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External module "node_modules/@modelx/data/src/util"

Index

Type aliases

InputComponents

InputComponents: { average?: number; maximum?: number; minimum?: number; standard_dev?: number }

Type declaration

  • Optional average?: number
  • Optional maximum?: number
  • Optional minimum?: number
  • Optional standard_dev?: number

ScaledTransforms

ScaledTransforms: { components: InputComponents; descale: (x: number) => number; scale: (x: number) => number; values: number[] }

Type declaration

  • components: InputComponents
  • descale: (x: number) => number
      • (x: number): number
      • Parameters

        • x: number

        Returns number

  • scale: (x: number) => number
      • (x: number): number
      • Parameters

        • x: number

        Returns number

  • values: number[]

Variables

Const avg

avg: ArrayCalculation = ArrayStat.mean

Const max

max: ArraySort = ArrayStat.max

Const mean

mean: ArrayCalculation = avg

Const min

min: ArraySort = ArrayStat.min

Const sd

sd: ArrayCalculation = ArrayStat.standardDeviation

Const sum

sum: ArrayCalculation = ArrayStat.sum

Functions

MADMeanRatio

  • MADMeanRatio(actuals: number[], estimates: number[]): number
  • MAD over Mean Ratio - The MAD/Mean ratio is an alternative to the MAPE that is better suited to intermittent and low-volume data. As stated previously, percentage errors cannot be calculated when the actual equals zero and can take on extreme values when dealing with low-volume data. These issues become magnified when you start to average MAPEs over multiple time series. The MAD/Mean ratio tries to overcome this problem by dividing the MAD by the Mean—essentially rescaling the error to make it comparable across time series of varying scales

    memberof

    util

    see

    https://www.forecastpro.com/Trends/forecasting101August2011.html

    example

    const actuals = [ 45, 38, 43, 39 ]; const estimates = [ 41, 43, 41, 42 ]; const MMR = ms.util.MADMeanRatio(actuals, estimates); MAPE.toFixed(2) // => 0.08

    Parameters

    • actuals: number[]

      numerical samples

    • estimates: number[]

      estimates values

    Returns number

    MMR

Const MinMaxScaler

  • MinMaxScaler(z: number[]): number[]
  • Transforms features by scaling each feature to a given range. This estimator scales and translates each feature individually such that it is in the given range on the training set, i.e. between zero and one.

    Parameters

    • z: number[]

      array of integers or floats

    Returns number[]

MinMaxScalerTransforms

  • This function returns two functions that can mix max scale new inputs and reverse scale new outputs

    Parameters

    • Default value vector: any[] = []
    • Default value nan_value: number = -1
    • Default value return_nan: boolean = false
    • Default value inputComponents: InputComponents = {}

    Returns ScaledTransforms

    • {scale[ Function ], descale[ Function ]}

Const StandardScaler

  • StandardScaler(z: number[]): number[]
  • Standardize features by removing the mean and scaling to unit variance

    Centering and scaling happen independently on each feature by computing the relevant statistics on the samples in the training set. Mean and standard deviation are then stored to be used on later data using the transform method.

    Standardization of a dataset is a common requirement for many machine learning estimators: they might behave badly if the individual feature do not more or less look like standard normally distributed data (e.g. Gaussian with 0 mean and unit variance)

    Parameters

    • z: number[]

      array of integers or floats

    Returns number[]

StandardScalerTransforms

  • This function returns two functions that can standard scale new inputs and reverse scale new outputs

    Parameters

    • Default value vector: any[] = []
    • Default value nan_value: number = -1
    • Default value return_nan: boolean = false
    • Default value inputComponents: InputComponents = {}

    Returns ScaledTransforms

    • {scale[ Function ], descale[ Function ]}

adjustedCoefficentOfDetermination

  • adjustedCoefficentOfDetermination(options: { actuals: number[]; estimates: number[]; independentVariables: number; rSquared: number; sampleSize: number }): number
  • You can use the adjusted coefficient of determination to determine how well a multiple regression equation “fits” the sample data. The adjusted coefficient of determination is closely related to the coefficient of determination (also known as R2) that you use to test the results of a simple regression equation.

    example

    const adjr2 = ms.util.adjustedCoefficentOfDetermination({ rSquared: 0.944346527, sampleSize: 8, independentVariables: 2, }); r2.toFixed(3) // => 0.922

    memberof

    util

    see

    http://www.dummies.com/education/math/business-statistics/how-to-calculate-the-adjusted-coefficient-of-determination/

    Parameters

    • options: { actuals: number[]; estimates: number[]; independentVariables: number; rSquared: number; sampleSize: number }
      • actuals: number[]
      • estimates: number[]
      • independentVariables: number

        the number of independent variables in the regression equation

      • rSquared: number
      • sampleSize: number

    Returns number

    adjusted r^2 for multiple linear regression

approximateZPercentile

  • approximateZPercentile(z: number, alpha?: boolean): number

coefficientOfCorrelation

  • coefficientOfCorrelation(actuals?: number[], estimates?: number[]): number
  • The coefficent of Correlation is given by R decides how well the given data fits a line or a curve.

