How about ....

# Read Data

nb10 <- read.table("http://www.adjoint-functors.net/su/web/314/R/NB10")

# Calculate Stats

total = length(nb10[,1])

mean = mean(nb10[,1])

sd = sd(nb10[,1])

# Function ... nSD is the number of SD you are looking at

pData <- function(nSD){

lo = mean - nSD/2*sd

hi = mean + nSD/2*sd

percent = sum(nb10[,1]>=lo & nb10[,1]<=hi)/total *100

}

# Output ...

print(paste("Percent of data within 2 SD is ",pData(2),"%", sep="")) # 86%

print(paste("Percent of data within 3 SD is ",pData(3),"%", sep="")) # 93%

print(paste("Percent of data within 4 SD is ",pData(4),"%", sep="")) # 96%

print(paste("Percent of data within 5 SD is ",pData(5),"%", sep="")) # 97%

print(paste("Percent of data within 6 SD is ",pData(6),"%", sep="")) # 98%

HTH

Pete

Ajata Paul wrote

How do you calculate the percentage of data within 2SD, 3SD, 4SD, 5SD, and

6SD of the mean? I used the following link as the data I'm working with:

nb10 <- read.table("http://www.adjoint-functors.net/su/web/314/R/NB10") if

this helps answer my question. Can you please explain how to calculate

the SD's? Please be specific in which part of the function changes when

calculating the next SD up.

Thanks.

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