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expirest (version 0.1.6)

get_icpt: Getting the intercept(s) of a linear model

Description

The function get_icpt() determines the intercept(s) of the provided model.

Usage

get_icpt(
  model,
  response_vbl,
  time_vbl,
  batch_vbl,
  xform = c("no", "no"),
  shift = c(0, 0)
)

Value

A list with a single element containing the numeric value or a numeric vector of the intercept(s) or, if the data have been transformed, a list with an additional element that contains the numeric value or numeric vector on the original scale is returned.

Arguments

model

A linear model object of type ‘lm’.

response_vbl

A character string that specifies the response variable name that must be a column of the data frame that was used for model fitting.

time_vbl

A character string that specifies the time variable name that must be a column of data frame that was used for model fitting.

batch_vbl

A character string that specifies the column of the data frame that was used for model fitting with the grouping information (i.e. a categorical variable) for the differentiation of the observations from the different batches.

xform

A vector of two character strings that specifies the transformation of the response and the time variable. The default is “no” transformation, i.e. c("no", "no"), where the first element specifies the transformation of the \(x\) variable and the second element the transformation of the \(y\) variable. Valid alternatives for \(x\) and/or \(y\) variable transformation are "log" (natural logarithm), "sqrt" (square root) and "sq" (square).

shift

A vector of two values which will be added to the variables \(x\) and/or \(y\) before they are transformed as specified by the xform parameter, where the first element will be added to the \(x\) variable and the second element to the \(y\) variable. The purpose is to prevent an undefined state which could arise when variables with values of \(\leq 0\) are log or square root transformed. The default is c(0, 0).

Details

The function get_icpt() determines the intercept(s) of the model that has been handed over via the model parameter.

See Also

get_icpt_list, expirest_osle, expirest_wisle, lm.