correctval function

Predict the Corrected Proportional Effect

Given an expected proportional effect, calculate the "corrected" proportional effect using a model fit of Litchfield and Wilcoxon's (1949) Table 1.

correctval(val, fit)

Arguments

• val: A numeric vector of expected effects (as proportions).
• fit: A model object to be used to predict the "corrected" effects (as proportions) from distexpprop5, the distance between the expected effects (as proportions) and 0.5. Typically the output from gamtable1().

Returns

A numeric vector of corrected effects (as proportions), the same length as val.

Examples

gamfit <- gamtable1()
correctval(c(0.37, 0.5, 0.63), gamfit)

References

Litchfield, JT Jr. and F Wilcoxon. 1949. A simplified method of evaluating dose-effect experiments. Journal of Pharmacology and Experimental Therapeutics 96(2):99-113. [link].