AR_Star

scalation.modeling.forecasting.multivar.AR_Star
See theAR_Star companion object
class AR_Star(y: MatrixD, hh: Int, fname: Array[String] = ..., tRng: Range = ..., hparam: HyperParameter = ...) extends Diagnoser, ForecastTensor, Forecast, NoSubModels

The AR_Star object is used to make an array of Auto-Regressive models, e.g., one for each variable in a multi-variate time series.

Value parameters

fname

the feature/variable names

hh

the maximum forecasting horizon (h = 1 to hh)

hparam

the hyper-parameters (defaults to `AR.hp')

tRng

the time range, if relevant (time index may suffice)

y

the response/output matrix (multi-variate time series data)

Attributes

Companion
object
Graph
Supertypes
trait NoSubModels
trait Forecast
trait Model
class Diagnoser
trait Fit
trait FitM
class Object
trait Matchable
class Any
Show all

Members list

Value members

Concrete methods

def forecastAll(y_: MatrixD = ...): TensorD

For each model, forecast values for all y_.dim time points and all horizons (1 through hh-steps ahead). Record these in the FORECAST TENSOR yf.

For each model, forecast values for all y_.dim time points and all horizons (1 through hh-steps ahead). Record these in the FORECAST TENSOR yf.

Value parameters

y_

the actual values to use in making forecasts

Attributes

override def getFname: Array[String]

Return the feature/variable names. Overrides definition in Forecast trait.

Return the feature/variable names. Overrides definition in Forecast trait.

Attributes

Definition Classes
def getY: VectorD

Return the used response vector y. Mainly for derived classes where y is transformed, e.g., TranRegression, ARX.

Return the used response vector y. Mainly for derived classes where y is transformed, e.g., TranRegression, ARX.

Attributes

Return the model hyper-parameters (if none, return null). Hyper-parameters may be used to regularize parameters or tune the optimizer.

Return the model hyper-parameters (if none, return null). Hyper-parameters may be used to regularize parameters or tune the optimizer.

Attributes

def inSample_Test(skip: Int, showYp: Boolean): (VectorD, VectorD)

Perform In-Sample Testing, i.e., train and test on the same FULL data set. Good for initial testing and understanding variable relationships. Return the prediction and the Quality of Fit.

Perform In-Sample Testing, i.e., train and test on the same FULL data set. Good for initial testing and understanding variable relationships. Return the prediction and the Quality of Fit.

Value parameters

showYp

whether to show the prediction vector

skip

the number of initial data points to skip (due to insufficient information)

Attributes

Note

May lead to over-fitting for complex models.

Return the vector of model parameter/coefficient values. Single output models have VectorD parameters, while multi-output models have MatrixD.

Return the vector of model parameter/coefficient values. Single output models have VectorD parameters, while multi-output models have MatrixD.

Attributes

def rollValidate(rc: Int = ..., growing: Boolean = ...): TensorD

For each model, use rolling-validation to compute test Quality of Fit (QoF) measures by dividing the dataset into a TRAINING SET (tr) and a TESTING SET (te). as follows: [ <-- tr_size --> | <-- te_size --> ] Record the forecasted values in the FORECAST TENSOR yf.

For each model, use rolling-validation to compute test Quality of Fit (QoF) measures by dividing the dataset into a TRAINING SET (tr) and a TESTING SET (te). as follows: [ <-- tr_size --> | <-- te_size --> ] Record the forecasted values in the FORECAST TENSOR yf.

Value parameters

growing

whether the training grows as it roll or kepps a fixed size

rc

the retraining cycle (number of forecasts until retraining occurs)

Attributes

def test(x_: MatrixD, y_: VectorD): (VectorD, VectorD)

Test/evaluate the model's Quality of Fit (QoF) and return the predictions and QoF vectors. This may include the importance of its parameters (e.g., if 0 is in a parameter's confidence interval, it is a candidate for removal from the model). Extending traits and classes should implement various diagnostics for the test and full (training + test) datasets.