    example

    const actuals = [ 39, 42, 67, 76, ]; const estimates = [ 44, 40, 60, 84, ]; const R = ms.util.coefficientOfCorrelation(actuals, estimates); R.toFixed(4) // => 0.9408

    memberof

    util

    see

    https://calculator.tutorvista.com/r-squared-calculator.html

    Parameters

    • Default value actuals: number[] = []

      numerical samples

    • Default value estimates: number[] = []

      estimates values

    Returns number

    R

coefficientOfDetermination

  • coefficientOfDetermination(actuals?: number[], estimates?: number[]): number
  • In statistics, the coefficient of determination, denoted R2 or r2 and pronounced "R squared", is the proportion of the variance in the dependent variable that is predictable from the independent variable(s). Compares distance of estimated values to the mean. {\bar {y}}={\frac {1}{n}}\sum {i=1}^{n}y{i}

    example

    const actuals = [ 2, 4, 5, 4, 5, ]; const estimates = [ 2.8, 3.4, 4, 4.6, 5.2, ]; const r2 = ms.util.coefficientOfDetermination(actuals, estimates); r2.toFixed(1) // => 0.6

    memberof

    util

    see

    https://en.wikipedia.org/wiki/Coefficient_of_determination http://statisticsbyjim.com/regression/standard-error-regression-vs-r-squared/

    Parameters

    • Default value actuals: number[] = []

      numerical samples

    • Default value estimates: number[] = []

      estimates values

    Returns number

    r^2

forecastErrors

  • forecastErrors(actuals: number[], estimates: number[]): number[]
  • The errors (residuals) from acutals and estimates

    memberof

    util

    example

    const actuals = [ 45, 38, 43, 39 ]; const estimates = [ 41, 43, 41, 42 ]; const errors = ms.util.forecastErrors(actuals, estimates); // => [ 4, -5, 2, -3 ]

    Parameters

    • actuals: number[]

      numerical samples

    • estimates: number[]

      estimates values

    Returns number[]

    errors (residuals)

getSafePropertyName

  • getSafePropertyName(name: string): string
  • returns a safe column name / url slug from a string

    Parameters

    • name: string

    Returns string

meanAbsoluteDeviation

  • meanAbsoluteDeviation(actuals: number[], estimates: number[]): number
  • Mean Absolute Deviation (MAD) indicates the absolute size of the errors

    memberof

    util

    see

    https://scm.ncsu.edu/scm-articles/article/measuring-forecast-accuracy-approaches-to-forecasting-a-tutorial

    example

    const actuals = [ 45, 38, 43, 39 ]; const estimates = [ 41, 43, 41, 42 ]; const MAD = ms.util.meanAbsoluteDeviation(actuals, estimates); // => 3.5

    Parameters

    • actuals: number[]

      numerical samples

    • estimates: number[]

      estimates values

    Returns number

    MAD

meanAbsolutePercentageError

  • meanAbsolutePercentageError(actuals: number[], estimates: number[]): number
  • MAPE (Mean Absolute Percent Error) measures the size of the error in percentage terms

    memberof

    util

    see

    https://www.forecastpro.com/Trends/forecasting101August2011.html

    example

    const actuals = [ 45, 38, 43, 39 ]; const estimates = [ 41, 43, 41, 42 ]; const MAPE = ms.util.meanAbsolutePercentageError(actuals, estimates); MAPE.toFixed(2) // => 0.86

    Parameters

    • actuals: number[]

      numerical samples

    • estimates: number[]

      estimates values

    Returns number

    MAPE

meanForecastError

  • meanForecastError(actuals: number[], estimates: number[]): number

meanSquaredError

  • meanSquaredError(actuals: number[], estimates: number[]): number
  • The standard error of the estimate is a measure of the accuracy of predictions made with a regression line. Compares the estimate to the actual value

    memberof

    util

    see

    http://onlinestatbook.com/2/regression/accuracy.html

    example

    const actuals = [ 45, 38, 43, 39 ]; const estimates = [ 41, 43, 41, 42 ]; const MSE = ms.util.meanSquaredError(actuals, estimates); // => 13.5

    Parameters

    • actuals: number[]

      numerical samples

    • estimates: number[]

      estimates values

    Returns number

    MSE

pivotArrays

  • returns a matrix of values by combining arrays into a matrix

    memberof

    util

    example

    const arrays = [ [ 1, 1, 3, 3 ], [ 2, 2, 3, 3 ], [ 3, 3, 4, 3 ], ]; pivotArrays(arrays); //=> // [ // [1, 2, 3,], // [1, 2, 3,], // [3, 3, 4,], // [3, 3, 3,], // ];

    Parameters

    • Default value arrays: Matrix = []

    Returns Matrix

    a matrix of column values

pivotVector

  • returns an array of vectors as an array of arrays

    example

    const vectors = [ [1,2,3], [1,2,3], [3,3,4], [3,3,3] ]; const arrays = pivotVector(vectors); // => [ [1,2,3,3], [2,2,3,3], [3,3,4,3] ];

    memberof

    util

    Parameters

    • Default value vectors: Array<any>[] = []

    Returns Matrix

rSquared

  • rSquared(actuals?: number[], estimates?: number[]): number
  • The coefficent of determination is given by r^2 decides how well the given data fits a line or a curve.

