Tcomb {nnspat} | R Documentation |
Cuzick & Edwards Tcomb Test Statistic
Description
This function computes the value of Cuzick & Edwards T_{comb}
test statistic in disease clustering, where T_{comb}
is a linear combination of some T_k
tests.
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.
The argument klist
is the vector
of integers specifying the indices of the T_k
values used
in obtaining the T_{comb}
.
The logical argument nonzero.mat
(default=TRUE
) is for using the A
matrix if FALSE
or just the matrix of nonzero
locations in the A
matrix (if TRUE
) in the computations.
The logical argument asy.cov
(default=FALSE
) is for using the asymptotic covariance or the exact (i.e., finite
sample) covariance for the vector of T_k
values used in Tcomb
in the standardization of T_{comb}
.
If asy.cov=TRUE
, the asymptotic covariance is used, otherwise the exact covariance is used.
See page 87 of (Cuzick and Edwards (1990)) for more details.
Usage
Tcomb(
dat,
cc.lab,
klist,
case.lab = NULL,
nonzero.mat = TRUE,
asy.cov = FALSE,
...
)
Arguments
dat |
The data set in one or higher dimensions, each row corresponds to a data point. |
cc.lab |
Case-control labels, 1 for case, 0 for control |
klist |
|
case.lab |
The label used for cases in the |
nonzero.mat |
A logical argument (default is |
asy.cov |
A logical argument (default is |
... |
are for further arguments, such as |
Value
Returns the value of the T_{comb}
test statistic
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
Examples
n<-20 #or try sample(1:20,1) #try also n<-50, 100
Y<-matrix(runif(3*n),ncol=3)
cls<-sample(0:1,n,replace = TRUE) #or try cls<-rep(0:1,c(10,10))
n1<-sum(cls==1)
kl<-sample(1:5,3) #try also sample(1:5,2)
kl
Tcomb(Y,cls,kl)
Tcomb(Y,cls,kl,method="max")
Tcomb(Y,cls+1,kl,case.lab=2)
Tcomb(Y,cls,kl,nonzero.mat = FALSE)
Tcomb(Y,cls,kl,asy.cov = TRUE)
#cls as a factor
na<-floor(n/2); nb<-n-na
fcls<-rep(c("a","b"),c(na,nb))
Tcomb(Y,fcls,kl,case.lab="a")