rEDM: Multiview – R documentation

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Multiview

Forecasting using multiview embedding

Description

Multiview applies the method of Ye & Sugihara to find optimal combinations of variables that best represent the dynamics.

Usage

Multiview(pathIn = "./", dataFile = "", dataFrame = NULL,
  lib = "", pred = "", D = 0, E = 1, Tp = 1, knn = 0, 
  tau = -1, columns = "", target = "", multiview = 0, exclusionRadius = 0,
  trainLib = TRUE, excludeTarget = FALSE, parameterList = FALSE,
  verbose = FALSE, numThreads = 4, showPlot = FALSE)

Arguments

`pathIn`	path to `dataFile`.
`dataFile`	.csv format data file name. The first column must be a time index or time values. The first row must be column names.
`dataFrame`	input data.frame. The first column must be a time index or time values. The columns must be named.
`lib`	a 2-column matrix, data.frame, 2-element vector or string of row indice pairs, where each pair specifies the first and last rows of the time series to create the library.
`pred`	(same format as lib), but specifying the sections of the time series to forecast.
`D`	multivariate dimension.
`E`	embedding dimension.
`Tp`	prediction horizon (number of time column rows).
`knn`	number of nearest neighbors. If knn=0, knn is set to E+1.
`tau`	lag of time delay embedding specified as number of time column rows.
`columns`	string of whitespace separated column name(s) in the input data used to create multivariable data sets.
`target`	column name in the input data used for prediction.
`multiview`	number of multiview ensembles to average for the final prediction estimate.
`exclusionRadius`	number of adjacent observation vector rows to exclude as nearest neighbors in prediction.
`trainLib`	logical to use in-sample (lib=pred) projections for the ranking of column combinations.
`excludeTarget`	logical to exclude embedded target column from combinations.
`parameterList`	logical to add list of invoked parameters.
`verbose`	logical to produce additional console reporting.
`numThreads`	number of CPU threads to use in multiview processing.
`showPlot`	logical to plot results.

Details

Multiview embedding is a method to identify variables in a multivariate dynamical system that are most likely to contribute to the observed dynamics. It is a multistep algorithm with these general steps:

Compute D-dimensional variable combination forecasts.
Rank forecasts.
Compute predictions of top combinations.
Compute multiview averaged prediction.

If E>1, all variables are embedded to dimension E. If trainLib is TRUE initial forecasts and ranking are done in-sample (lib=pred) and predictions using the top ranked combinations use the specified lib and pred. If trainLib is FALSE initial forecasts and ranking use the specified lib and pred, the step of computing predictions of the top combinations is skipped.

Value

Named list with data.frames [[Combo_rho, Predictions]].

data.frame Combo_rho columns:

Col_1	column index
...	column index
Col_E	column index
rho	Pearson correlation
MAE	mean absolute error
RMSE	root mean square error

If parameterList = TRUE a named list "parameters" is added.

References

Ye H., and G. Sugihara, 2016. Information leverage in interconnected ecosystems: Overcoming the curse of dimensionality. Science 353:922-925.

Examples

data(block_3sp)
L = Multiview( dataFrame = block_3sp, lib = "1 100", pred = "101 190",
E = 2, columns = "x_t y_t z_t", target = "x_t" )

rEDM

Empirical Dynamic Modeling ('EDM')

v1.10.0

BSD_2_clause + file LICENSE

Authors

Joseph Park [aut, cre] (<https://orcid.org/0000-0001-5411-1409>), Cameron Smith [aut] (<https://orcid.org/0000-0003-0020-5607>), George Sugihara [aut, ccp] (<https://orcid.org/0000-0002-2863-6946>), Ethan Deyle [aut] (<https://orcid.org/0000-0001-8704-8434>), Erik Saberski [ctb] (<https://orcid.org/0000-0002-6475-6187>), Hao Ye [ctb] (<https://orcid.org/0000-0002-8630-1458>), The Regents of the University of California [cph]

Initial release

2021-12-19