Test/evaluate the model's Quality of Fit (QoF) and return the predictions and QoF vectors. This may include the importance of its parameters (e.g., if 0 is in a parameter's confidence interval, it is a candidate for removal from the model). Extending traits and classes should implement various diagnostics for the test and full (training + test) datasets.

Value parameters

x_

the testing/full data/input matrix (impl. classes may default to x)

y_

the testing/full response/output vector (impl. classes may default to y)

Attributes

def trainNtest(y_: MatrixD = ...)(yy: MatrixD = ...): Unit

Train and test each forecasting model y_ = f(y-past) + e and report its QoF and plot its predictions.

Train and test each forecasting model y_ = f(y-past) + e and report its QoF and plot its predictions.

Value parameters

y_

the training/full response/output vector (defaults to full y)

yy

the testing/full response/output vector (defaults to full y)

Attributes

def validate(rando: Boolean, ratio: Double)(idx: IndexedSeq[Int]): (VectorD | MatrixD, VectorD | MatrixD)

Inherited methods

inline def PIbounds(yp: VectorD, ihw_: MatrixD): (MatrixD, MatrixD)

Attributes

Inherited from:
Fit
inline def PIbounds(yp: VectorD, ihw: VectorD): (VectorD, VectorD)

Make the PREDICTION INTERVAL (PI) lower and upper bound vectors from the point predictions and the interval half widths.

Make the PREDICTION INTERVAL (PI) lower and upper bound vectors from the point predictions and the interval half widths.

Value parameters

ihw

the vector of interval half widths (one for each prediction)

yp

the vector of point predictions (y-hat)

Attributes

Inherited from:
Fit
def buildModel(x_cols: MatrixD, fname2: Array[String] = ...): Predictor & Fit

Build a sub-model that is restricted to the given columns of the data matrix. Must be implemented for models that support feature selection. NOT SUPPORTED for this model, so throw an EXCEPTION.

Build a sub-model that is restricted to the given columns of the data matrix. Must be implemented for models that support feature selection. NOT SUPPORTED for this model, so throw an EXCEPTION.

Value parameters

fname2

the variable/feature names for the new model (defaults to null)

x_cols

the columns that the new model is restricted to

Attributes

Inherited from:
NoSubModels
def cap: Int

Return the maximum lag used by the model (its capacity to look into the past). Models that use more than one past value to make predictions/forecasts must override this method, e.g., ARMA (2, 3) should set the cap to max(p, q) = 3.

Return the maximum lag used by the model (its capacity to look into the past). Models that use more than one past value to make predictions/forecasts must override this method, e.g., ARMA (2, 3) should set the cap to max(p, q) = 3.

Attributes

Inherited from:
Forecast
def crossValidate(k: Int, rando: Boolean): Array[Statistic]

The standard signature for prediction does not apply to time series.

The standard signature for prediction does not apply to time series.

Attributes

Inherited from:
Forecast
override def diagnose(y: VectorD, yp: VectorD, w: VectorD = ...): VectorD

Diagnose the health of the model by computing the Quality of Fit (QoF) measures, from the error/residual vector and the predicted & actual responses. For some models the instances may be weighted. For time series, the first few predictions use only part of the model, so may be skipped.

Diagnose the health of the model by computing the Quality of Fit (QoF) measures, from the error/residual vector and the predicted & actual responses. For some models the instances may be weighted. For time series, the first few predictions use only part of the model, so may be skipped.

Value parameters

w

the weights on the instances (defaults to null)

y

the actual response/output vector to use (test/full)

yp

the predicted response/output vector (test/full)

Attributes

Definition Classes
Inherited from:
Diagnoser
def diagnoseAll(yy: TensorD, yf: TensorD): Unit

Diagnose the health of the model by computing the Quality of Fit (QoF) measures, for all horizons and print the results in a table. For time series, the first few predictions use only part of the model, so may be skipped. The version is for models that perform DIRECT multi-horizon forecasting.

