Hello, I have a data set of about 300.000 measurements made by an STM which should apporximately fix a normal (Gaussian) distribution. I have imported the data in R and used plot(density()) to get a nice plot of the distribution which in fact looks like a real Gaussian. However, the integral over the surface is not equal to one (I know since some of the plots extend to numbers greater then 1). Is there a way to normalize the data so the density function will actualy yield the probability of x (a height in my case)? This is my code so far:
#Input path path <- "G:\\C\\Data txt\\1au300.txt" #Dataverwerking data <- read.table(path, header=TRUE) rows <- length(data$height) height <- data$height[1:rows] dens <-density(height) mean <- mean(height) sd <- sd(height) min <- min(hnorm) max <- max(hnorm) #Plot par(new=FALSE) curve(dnorm(x,m=mean,sd=sd),from=min,to=max, xlab="", ylab="", col="white", lwd=2) points(dens, type="h", col="grey" ) par(new=TRUE) curve(dnorm(x,m=mean,sd=sd),from=min,to=max, xlab="Height (nm)", ylab="Density", lwd=2, col="darkred") Thanks [[alternative HTML version deleted]] ______________________________________________ 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.