Hi, Looks like the function "theta" takes a variable "data", but that variable is not being used in the body of the function (you are using the global dataX and dataY, which will be the same each time the function is called).
Martyn -----Original Message----- From: r-help-boun...@r-project.org [mailto:r-help-boun...@r-project.org] On Behalf Of ufuk beyaztas Sent: 17 January 2011 13:21 To: r-help@r-project.org Subject: [R] Problem about for loop Hi everyones, my function like; e <- rnorm(n=50, mean=0, sd=sqrt(0.5625)) x0 <- c(rep(1,50)) x1 <- rnorm(n=50,mean=2,sd=1) x2 <- rnorm(n=50,mean=2,sd=1) x3 <- rnorm(n=50,mean=2,sd=1) x4 <- rnorm(n=50,mean=2,sd=1) y <- 1+ 2*x1+4*x2+3*x3+2*x4+e x2[1] = 10 #influential observarion y[1] = 10 #influential observarion data.x <- matrix(c(x0,x1,x2,x3,x4),ncol=5) data.y <- matrix(y,ncol=1) data.k <- cbind(data.x,data.y) dataX <- data.k[,1:5] dataY <- data.k[,6] theta <- function(data) { B.cap <- solve(crossprod(dataX)) %*% crossprod(dataX,dataY) P <- dataX %*% solve(crossprod(dataX)) %*% t(dataX) Y.cap <- P %*% dataY e <- dataY - Y.cap dX <- nrow(dataX) - ncol(dataX) var.cap <- crossprod(e) / (dX) ei <- as.vector(dataY - dataX %*% B.cap) pi <- diag(P) var.cap.i <- (((dX) * var.cap) / (dX - 1)) - (ei^2 / ((dX-1) * (1 - pi))) ti <- ei / sqrt(var.cap * (1 - pi)) Ci <- (ti^2 / (ncol(dataX))) * (pi / (1 - pi)) output.i <- mean(Ci)} result <- list() for ( i in 1:5){ data <- replicate(1, data.k[sample(50,50,replace=T),], simplify = FALSE) output.j <- theta(data) result <- c(result,(list(output.j))) } table <- do.call(rbind.data.frame,result) names(table)=c("cooks") table This function give same results each time, the data is changing every time but mean(Ci)s are always same. Does anyone have an idea about how to be? Thanks for any idea -- View this message in context: http://r.789695.n4.nabble.com/Problem-about-for-loop-tp3221210p3221210.h tml Sent from the R help mailing list archive at Nabble.com. ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code. ________________________________________________________________________ This e-mail has been scanned for all viruses by Star.\ _...{{dropped:12}} ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
