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rr-carprobability-distribution

Fitting Binomial distribution with car package

For fitting several probability distribution for my data set, I try several distributions using car and MASS packages, for example for Poisson distribution:

require(car); require (MASS)

#Data set
X1 <- rnorm(100, 175, 7)
Y1 <- rbinom(100,1, 0.35)
##Fitting Poisson:
poisson <- fitdistr(Y1, "Poisson")
qqp(Y1, "pois", poisson$estimate)

But, If my option is Binomial distribution, MASS package don't support this kind of distribution, then I use fitdistrplus package:

require(fitdistrplus)
fitBinom=fitdist(data=Y1, dist="binom", fix.arg=list(size=100), start=list(prob=0.35))

When I try:

qqp(Y1, "Binomial", fitBinom$estimate)

Doesn't work the qqp function of car package. There are other options for fitting Binomial distribution like qqp function?

Thanks,

Solution

  • qqp actually works with fitdistrplus. You only need to add all parameters for Binomial distribution. You also need to replace "Binomial" with "binom"

    fitBinom <- fitdist(data=Y1, dist="binom", fix.arg=list(size=100), start=list(prob=0.35))
qqp(Y1, "binom", size=100, fitBinom$estimate)