Probitw: Calculate weighting coefficient from expected probit

In ecotoxicology: Methods for Ecotoxicology

Description

Returns the weighting coefficient from expected probit

Usage

Probitw(Y, C = 0)

Arguments

Y	numeric, expected probit
C	numeric, proportion of natural mortality

Value

the weighting coefficient

Author(s)

Jose Gama

References

Finney D. J., 1964 Probit analysis: a statistical treatment of the sigmoid response curve. Cambridge University Press. Formula 6.3.

Examples

# Example from page 90 of Finney 1964:
# expected probit Y = 6.2, control mortality C = 59%
Y <- 6.2
C <- 0.59
# weighting coefficient = 0.141
Probitw(Y,C)

Example output

[1] 0.1410092

ecotoxicology documentation built on May 2, 2019, 11:34 a.m.