Diagnose the health of the model by computing the Quality of Fit (QoF) measures, for all horizons and print the results in a table. For time series, the first few predictions use only part of the model, so may be skipped. The version is for models that perform DIRECT multi-horizon forecasting.

Value parameters

yf

the entire FORECAST TENSOR

yy

the actual response/output matrix over all horizons

Attributes

Inherited from:
ForecastTensor
def diagnoseAll(y_: MatrixD, yf: TensorD, tRng: Range = ..., sft: Int = ...): Unit

Diagnose the health of the model by computing the Quality of Fit (QoF) measures, for all horizons and print the results in a table. For time series, the first few predictions use only part of the model, so may be skipped. The version is for models that perform RECURSIVE multi-horizon forecasting.

Diagnose the health of the model by computing the Quality of Fit (QoF) measures, for all horizons and print the results in a table. For time series, the first few predictions use only part of the model, so may be skipped. The version is for models that perform RECURSIVE multi-horizon forecasting.

Value parameters

rRng

the time range, defaults to null (=> full time range)

sft

the amount of shift for yfh (FIX - ideally unify the code and remove sft)

y_

the actual multi-variate time series matrix to use in making forecasts

yf

the entire FORECAST TENSOR

Attributes

Inherited from:
ForecastTensor
def diagnose_(y: VectorD, yp: VectorD, low_up: (VectorD, VectorD), α: Double = ..., w: VectorD = ...): VectorD

Diagnose the health of the model by computing the Quality of Fit (QoF) metrics/measures, from the error/residual vector and the predicted & actual responses. For some models the instances may be weighted. This method also includes PREDICTION INTERVAL (PI) metrics/measures.

Diagnose the health of the model by computing the Quality of Fit (QoF) metrics/measures, from the error/residual vector and the predicted & actual responses. For some models the instances may be weighted. This method also includes PREDICTION INTERVAL (PI) metrics/measures.

Value parameters

low_up

the predicted (lower, upper) bounds vectors

w

the weights on the instances (defaults to null)

y

the actual response/output vector to use (test/full)

yp

the point prediction mean/median

α

the significance/nominal level of uncertainty (α) (defaults to 0.1, 10%)

Attributes

See also

otexts.com/fpp2/prediction-intervals.html Note: wis should be computed separately as the bounds are matrices.

Inherited from:
Fit
def diagnose_mat(yy: MatrixD, yyp: MatrixD, w: VectorD = ...): MatrixD

Diagnose the health of the model by computing the Quality of Fit (QoF) measures, from the predicted & actual matrix responses (output variable per column). For some models the instances may be weighted.

Diagnose the health of the model by computing the Quality of Fit (QoF) measures, from the predicted & actual matrix responses (output variable per column). For some models the instances may be weighted.

Value parameters

w

the weights on the instances (defaults to null)

yy

the actual response/output matrix to use (test/full)

yyp

the predicted response/output matrix (test/full)

Attributes

See also

Regression_WLS

Inherited from:
Fit
def diagnose_pi(y: VectorD, yp: VectorD, low_up: (MatrixD, MatrixD), α: VectorD = ..., : Int = ...): (VectorD, Int)

Diagnose the health of the model by computing the Quality of Fit (QoF) measures for both POINT PREDICTIONS and PREDICTION INTERVALS.

Diagnose the health of the model by computing the Quality of Fit (QoF) measures for both POINT PREDICTIONS and PREDICTION INTERVALS.

Value parameters

the index for the main significance level out of the vector α

low_up

the predicted (lower, upper) bounds matrices for various α levels (column for each α level)

y

the given time-series (must be aligned with the interval forecast)

yp

the point prediction mean/median

α

the vector of significance levels (defaults to the K = 11 prediction intervals used by the CDC Forecast Hub)

Attributes

Inherited from:
Fit
def diagnose_wis(y: VectorD, yp: VectorD, low_up: (MatrixD, MatrixD), α: VectorD = ...): Double

Diagnose the health of the model by computing the Quality of Fit (QoF) measures, specifically for the weighted interval score that allows using custom α levels.

