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pchc (version 1.2)

Skeleton of the FEDHC algorithm using the distance correlation: The skeleton of a Bayesian network produced by the FEDHC algorithm using the distance correlation

Description

The skeleton of a Bayesian network produced by the FEDHC algorithm using the distance correlation.

Usage

dcor.fedhc.skel(x, alpha = 0.05, ini.stat = NULL, R = NULL)

Value

A list including:

ini.stat

The test statistics of the univariate associations.

ini.pvalue

The initial p-values univariate associations.

pvalue

A matrix with the logarithm of the p-values of the updated associations. This final p-value is the maximum p-value among the two p-values in the end.

runtime

The duration of the algorithm.

ntests

The number of tests conducted during each k.

G

The adjancency matrix. A value of 1 in G[i, j] appears in G[j, i] also, indicating that i and j have an edge between them.

Arguments

x

A numerical matrix with the variables. If you have a data.frame (i.e. categorical data) turn them into a matrix using data.frame.to_matrix. Note, that for the categorical case data, the numbers must start from 0. No missing data are allowed.

alpha

The significance level (suitable values in (0, 1)) for assessing the p-values. Default value is 0.05.

ini.stat

If the initial test statistics (univariate associations) are available, pass them through this parameter.

R

If the correlation matrix is available, pass it here.

Author

Michail Tsagris.

R implementation and documentation: Michail Tsagris mtsagris@uoc.gr.

Details

As in FEDHC the first phase consists of a variable selection procedure, the FBED algortihm (Borboudakis and Tsamardinos, 2019) which is performed though by utilizing the distance correlation (Szekely et al., 2007, Szekely and Rizzo 2014, Huo and Szekely, 2016).

References

Tsagris M. (2022). The FEDHC Bayesian Network Learning Algorithm. Mathematics, 10(25): 2604.

Szekely G.J., Rizzo M.L. and Bakirov N.K. (2007). Measuring and Testing Independence by Correlation of Distances. Annals of Statistics, 35(6):2769-2794.

Szekely G.J. and Rizzo M. L. (2014). Partial distance correlation with methods for dissimilarities. Annals of Statistics, 42(6), 2382-2412.

Huo X. and Szekely G.J. (2016). Fast computing for distance covariance. Technometrics, 58(4), 435-447.

See Also

fedhc.skel, fedhc.skel.boot

Examples

Run this code
# simulate a dataset with continuous data
x <- matrix( rnorm(500 * 30, 1, 10), nrow = 500 )
a <- dcor.fedhc.skel(x)

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