NLREG COM Library. NLREG has been validated using the Statistical Reference Datasets developed by the National Institute of Standards and Technology. 

Major Features:

1. Perform linear and nonlinear regression analysis, surface and curve fitting
2. Decide the values of parameters for an equation
3. Able to handle linear, polynomial, exponential, logistic, periodic, and general nonlinear functions.
4. Include full programming language with a syntax similar to C for specifying the function fitted to the data.
5. Make it easy to construct piecewise functions that change form over different domains.
6. NLREG language includes arrays letting you to use tabular look-up methods to define the function. 
7. Able to generate plots of the data points and the fitted equation. In addition, it can plot the distribution of residual values and produce a normal probability plot.
8. Compute auxiliary statistics such as Student"s t, Prob(t), F, Prob(F), Durbin-Watson, and, optionally, correlation and covariance matrices.
9. Used to find the root or minimum value of a general multivariate, nonlinear function.
10. Used in a special form where the independent variable is omitted
11. DLL (Dynamic Link Library) and COM object versions of NLREG available
12. NLREG has been validated using the Statistical Reference Datasets

• Addition of function to compute integrals.
  

Requirements:

• Windows system
• 256 MB of RAM
• 5 MB of disk space