Diagnose the health of the model by computing the Quality of Fit (QoF) measures, specifically for the weighted interval score that allows using custom α levels.

Value parameters

low_up

the predicted (lower, upper) bounds matrices for various α levels (column for each α level)

y

the given time-series (must be aligned with the interval forecast)

yp

the point prediction mean/median

α

the vector of significance levels (defaults to the K = 11 prediction intervals used by the CDC Forecast Hub)

Attributes

Inherited from:
Fit

Return the diagonalized version of the forecst tensor, i.e., for each of the j-th forecast matrices each row is at a fixed time point and, for example, the random walk model simply pushes the values down diagonals. Note 'unshiftDiag' reverses the process.

Return the diagonalized version of the forecst tensor, i.e., for each of the j-th forecast matrices each row is at a fixed time point and, for example, the random walk model simply pushes the values down diagonals. Note 'unshiftDiag' reverses the process.

Value parameters

yf

the current forecast tensor

Attributes

Inherited from:
ForecastTensor
def equation: String

Print the model prediction equation in readable form. Override per model.

Print the model prediction equation in readable form. Override per model.

Attributes

Inherited from:
Model
def equationLaTeX: String

Print the model prediction equation in LaTex form. Override per model.

Print the model prediction equation in LaTex form. Override per model.

Attributes

Inherited from:
Model
override def fit: VectorD

Return the Quality of Fit (QoF) measures corresponding to the labels given. Note, if sse > sst, the model introduces errors and the rSq may be negative, otherwise, R^2 (rSq) ranges from 0 (weak) to 1 (strong). Override to add more quality of fit measures.

Return the Quality of Fit (QoF) measures corresponding to the labels given. Note, if sse > sst, the model introduces errors and the rSq may be negative, otherwise, R^2 (rSq) ranges from 0 (weak) to 1 (strong). Override to add more quality of fit measures.

Attributes

Definition Classes
Fit -> FitM
Inherited from:
Fit

Return the best model found from feature selection.

Return the best model found from feature selection.

Attributes

Inherited from:
NoSubModels
def getX: MatrixD

Return the used data/input matrix. Model that use x should override.

Return the used data/input matrix. Model that use x should override.

Attributes

Inherited from:
Forecast
def getXy: MatrixD

Return the data matrix x concatenated with response vector y.

Return the data matrix x concatenated with response vector y.

Attributes

Inherited from:
Model

Return the y-transformation.

Return the y-transformation.

Attributes

Inherited from:
Fit
def getYY: MatrixD

Return the used response matrix y, if needed.

Return the used response matrix y, if needed.

Attributes

See also

neuralnet.PredictorMV

Inherited from:
Model
override def help: String

Return the help string that describes the Quality of Fit (QoF) measures provided by the Fit trait. Override to correspond to fitLabel.

Return the help string that describes the Quality of Fit (QoF) measures provided by the Fit trait. Override to correspond to fitLabel.

Attributes

Definition Classes
Fit -> FitM
Inherited from:
Fit
def ll(ms: Double = ..., s2: Double = ..., m2: Int = ...): Double

The log-likelihood function times -2. Override as needed.

The log-likelihood function times -2. Override as needed.

Value parameters

ms

raw Mean Squared Error

s2

MLE estimate of the population variance of the residuals

Attributes

See also
Inherited from:
Fit
def makeForecastTensor(y_: MatrixD = ..., hh_: Int = ...): TensorD

Make the full FORECAST TENSOR where (for each sheet j) the zeroth column holds the actual time series and the last column is its time/time index. Columns 1, 2, ... hh are for h steps ahead forecasts.

