spatstat (version 1.55-0)

rcellnumber: Generate Random Numbers of Points for Cell Process

Description

Generates random integers for the Baddeley-Silverman counterexample.

Usage

rcellnumber(n, N = 10, mu=1)

Arguments

n

Number of random integers to be generated.

N

Distributional parameter: the largest possible value (when mu <= 1). An integer greater than 1.

mu

Mean of the distribution (equals the variance). Any positive real number.

Value

An integer vector of length n.

Details

If mu = 1 (the default), this function generates random integers which have mean and variance equal to 1, but which do not have a Poisson distribution. The random integers take the values \(0\), \(1\) and \(N\) with probabilities \(1/N\), \((N-2)/(N-1)\) and \(1/(N(N-1))\) respectively. See Baddeley and Silverman (1984).

If mu is another positive number, the random integers will have mean and variance equal to mu. They are obtained by generating the one-dimensional counterpart of the cell process and counting the number of points in the interval from 0 to mu. The maximum possible value of each random integer is N * ceiling(mu).

References

Baddeley, A.J. and Silverman, B.W. (1984) A cautionary example on the use of second-order methods for analyzing point patterns. Biometrics 40, 1089-1094.

See Also

rcell

Examples

# NOT RUN {
   rcellnumber(30, 3)
# }