# matddchisqsym: Matrix of distances between discrete probability densities... In dad: Three-Way / Multigroup Data Analysis Through Densities

## Description

Computes the matrix of the symmetric Chi-squared distances between several multivariate or univariate discrete probability distributions, estimated from samples.

## Usage

 `1` ```matddchisqsym(x) ```

## Arguments

 `x` object of class `"folder"` containing the data. Its elements are data frames (one data frame per distribution) whose columns are factors.

## Value

Positive symmetric matrix whose order is equal to the number of data frames (or distributions), consisting of the pairwise symmetric chi-squared distances between the distributions.

## Author(s)

Rachid Boumaza, Pierre Santagostini, Smail Yousfi, Sabine Demotes-Mainard

## References

Deza, M.M. and Deza E. (2013). Encyclopedia of distances. Springer.

`ddchisqsym`.
`matddchisqsympar` for discrete probability densities, given the probabilities on the same support.
 ``` 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16``` ```# Example 1 x1 <- data.frame(x = factor(c("A", "A", "B", "B"))) x2 <- data.frame(x = factor(c("A", "A", "A", "B", "B"))) x3 <- data.frame(x = factor(c("A", "A", "B", "B", "B", "B"))) xf <- folder(x1, x2, x3) matddchisqsym(xf) # Example 2 x1 <- data.frame(x = factor(c("A", "A", "A", "B", "B", "B")), y = factor(c("a", "a", "a", "b", "b", "b"))) x2 <- data.frame(x = factor(c("A", "A", "A", "B", "B")), y = factor(c("a", "a", "b", "a", "b"))) x3 <- data.frame(x = factor(c("A", "A", "B", "B", "B", "B")), y = factor(c("a", "b", "a", "b", "a", "b"))) xf <- folder(x1, x2, x3) matddchisqsym(xf) ```