Make the full FORECAST TENSOR where (for each sheet j) the zeroth column holds the actual time series and the last column is its time/time index. Columns 1, 2, ... hh are for h steps ahead forecasts.

Value parameters

hh

the maximum forecasting horizon, number of steps ahead to produce forecasts

y_

the actual multi-variate times values to use in making forecasts

Attributes

Inherited from:
ForecastTensor
def mod_resetDF(size: Int): Unit

Models need to provide a means for updating the Degrees of Freedom (DF). Note: Degrees of Freedom are mainly relevant for full and train, not test.

Models need to provide a means for updating the Degrees of Freedom (DF). Note: Degrees of Freedom are mainly relevant for full and train, not test.

Value parameters

size

the size of dataset (full, train, or test sets)

Attributes

Inherited from:
Diagnoser
inline def modelName: String

Get the model name.

Get the model name.

Attributes

Inherited from:
Model
inline def mse_: Double

Return the mean of the squares for error (sse / df). Must call diagnose first.

Return the mean of the squares for error (sse / df). Must call diagnose first.

Attributes

Inherited from:
Fit
def predict(z: VectorD): Double

The standard signature for prediction does not apply to time series.

The standard signature for prediction does not apply to time series.

Attributes

Inherited from:
Forecast
def predictInt(x_: MatrixD, df_: Double = ..., α: Double = ...): VectorD

Produce a PREDICTION INTERVAL half width for each prediction yp (y-hat).

Produce a PREDICTION INTERVAL half width for each prediction yp (y-hat).

Value parameters

df_

the error/residual degrees of freedom

x_

the testing/full data/input matrix

α

the significance level α = .1 for TWO TAILS: left tail .05 | 1 - α = .90 | .05 right tail e.g., for AutoMPG, t_crit (385, 0.90) = 1.6488210657096942 t_crit (385, 0.95) = 1.966

Attributes

See also

predictCInt in Predictor

stats.stackexchange.com/questions/585660/what-is-the-formula-for-prediction-interval-in-multivariate-case

Inherited from:
Fit
def predictInt_(x_: MatrixD, df_: Double = ..., α: VectorD = ...): MatrixD

Produce a PREDICTION INTERVAL half width for each prediction yp (y-hat) and each significance level.

Produce a PREDICTION INTERVAL half width for each prediction yp (y-hat) and each significance level.

Value parameters

df_

the error/residual degrees of freedom

x_

the testing/full data/input matrix

α

the significance levels to be used (defaults to Fit.α_)

Attributes

Inherited from:
Fit
def qof2Stat(qof: VectorD): Array[Statistic]

Convert QoF results into an array (of size 1) of Statistic for compatibility with the crossValidate method.

Convert QoF results into an array (of size 1) of Statistic for compatibility with the crossValidate method.

Value parameters

qof

the Quality of Fit (QoF) results

Attributes

Inherited from:
Model
inline def rSq0_: Double

Attributes

Inherited from:
FitM
inline def rSq_: Double

Return the coefficient of determination (R^2). Must call diagnose first.

Return the coefficient of determination (R^2). Must call diagnose first.

Attributes

Inherited from:
FitM
def report(ftMat: MatrixD): String

Return a basic report on a trained and tested multi-variate model.

Return a basic report on a trained and tested multi-variate model.

Value parameters

ftMat

the matrix of qof values produced by the Fit trait

Attributes

Inherited from:
Model
def report(ftVec: VectorD): String

Return a basic report on a trained and tested model.

Return a basic report on a trained and tested model.

Value parameters

ftVec

the vector of qof values produced by the Fit trait

Attributes

Inherited from:
Model
def resetDF(df_update: (Double, Double)): Unit

Reset the degrees of freedom to the new updated values. For some models, the degrees of freedom is not known until after the model is built.

Reset the degrees of freedom to the new updated values. For some models, the degrees of freedom is not known until after the model is built.

