105 lines
2.4 KiB
Plaintext
105 lines
2.4 KiB
Plaintext
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{{alias}}( x, y[, options] )
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Computes a two-sample F-test for equal variances.
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The returned object comes with a `.print()` method which when invoked will
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print a formatted output of the results of the hypothesis test.
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Parameters
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----------
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x: Array<number>
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First data array.
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y: Array<number>
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Second data array.
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options: Object (optional)
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Options.
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options.alpha: number (optional)
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Number in the interval `[0,1]` giving the significance level of the
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hypothesis test. Default: `0.05`.
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options.alternative: string (optional)
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Either `two-sided`, `less` or `greater`.
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options.ratio: number (optional)
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Positive number denoting the ratio of the two population variances under
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the null hypothesis. Default: `1`.
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Returns
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-------
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out: Object
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Test result object.
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out.alpha: number
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Used significance level.
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out.rejected: boolean
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Test decision.
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out.pValue: number
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p-value of the test.
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out.statistic: number
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Value of test statistic.
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out.ci: Array<number>
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1-alpha confidence interval for the ratio of variances.
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out.nullValue: number
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Assumed ratio of variances under H0.
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out.xvar: number
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Sample variance of `x`.
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out.yvar: number
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Sample variance of `y`.
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out.alternative: string
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Alternative hypothesis (`two-sided`, `less` or `greater`).
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out.dfX: number
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Numerator degrees of freedom.
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out.dfY: number
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Denominator degrees of freedom.
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out.method: string
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Name of test.
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out.print: Function
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Function to print formatted output.
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Examples
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--------
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> var x = [ 610, 610, 550, 590, 565, 570 ];
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> var y = [ 560, 550, 580, 550, 560, 590, 550, 590 ];
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> var out = {{alias}}( x, y )
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{
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rejected: false,
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pValue: ~0.399,
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statistic: ~1.976,
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ci: [ ~0.374, ~13.542 ],
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// ...
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}
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// Print table output:
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> var table = out.print()
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F test for comparing two variances
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Alternative hypothesis: True ratio in variances is not equal to 1
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pValue: 0.3992
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statistic: 1.976
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variance of x: 617.5 (df of x: 5)
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variance of y: 312.5 (df of y: 7)
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95% confidence interval: [0.3739,13.5417]
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Test Decision: Fail to reject null in favor of alternative at 5%
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significance level
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See Also
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--------
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