• NLREG has been selected as the "Editor"s Pick" by SoftSeek.

    link to

  • NLREG is in use at hundreds of universities, laboratories, and government agencies around the world (over 20 countries). For a list of a few organizations using NLREG click here.

  • If you have categorical variables, you may want to use a Decision Tree to model your data. Check out the DTREG Decision Tree Builder.

  • You also should check out the News Rover program that automatically scans Usenet newsgroups, downloads messages of interest to you, decodes binary file attachments, reconstructs files split across multiple messages, and eliminates spam and duplicate files.

    NIST Statistical Reference Datasets

    The Statistical Reference Datasets Project was developed by staff of the Statistical Engineering Division and the Mathematical and Computational Sciences Division within the Information Technology Laboratory of the National Institute of Standards and Technology.

    The NIST reference dataset suite contains 27 datasets for validating nonlinear least squares regression analysis software. NLREG has been used to analyze all of these datasets with the following results: NLREG was able to successfully solve 24 of the datasets, producing results that agree with the validated results within 5 or 6 significant digits. Three of the datasets (Gauss1, Gauss2 and Gauss3) did not converge, and NLREG stopped with the message "Singular convergence. Mutually dependent parameters?" The primary suggested starting values were used for all datasets except for MGH17, Lanczos2 and BoxBOD which did not converge with the primary suggested starting values but did converge with the secondary suggested starting values.

    In all cases where NLREG reported that it obtained a solution, the answers were correct.

    Results produced by NLREG when running each reference dataset can be viewed below. Note in the analysis listings that the background information about the dataset provided by NIST is listed first as an extended comment enclosed between '/*' and '*/' delimiters, the actual NLREG program (usually only a few lines) follows, and the output generated by NLREG is the final portion of the listing.

    Background Information

    Dataset Name
    Level of
    Number of
    Number of


    Misra1a Lower Exponential 2 14    Observed
    Chwirut2 Lower Exponential 3 54    Observed
    Chwirut1 Lower Exponential 3 214    Observed
    Lanczos3 Lower Exponential 6 24    Generated
    Gauss1 Lower Exponential 8 250    Generated
    Gauss2 Lower Exponential 8 250    Generated
    DanielWood Lower Miscellaneous 2 6    Observed
    Misra1b Lower Miscellaneous 2 14    Observed

    Kirby2 Average Rational 5 151    Observed
    Hahn1 Average Rational 7 236    Observed
    Nelson Average Exponential 3 128    Observed
    MGH17 Average Exponential 5 33    Generated
    Lanczos1 Average Exponential 6 24    Generated
    Lanczos2 Average Exponential 6 24    Generated
    Gauss3 Average Exponential 8 250    Generated
    Misra1c Average Miscellaneous 2 14    Observed
    Misra1d Average Miscellaneous 2 14    Observed
    Roszman1 Average Miscellaneous 4 25    Observed
    ENSO Average Miscellaneous 9 168    Observed

    MGH09 Higher Rational 4 11    Generated
    Thurber Higher Rational 7 37    Observed
    BoxBOD Higher Exponential 2 6    Observed
    Ratkowsky2 Higher Exponential 3 9    Observed
    MGH10 Higher Exponential 3 16    Generated
    Eckerle4 Higher Exponential 3 35    Observed
    Ratkowsky3 Higher Exponential 4 15    Observed
    Bennett5 Higher Miscellaneous 3 154    Observed

    Return to NLREG home page

    Download demonstration copy of NLREG.

    Download manuals for NLREG.

    Purchase NLREG.

    DTREG Decision Tree building software.