r:standard_error
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Standard deviation:
plot(seq(-3.2,3.2,length=50),dnorm(seq(-3,3,length=50),0,1),type="l",xlab="",ylab="",ylim=c(0,0.5))
segments(x0 = c(-3,3),y0 = c(-1,-1),x1 = c(-3,3),y1=c(1,1))
text(x=0,y=0.45,labels = expression("99.7% of the data within 3" ~ sigma))
arrows(x0=c(-2,2),y0=c(0.45,0.45),x1=c(-3,3),y1=c(0.45,0.45))
segments(x0 = c(-2,2),y0 = c(-1,-1),x1 = c(-2,2),y1=c(0.4,0.4))
text(x=0,y=0.3,labels = expression("95% of the data within 2" ~ sigma))
arrows(x0=c(-1.5,1.5),y0=c(0.3,0.3),x1=c(-2,2),y1=c(0.3,0.3))
segments(x0 = c(-1,1),y0 = c(-1,-1),x1 = c(-1,1),y1=c(0.25,0.25))
text(x=0,y=0.15,labels = expression("68% of the data within 1" * sigma),cex=0.9)
see this blog for about layout of figures
par(mfrow=c(2,2)) x1 <- rnorm(100) x2 <- rnorm(1000) x3 <- rnorm(10000) x4 <- rnorm(100000) hist(x1) hist(x2) hist(x3) hist(x4) par(mfrow=c(1,1))
x <- norm(1000, mean=0, sd=10) sex4 <- sd(x) / sqrt(length(4)) sex25 <- sd(x) / sqrt(length(25)) sex100 <- sd(x) / sqrt(length(100)) sex900 <- sd(x) / sqrt(length(900)) sex1600 <- sd(x) / sqrt(length(1600)) sex4 sex25 sex100 sex900 sex1600
r/standard_error.1505347729.txt.gz · Last modified: 2017/09/14 08:38 by hkimscil