Description Usage Arguments Details Value Note Author(s) See Also Examples

'W1.3' and `W2.3`

provide the three-parameter Weibull function, self starter function and names of the parameters.

'W1.3u' and 'W2.3u' provide three-parameter Weibull function where the upper limit is equal to 1, mainly for use with binomial/quantal response.

1 2 3 4 5 6 7 8 9 | ```
W1.3(fixed = c(NA, NA, NA), names = c("b", "d", "e"), ...)
W2.3(fixed = c(NA, NA, NA), names = c("b", "d", "e"), ...)
W2x.3(fixed = c(NA, NA, NA), names = c("d", "e", "t0"), ...)
W1.3u(upper = 1, fixed = c(NA, NA, NA), names = c("b", "c", "e"), ...)
W2.3u(upper = 1, fixed = c(NA, NA, NA), names = c("b", "c", "e"), ...)
``` |

`upper` |
numeric value. The fixed, upper limit in the model. Default is 1. |

`fixed` |
numeric vector. Specifies which parameters are fixed and at what value they are fixed. NAs for parameter that are not fixed. |

`names` |
a vector of character strings giving the names of the parameters. The default is reasonable. |

`...` |
additional arguments to be passed from the convenience functions. |

The three-parameter Weibull model is given by the expression

* f(x) = 0 + (d-0)\exp(-\exp(b(\log(x)-e))).*

The function is asymmetric about the inflection point, that is the parameter *\exp(e)*.

The three-parameter Weibull model with upper limit 1 is given by the expression

* f(x) = 0 + (1-0)\exp(-\exp(b(\log(x)-e))).*

See `weibull1`

.

This function is for use with the function `drm`

.

Christian Ritz

Related functions are `W1.4`

and `weibull1`

.

1 2 3 |

drc documentation built on May 29, 2017, 11:31 a.m.

Embedding an R snippet on your website

Add the following code to your website.

For more information on customizing the embed code, read Embedding Snippets.