Hi
I am working on educational assignment to produce an *Incidence matrix *from
a *BIB design *using R language software.
 I found a web page *http://wiki.math.yorku.ca/index.php/R:_Incidence_matrix
* about the problem. But it produces Data matrix instead of
Incidence matrix. can you please help me out using R software.

thanks and regards

zaheer

*following are the sample codes of my assignment  with resultant "Incidence
Matrix" as mentioned in above link, but this is, according to my knowledge,
Data matrix of any experimental design. *

 b=4                                   #Number of Blocks

 t=4                                   #Number of Column

     z=c(1,2,3)                        #Shift

m=NULL

     y=c(0)

 w=c(y,cumsum(z) %%t)

print("The Initial Block is=")

print(w)



 p=seq(from=0, to=t-1, by=1)

 l=NULL



   for(i in 1:b)

     {

         for(j in 1:t)

            {

                l=c(l,rep((w[i]+p[j]+t)%% t))

             }

      }



x= matrix(c(l),nrow=b,ncol=t,byrow = TRUE)

print("The Design Layout is ")

print.matrix <- function(x){



write.table(format(x, justify="right"),



                 row.names=F,col.names=F,quote=F

})



        print(x)

*"BIB design Output"*

     [,1] [,2] [,3] [,4]

[1,]    0    1    2    3

[2,]    1    2    3    0

[3,]    3    0    1    2

[4,]    2    3    0    1

vec <- c(as.matrix(x)) # converting matrix into Vector for incidence
correct matrix

                    a=t(x)%*%x

print.matrix <- function(a){



write.table(format(a, justify="right"),



            row.names=F, col.names=F, quote=F)

}



print("X’X ")

        print(a)

A=contrasts( as.factor(x), contrasts =FALSE)[ as.factor(x),]

print.matrix <- function(A){



write.table(format(A, justify="right"),



            row.names=F, col.names=F, quote=F)

}

print("The Incidence Matrix is=")

       print(A)


*OUTPUT*

1 0 0 0

0 1 0 0

0 0 0 1

0 0 1 0

0 1 0 0

0 0 1 0

1 0 0 0

0 0 0 1

0 0 1 0

0 0 0 1

0 1 0 0

1 0 0 0

0 0 0 1

1 0 0 0

0 0 1 0

0 1 0 0


*I need this *

* 1   1  1  1*

* 1   1  1  1*

* 1   1  1  1*

* 1   1  1  1*

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