otpospoisUC: One-truncated Positive-Poisson Distribution

OtpospoisR Documentation

One-truncated Positive-Poisson Distribution


Density, distribution function, quantile function, and random generation for the one-truncated positive-Poisson distribution.


dotpospois(x, lambda, log = FALSE)
potpospois(q, lambda, log.p = FALSE)
qotpospois(p, lambda)
rotpospois(n, lambda)


x, q, p, n

Same as Pospois.

lambda, log, log.p

Same as Pospois.


The one-truncated positive-Poisson is a Poisson distribution but with the probability of a one and a zero being 0. That is, its support is 2, 3, .... The other probabilities are scaled to add to unity. Some more details are given in pospoisson.


dotpospois gives the density, potpospois gives the distribution function, qotpospois gives the quantile function, and rotpospois generates random deviates.


Given some response data, the VGAM family function otpospoisson estimates the parameter lambda.


T. W. Yee

See Also

otpospoisson, Pospois, Oipospois.


dotpospois(1:20, 0.5)
rotpospois(20, 0.5)

## Not run:  lambda <- 4; x <- 1:10
plot(x, dotpospois(x, lambda = lambda), type = "h", ylim = 0:1,
     sub = "lambda=4", las = 1, col = "blue", ylab = "Probability",
     main = "1-truncated positive-Poisson distn: blue=PMF; orange=CDF")
lines(x+0.1, potpospois(x, lambda), col = "orange", lty=3, type = "h") 
## End(Not run)

VGAMdata documentation built on Sept. 18, 2023, 9:08 a.m.