ceTkinv: Cuzick and Edwards T_k^{inv} Test statistic

Description Usage Arguments Value Author(s) References See Also Examples

Description

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

T_k^{inv} test statistic is an extension of the run length test allowing a fixed number of controls in the run sequence.

T_k^{inv} test statistic is defined as T_k^{inv}=∑_{i=1}^n δ_i ν_i^k where δ_i=1 if z_i is a case, and 0 if z_i is a control and ν_i^k is the number of cases closer to the index case than the k nearest control, i.e., number of cases encountered beginning at z_i until k-th control is encountered.

The argument cc.lab is case-control label, 1 for case, 0 for control, if the argument case.lab is NULL, then cc.lab should be provided in this fashion, if case.lab is provided, the labels are converted to 0's and 1's accordingly.

Usage

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ceTkinv(dat, k, cc.lab, case.lab = NULL, ...)

Arguments

dat

The data set in one or higher dimensions, each row corresponds to a data point.

k

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

cc.lab

Case-control labels, 1 for case, 0 for control

case.lab

The label used for cases in the cc.lab (if cc.lab is not provided then the labels are converted such that cases are 1 and controls are 0), default is NULL.

...

are for further arguments, such as method and p, passed to the dist function.

Value

A list with two elements

Tkinv

Cuzick and Edwards T_k^{inv} test statistic for disease clustering

run.vec

The vector of number of cases till the k-th control for each point in the data set

Author(s)

Elvan Ceyhan

References

\insertAllCited

See Also

ceTrun, ceTk, and Tcomb

Examples

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n<-20
Y<-matrix(runif(3*n),ncol=3)
cls<-sample(0:1,n,replace = TRUE)  #or try cls<-rep(0:1,c(10,10))
cls
k<-2 #also try 3,4

ceTkinv(Y,k,cls)
ceTkinv(Y,k,cls+1,case.lab = 2)
ceTkinv(Y,k,cls,method="max")

ceTrun(Y,cls)
ceTkinv(Y,k=1,cls)

#cls as a factor
na<-floor(n/2); nb<-n-na
fcls<-rep(c("a","b"),c(na,nb))
ceTkinv(Y,k,fcls,case.lab="a") #try also ceTrun(Y,fcls)

#############
n<-40
Y<-matrix(runif(3*n),ncol=3)
cls<-sample(1:4,n,replace = TRUE)  #here ceTkinv(Y,k,cls) #gives error

nnspat documentation built on May 10, 2021, 9:06 a.m.