Displaying 1 result from an estimated 1 matches for "err_total_chem".
2004 Jul 22
2
Standard error of a sum
...6,54.56,85.05,91.17,90.86)
d.1 <- data.frame(event,chem)
attach(d.1)
s.err <- function(x) sd(x)/(sqrt(length(x)))
print(mean_event <- tapply(d.1$chem,factor(data.1$event),mean))
print(s.err_event <- tapply(d.1$chem,factor(data.1$event),s.err))
print(total_chem <- sum(mean_event))
s.err_total_chem <-
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Jose A. Hernandez
Ph.D. Candidate
Precision Agriculture Center
Department of Soil, Water, and Climate
University of Minnesota
1991 Upper Buford Circle
St. Paul, MN 55108
Ph. (612) 625-0445, Fax. (612) 625-2208