    Parameters

    • Default value actuals: number[] = []
    • Default value estimates: number[] = []

    Returns number

    r^2

Const scale

  • scale(a: number[], d: number): number[]
  • Parameters

    • a: number[]
    • d: number

    Returns number[]

squaredDifference

  • squaredDifference(left: number[], right: number[]): number[]
  • Returns an array of the squared different of two arrays

    memberof

    util

    Parameters

    • left: number[]
    • right: number[]

    Returns number[]

    Squared difference of left minus right array

standardError

  • standardError(actuals?: number[], estimates?: number[]): number
  • The standard error of the estimate is a measure of the accuracy of predictions made with a regression line. Compares the estimate to the actual value

    memberof

    util

    see

    http://onlinestatbook.com/2/regression/accuracy.html

    example

    const actuals = [ 2, 4, 5, 4, 5, ]; const estimates = [ 2.8, 3.4, 4, 4.6, 5.2, ]; const SE = ms.util.standardError(actuals, estimates); SE.toFixed(2) // => 0.89

    Parameters

    • Default value actuals: number[] = []

      numerical samples

    • Default value estimates: number[] = []

      estimates values

    Returns number

    Standard Error of the Estimate

standardScore

  • standardScore(observations?: number[]): number[]
  • Calculates the z score of each value in the sample, relative to the sample mean and standard deviation.

    memberof

    util

    see

    https://docs.scipy.org/doc/scipy-0.14.0/reference/generated/scipy.stats.mstats.zscore.html

    Parameters

    • Default value observations: number[] = []

      An array like object containing the sample data.

    Returns number[]

    The z-scores, standardized by mean and standard deviation of input array

trackingSignal

  • trackingSignal(actuals: number[], estimates: number[]): number
  • Tracking Signal - Used to pinpoint forecasting models that need adjustment

    memberof

    util

    see

    https://scm.ncsu.edu/scm-articles/article/measuring-forecast-accuracy-approaches-to-forecasting-a-tutorial

    example

    const actuals = [ 45, 38, 43, 39 ]; const estimates = [ 41, 43, 41, 42 ]; const trackingSignal = ms.util.trackingSignal(actuals, estimates); trackingSignal.toFixed(2) // => -0.57

    Parameters

    • actuals: number[]

      numerical samples

    • estimates: number[]

      estimates values

    Returns number

    trackingSignal

Object literals

Const util

util: object
namespace

MAD

MAD: meanAbsoluteDeviation = meanAbsoluteDeviation

MADMeanRatio

MADMeanRatio: MADMeanRatio

MAPE

MAPE: meanAbsolutePercentageError = meanAbsolutePercentageError

MFE

MFE: meanForecastError = meanForecastError

MMR

MMR: MADMeanRatio = MADMeanRatio

MSE

MSE: meanSquaredError = meanSquaredError

MinMaxScaler

MinMaxScaler: MinMaxScaler

MinMaxScalerTransforms

MinMaxScalerTransforms: MinMaxScalerTransforms

StandardScaler

StandardScaler: StandardScaler

StandardScalerTransforms

StandardScalerTransforms: StandardScalerTransforms

TS

TS: trackingSignal = trackingSignal

adjustedCoefficentOfDetermination

adjustedCoefficentOfDetermination: adjustedCoefficentOfDetermination

adjustedRSquared

adjustedRSquared: adjustedCoefficentOfDetermination = adjustedCoefficentOfDetermination

approximateZPercentile

approximateZPercentile: approximateZPercentile

avg

coefficientOfCorrelation

coefficientOfCorrelation: coefficientOfCorrelation

coefficientOfDetermination

coefficientOfDetermination: coefficientOfDetermination

forecastErrors

forecastErrors: forecastErrors

getSafePropertyName

getSafePropertyName: getSafePropertyName

max

mean

mean: ArrayCalculation = avg

meanAbsoluteDeviation

meanAbsoluteDeviation: meanAbsoluteDeviation

meanAbsolutePercentageError

meanAbsolutePercentageError: meanAbsolutePercentageError

meanForecastError

meanForecastError: meanForecastError

meanSquaredError

meanSquaredError: meanSquaredError

min

pivotArrays

pivotArrays: pivotArrays

pivotVector

pivotVector: pivotVector

r

r: coefficientOfCorrelation = coefficientOfCorrelation

rBarSquared

rBarSquared: adjustedCoefficentOfDetermination = adjustedCoefficentOfDetermination

rSquared

rSquared: rSquared

range

range: range

rangeRight

rangeRight: any

scale

scale: scale

sd

squaredDifference

squaredDifference: squaredDifference

standardError

standardError: standardError

standardScore

standardScore: standardScore

sum

trackingSignal

trackingSignal: trackingSignal

zScore

zScore: standardScore = standardScore

ExpScaler

  • ExpScaler(z: number[]): number[]
  • Parameters

    • z: number[]

    Returns number[]

LogScaler

  • LogScaler(z: number[]): number[]
  • Parameters

    • z: number[]

    Returns number[]