EV.Tkinv {nnspat}

Expected Value of Cuzick and Edwards T_k^{inv} Test statistic

Description

This function computes the expected value of Cuzick and Edwards T_k^{inv} test statistic which is based on the sum of number of cases closer to each case than the k-th nearest control to the case.

The number of cases are denoted as n_1 (denoted as n1 as an argument) and number of controls as n_0 for both functions (denoted as n0 as an argument), to match the case-control class labeling, which is just the reverse of the labeling in Cuzick and Edwards (1990).

See the function ceTkinv for the details of the T_k^{inv} test.

See (Cuzick and Edwards (1990)) and references therein.

Usage

EV.Tkinv(n1, n0, k)

Arguments

n1, n0

The number of cases and controls

k

Integer specifying the number of the closest controls to subject i.

Value

The expected value of Cuzick and Edwards T_k^{inv} test statistic for disease clustering

Author(s)

Elvan Ceyhan

References

Cuzick J, Edwards R (1990). “Spatial clustering for inhomogeneous populations (with discussion).” Journal of the Royal Statistical Society, Series B, 52, 73-104.

See Also

ceTkinv, ceTrun, and EV.Trun

Examples

n1<-20
n0<-25
k<-2 #try also 2, 3

EV.Tkinv(n1,n0,k)

EV.Tkinv(n1,n0,k=1)
EV.Trun(n1,n0)