determiningLambda: Method "determiningLambda"
In PhenStat: Statistical analysis of phenotypic data

Description Usage Arguments Value Author(s) Examples

Function role 1. Rescale data if needed (Box-Cox transformation can only be applied on data >0) 2. Calculate lambda value for a Box-Cox transformation 3. Assess whether transformation is required (if confidence interval includes 1 then no transformation required) 4. Return output to allow application of the transformation if necessary using the returned lambda value and any associated rescaling that was needed. 5. Requires a function that will be fitted determined from formulaAssessingBoxCox

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    determiningLambda(phenList, 
					depVariable, 
					equation="withWeight")

`phenList`	instance of the `PhenList` class; mandatory argument
`depVariable`	a character string defining the dependent variable of interest; mandatory argument
`equation`	a character string defining the equation to use. Possible values "withWeight" (default),"withoutWeight"

Returns a vector with five elements: 1. 95 2. Midepoint of the 95 3. Calculated lambda value 4. TransformationRequired: TRUE/FALSE 5. Calculated scale shift value

Natasha Karp

        file <- system.file("extdata", "test1.csv", package="PhenStat")
        test <- PhenStat:::PhenList(dataset=read.csv(file,na.strings = '-'),
                testGenotype="Sparc/Sparc")
        PhenStat:::determiningLambda(test,"Lean.Mass",equation="withoutWeight")