NORM_LNK(1)

NAME
norm_lnk - Normalization Program

SYNOPSIS
Calculates normalization parameters for classification data bases.

norm_lnk [ -pathdata directory ] [ -finput file ]
-fdescribe file [ -normalization n ] [ -fparam file ]
[ -debug n ] [ -verbose n ]

EXAMPLE
norm_lnk -pathdata $LNKHOME/data/class -finput vowel.train \
-fdescribe vowel.defaults -normalization 1 \
-fparam vowel.norm.simple

DESCRIPTION
LNKnet classification and clustering programs normalize input data using parameters calculated by the program norm_lnk. The normalization parameters for a data base are calculated based on the training data file and applied to all input patterns, training or testing, when they are read by a LNKnet program. Four types of normalization files are created by norm_lnk. They are described below. The type of file produced is specified by the normalization flag.

OPTIONS
-- Prints a list of all flags and arguments.

-pathdata directory
    The base directory used for finding the data files finput, and fdescribe and for storing the file fparam. A slash "/" is automatically added to the end of the base directory if it doesn't end with a slash.

-finput file
    The ASCII training file in pathdata with the data to be used for normalization. The format and naming conventions for input files are described on the classifier(1) manual page.

-fdescribe file
    This file contains settings for the data base type, the number of input features, labels for the input features, the number of output classes, and labels for the output classes. Description files are described on the classifier(1) manual page.

-fparam file
    Name of a file in pathdata for storing feature search results. This file is written using the routine norm_write_paramfile() found in nnlib.a. It can be read using norm_read_paramfile() or by using the parameter file handling routines in the library nnlib.a. In the LNKnet system, the normalization files are assumed to be named <base>.norm.<norm_type>. Where <base> is the name of the data base and <norm_type> describes which type of normalization parameters are in the file. The types are none, simple, pca, and lda. For example, the linear discriminant parameters for the vowel data base are stored in vowel.norm.lda.

-normalization n
    n determines which type of normalization file will be created.

    0 none
        Do not do normalization. Create a normalization file which, when applied, will result in the data being left alone.

    1 simple
        Calculate means and variances for each input dimension. When applied, the resulting input patterns have zero mean and unit variance in all dimensions. The default filename for a simple normalization parameter file is <base>.norm.simple. The simple normalization parameter file for the vowel data base is vowel.norm.simple.

    2 Principal Components Analysis
        PCA assumes that the entire feature set can be modeled as a multivariate Gaussian distribution. PCA finds a linear transformation that uncorrelates the features, or diagonalizes the covariance matrix. The first dimension in the transformed space corresponds to the direction in the original feature space with the greatest variance. The remaining dimensions are orthogonal to the first and correspond to directions of decreasing variance. The default filename for a principal components analysis normalization parameter file is <base>.norm.pca. The PCA normalization file for the vowel data base is vowel.norm.pca.

    3 Linear Discriminant Analysis
        LDA finds the linear transformation that maximizes a class separability criterion. LDA assumes that the classes and their means can be modeled by multivariate Gaussian distributions. The first dimension in the rotated space corresponds to the direction in the feature space along which the classes can be best separated. The remaining dimensions are orthogonal to the first and correspond to directions of decreasing separability of the classes. The default filename for a linear discriminant analysis normalization parameter file is <base>.norm.lda. The LDA normalization file for the vowel data base is vowel.norm.lda.

-debug n
    The value of n determines the quantity of status messages printed out while norm runs.

-verbose n
    The value of n determines the quantity of status messages printed out while norm runs.

REFERENCES
Charles R. Jankowski, Jr. A Comparison of Auditory Models for Automatic Speech Recognition Master's Thesis, Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, Cambridge, MA, May 1992. Pages 27-31.

SEE ALSO
classifier(1)

HISTORY
First written 24 June 1992 by Linda Kukolich

BUGS
Send bug reports to Linda Kukolich (kukolich@sst.ll.mit.edu)