Displaying 1 result from an estimated 1 matches for "j2g".
Did you mean:
2g
2009 Jul 13
0
Anomaly in sample() function
...I have computed the mean difference and the SD of the relative
frequencies between sample and pop. What mean deviation is to expect?
Thanks for any ideas,
W. Polasek
dimnames(g99)[[1]] =paste(g99[,1])
s1= g99[paste(sample(g99[,1], 100, F, g99[,4])),1:4]
dim(s1)
j2 =table(s1[,3]) #sample density
j2g= table(g99[,3]) #pop density
chisq.test(j2g,j2)
p2=100*j2g / sum(j2g) #rel. frequency in pop
pd=p2-100* j2/sum(j2) #difference of rel. frequency between pop and sample
round(rbind(j2g, p2, pd),2)
sum(abs(pd));sd(pd) #look for the 'best' representative sample