drLM: LM Transformation Method
In datadr: Divide and Recombine for Large, Complex Data

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

LM transformation method – – Fit a linear model to each subset

drLM(...)

...

arguments you would pass to the lm function

This provides a transformation function to be called for each subset in a recombination MapReduce job that applies R's lm method and outputs the coefficients in a way that combMeanCoef knows how to deal with. It can be applied to a ddf with addTransform prior to calling recombine.

An object of class drCoef that contains the lm coefficients and other data needed by combMeanCoef

Landon Sego

divide, recombine, rrDiv

# Divide the data
bySpecies <- divide(iris, by = "Species")

# A function to fit a multiple linear regression model to each species
linearReg <- function(x)
  drLM(Sepal.Length ~ Sepal.Width + Petal.Length + Petal.Width,
       data = x)

# Apply the transform and combine using 'combMeanCoef'
bySpecies %>%
  addTransform(linearReg) %>%
  recombine(combMeanCoef)