Value parameters

df_update

the updated degrees of freedom (regression/model, error)

Attributes

Inherited from:
Fit
def screen(xy: MatrixD, thr1: Double = ..., thr2: Double = ...)(dep: MatrixD = ...): (MatrixD, VectorI)

Screen the x-columns of matrix xy based on the two thresholds, returning the reduced matrix and the column indices/predictor variables selected.

Screen the x-columns of matrix xy based on the two thresholds, returning the reduced matrix and the column indices/predictor variables selected.

Value parameters

dep

the variable/column dependency measure (defaults to correlation)

thr1

the threshold used to compare the predictor x-columns to the y-column only want variables above some minimal dependency level

thr2

the threshold used to compare the predictor x-columns with each other only want variables below some cut-off dependency/collinearity level

xy

the [ x, y ] combined data-response matrix

Attributes

Inherited from:
Model
def setSkip(skip_: Int): Unit

Set the number of data points/elements to skip at the beginning of a time series for purposes of diagnosis or computing a loss function. For In-Sample, the first value (time t = 0) is not forecastable without backcasting.

Set the number of data points/elements to skip at the beginning of a time series for purposes of diagnosis or computing a loss function. For In-Sample, the first value (time t = 0) is not forecastable without backcasting.

Value parameters

skip

skip this many elements at the beginning of the time series

Attributes

Inherited from:
Diagnoser
def showQoF(qof: VectorD): Unit

Show the QoF metrics/measures in vector qof.

Show the QoF metrics/measures in vector qof.

Value parameters

qof

the QoF metrics (e.g., for point and interval predictions/forecasts)

Attributes

Inherited from:
Fit
inline def sse_: Double

Return the sum of the squares for error (sse). Must call diagnose first.

Return the sum of the squares for error (sse). Must call diagnose first.

Attributes

Inherited from:
FitM
def ssef(y: VectorD, yp: VectorD): Double

Compute the sum of squares errors (loss function), assuming the first 'skip' errors are zero.

Compute the sum of squares errors (loss function), assuming the first 'skip' errors are zero.

Value parameters

y

the actual response vector

yp

the predicted response vector (one-step ahead)

Attributes

Inherited from:
Diagnoser
override def summary(x_: MatrixD = ..., fname: Array[String] = ..., b: VectorD = ..., vifs: VectorD = ...): String

Produce a QoF SUMMARY for a model with diagnostics for each predictor x_j and the overall Quality of Fit (QoF). Note: `Fac_Cholesky is used to compute the inverse of xtx.

Produce a QoF SUMMARY for a model with diagnostics for each predictor x_j and the overall Quality of Fit (QoF). Note: `Fac_Cholesky is used to compute the inverse of xtx.

Value parameters

b

the parameters/coefficients for the model

fname

the array of feature/variable names

vifs

the Variance Inflation Factors (VIFs)

x_

the testing/full data/input matrix

Attributes

Definition Classes
Fit -> FitM
Inherited from:
Fit
inline def taskType: TaskType

Get the type of the task performed by model.

Get the type of the task performed by model.

Attributes

Inherited from:
Model
def train(x_null: MatrixD, y_: VectorD): Unit

Given a time series y_, train the forecasting function y_ = f(lags (y_)) + e, where f(lags (y_)) is a function of the lagged values of y_, by fitting its parameters.

Given a time series y_, train the forecasting function y_ = f(lags (y_)) + e, where f(lags (y_)) is a function of the lagged values of y_, by fitting its parameters.

Value parameters

x_null

the data/input matrix (ignored, pass null)

y_

the testing/full response/output vector (e.g., full y)

Attributes

Inherited from:
Forecast

Inherited fields

var modelConcept: URI

The optional reference to an ontological concept

The optional reference to an ontological concept

Attributes

Inherited from:
Model
protected var skip: Int

Attributes

Inherited from:
Diagnoser