# otpospoisson: One-truncated Poisson Distribution In VGAMdata: Data Supporting the 'VGAM' Package

 otpospoisson R Documentation

## One-truncated Poisson Distribution

### Description

Estimating the (single) parameter of the 1-truncated positive Poisson distribution.

### Usage

``` otpospoisson(llambda = "loglink",
type.fitted = c("mean", "lambda", "prob0", "prob1"),
ilambda = NULL, imethod = 1, zero = NULL)
```

### Arguments

 `llambda, type.fitted, ilambda` Same as `pospoisson`. `imethod, zero` Same as `pospoisson`.

### Details

The 1-truncated positive Poisson distribution has support on 2, 3, .... It is a Poisson distribution but with the probability of a one or zero being 0. The other probabilities are scaled to add to unity. Some more details can be found at `pospoisson`. Multiple responses are permitted.

### Value

An object of class `"vglmff"` (see `vglmff-class`). The object is used by modelling functions such as `vglm`, and `vgam`.

### Author(s)

T. W. Yee

`Otpospois`, `oipospoisson`, `simulate.vlm`.

### Examples

```## Not run:
odata <- data.frame(y1 = rotpospois(n = 1000, lambda = loglink(1, inverse = TRUE)))
ofit <- vglm(y1 ~ 1, otpospoisson, data = odata, trace = TRUE, crit = "c")
coef(ofit, matrix = TRUE)
Coef(ofit)
with(odata,
hist(y1, prob = TRUE, breaks = seq(0.5, max(y1) + 0.5, by = 1),
border = "blue"))
x <- seq(1, with(odata, max(y1)), by = 1)
with(odata, lines(x, dotpospois(x, Coef(ofit)[1]), col = "orange", type = "h", lwd = 2))
## End(Not run)
```

VGAMdata documentation built on March 18, 2022, 8:03 p.m.