# funsC_MI_II: Correction Matrices for the Covariance Matrix of NNCT entries In nnspat: Nearest Neighbor Methods for Spatial Patterns

 funsC_MI_II R Documentation

## Correction Matrices for the Covariance Matrix of NNCT entries

### Description

Two functions: `correct.cf1` and `correct.cf1`.

Each function yields matrices which are used in obtaining covariance matrices of T_{ij} values for types I and II tests from the usual Chi-Square test of contingency tables (i.e. Pielou's test) applied on NNCTs. The output matrices are to be term-by-term multiplied with the covariance matrix of the entries of NNCT. See Sections 3.1 and 3.2 in (\insertCiteceyhan:SJScorrected2010;textualnnspat) or Sections 3.5.1 and 3.5.2 in (\insertCiteECarXivCorrected:2008;textualnnspat) for more details.

### Usage

```correct.cf1(ct)

correct.cf2(ct)
```

### Arguments

 `ct` A nearest neighbor contingency table

### Value

Both functions return a correction matrix which is to be multiplied with the covariance matrix of entries of the NNCT so as to obtain types I and II overall tests from Pielou's test of segregation. See the description above for further detail.

Elvan Ceyhan

### References

\insertAllCited

`nnct.cr1` and `nnct.cr2`

### Examples

```n<-20  #or try sample(1:20,1)
Y<-matrix(runif(3*n),ncol=3)
ipd<-ipd.mat(Y)
cls<-sample(1:2,n,replace = TRUE)  #or try cls<-rep(1:2,c(10,10))
ct<-nnct(ipd,cls)

W<-Wmat(ipd)
Qv<-Qvec(W)\$q
Rv<-Rval(W)
varN<-var.nnct(ct,Qv,Rv)
covN<-cov.nnct(ct,varN,Qv,Rv)

#correction type 1
CM1<-correct.cf1(ct)
CovN.cf1<-covN*CM1

#correction type 2
CM2<-correct.cf2(ct)
CovN.cf2<-covN*CM2

covN
CovN.cf1
CovN.cf2

```

nnspat documentation built on Aug. 30, 2022, 9:06 a.m.