Domanda

var, sd, cor functions in {stats} use n-1 as a denominator (where n the number of observations). Out of curiosity, are there equivalent function that use n as a denominator?

È stato utile?

Soluzione

Try this:

library(RH2) # needs Java
library(sqldf)

n <- length(BOD$demand)

sd(BOD$demand)
sqrt((n-1)/n) * sd(BOD$demand)
sqldf("select stddev_samp(demand) as samp, stddev_pop(demand) as pop from BOD")

var(BOD$demand)
(n-1)/n * var(BOD$demand)
sqldf("select var_samp(demand) as samp, var_pop(demand) as pop from BOD")    
Autorizzato sotto: CC-BY-SA insieme a attribuzione
Non affiliato a StackOverflow
scroll top