R: Envelope of Khat from simulations of complete spatial...

Kenv.csr {splancs} | R Documentation

## Envelope of Khat from simulations of complete spatial randomness

### Description

Compute envelope of Khat from simulations of complete spatial randomness.

### Usage

    Kenv.csr(nptg,poly,nsim,s,quiet=FALSE)

### Arguments

`nptg` | Number of points to generate in each simulation.
`poly` | Polygon in which to generate the points.
`nsim` | Number of simulations to do.
`s` | Vector of distances at which to calculate the envelope.
`quiet` | If FALSE, print a message after every simulation for progress monitoring. If TRUE, print no messages.

### Value

A list with two components, called `$upper` and `$lower`. Each component is a vector like `s`. The two components contain the upper and lower bound of the Khat envelope.

### References

Rowlingson, B. and Diggle, P. 1993 Splancs: spatial point pattern analysis code in S-Plus. Computers and Geosciences, 19, 627-655; the original sources can be accessed at: http://www.maths.lancs.ac.uk/~rowlings/Splancs/. See also Bivand, R. and Gebhardt, A. 2000 Implementing functions for spatial statistical analysis using the R language. Journal of Geographical Systems, 2, 307-317.

### See Also

`csr`, `khat`

### Examples

    data(cardiff)
    UL.khat <- Kenv.csr(length(cardiff$x), cardiff$poly, nsim=29, seq(2,30,2))
    plot(seq(2,30,2), sqrt(khat(as.points(cardiff), cardiff$poly,
    seq(2,30,2))/pi)-seq(2,30,2), type="l", xlab="Splancs - polygon boundary",
    ylab="Estimated L", ylim=c(-1,1.5))
    lines(seq(2,30,2), sqrt(UL.khat$upper/pi)-seq(2,30,2), lty=2)
    lines(seq(2,30,2), sqrt(UL.khat$lower/pi)-seq(2,30,2), lty=2)

[Package splancs version 2.01-40 Index]