lambda = 4
phi = 0.8
(i = dzipois(0:7, lambda, phi))
cumsum(i) - pzipois(0:7, lambda, phi) # Should be 0s
table(rzipois(100, lambda, phi))
table(qzipois(runif(100), lambda, phi))
round(dzipois(0:10, lambda, phi) * 100) # Should be similar
x = 0:10
plot(x, dzipois(x, lambda, phi), type="h", ylab="Probability",
main=paste("ZIP(", lambda, ", phi=", phi, ") (blue) vs",
" Poisson(", lambda, ") (red & shifted slightly)", sep=""),
lwd=2, col="blue", las=1)
lines(x+0.05, dpois(x, lambda), type="h", lwd=2, col="red")
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