nlp-toolkit/lib/crossValidation.js

This module covers some basic nlp principles and implementations. Every implementation in this module is written as stream to only hold that data in memory that is currently processed at any step.

/**
 * Module to validate classifiers via cross validation.
 */


'use strict';


/**
 * MODULES.
 */
var through2 = require('through2');
var validateClassifier = require('./validateClassifier.js');


/**
 * FUNCTIONS.
 */
function crossValidation(options) {
  options = options || {};
  var classifiers = options.classifiers || [];
  classifiers = [].concat(classifiers);
  var results = [];
  return through2.obj(function (chunk, enc, callback) {
    results = classifiers.map(function (classifier) {
      return chunk.map(function (el, index) {
        var testData = [].concat.apply([], chunk.slice(index, index+1));
        var trainingData = [].concat.apply([], chunk.slice(0, index).concat(chunk.slice(index+1)));
        return validateClassifier({
          testSet: testData,
          trainingSet: trainingData,
          classifier: classifier
        });
      });
    });
    return callback();
  }, function (callback) {
    this.push(results);
    return callback();
  });
}


/**
 * EXPORTS.
 */
module.exports = crossValidation;