# ssw: Compute the sum of dissimilarity In spdep: Spatial Dependence: Weighting Schemes, Statistics

 ssw R Documentation

## Compute the sum of dissimilarity

### Description

This function computes the sum of dissimilarity between each observation and the mean (scalar of vector) of the observations.

### Usage

```ssw(data, id, method = c("euclidean", "maximum",
"manhattan", "canberra", "binary", "minkowski",
"mahalanobis"), p = 2, cov, inverted = FALSE)
```

### Arguments

 `data` A matrix with observations in the nodes. `id` Node index to compute the cost `method` Character or function to declare distance method. If `method` is character, method must be "mahalanobis" or "euclidean", "maximum", "manhattan", "canberra", "binary" or "minkowisk". If `method` is one of "euclidean", "maximum", "manhattan", "canberra", "binary" or "minkowisk", see `dist` for details, because this function as used to compute the distance. If `method="mahalanobis"`, the mahalanobis distance is computed between neighbour areas. If `method` is a `function`, this function is used to compute the distance. `p` The power of the Minkowski distance. `cov` The covariance matrix used to compute the mahalanobis distance. `inverted` logical. If 'TRUE', 'cov' is supposed to contain the inverse of the covariance matrix.

### Value

A numeric, the sum of dissimilarity between the observations `id` of `data` and the mean (scalar of vector) of this observations.

### Author(s)

Elias T. Krainski and Renato M. Assuncao

See Also as `nbcost`

### Examples

```data(USArrests)
n <- nrow(USArrests)
ssw(USArrests, 1:n)
ssw(USArrests, 1:(n/2))
ssw(USArrests, (n/2+1):n)
ssw(USArrests, 1:(n/2)) + ssw(USArrests, (n/2+1):n)
```

spdep documentation built on April 18, 2022, 9:06 a.m.