37 lines
1.1 KiB
JavaScript
37 lines
1.1 KiB
JavaScript
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var vows = require('vows');
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var assert = require('assert');
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var suite = vows.describe('jStat.skewness');
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require('../env.js');
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suite.addBatch({
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'skewness': {
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'topic': function() {
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return jStat;
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},
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'returns accurate skewness value': function(jStat) {
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// from normal distribution in R: > rnorm(12); skewness(set) => -0.03270
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var set =
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[-0.28157961, -0.75577350, 0.61554139, 0.26864022, -0.42703435,
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-0.99927791, -0.07113527, -1.39327183, 0.34871138, 1.17909042,
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-0.22951562, 0.22341714];
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var skew = jStat.skewness(set);
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assert.isTrue(skew > -0.03271);
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assert.isTrue(skew < -0.03269);
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},
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'skewness from instance': function(jStat) {
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var set =
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[-0.28157961, -0.75577350, 0.61554139, 0.26864022, -0.42703435,
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-0.99927791, -0.07113527, -1.39327183, 0.34871138, 1.17909042,
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-0.22951562, 0.22341714];
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var skew = jStat(set).skewness();
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assert.isTrue(skew > -0.03271);
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assert.isTrue(skew < -0.03269);
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}
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}
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});
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suite.export(module);
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