R: List of lm objects with a common model

by-lmby {doBy} | R Documentation

## List of lm objects with a common model

### Description

The data is split into strata according to the levels of the grouping factors and individual lm fits are obtained for each stratum.

### Usage

    lmBy(formula, data, id = NULL, ...)

### Arguments

`formula` | A linear model formula object of the form y ~ x1 + ... + xn | g1 + ... + gm. In the formula object, y represents the response, x1,...,xn the covariates, and the grouping factors specifying the partitioning of the data according to which different lm fits should be performed.
`data` | A dataframe
`id` | A formula describing variables from data which are to be available also in the output.
`...` | Additional arguments passed on to `lm()`.

### Value

A list of lm fits.

### Author(s)

Søren Højsgaard, sorenh@math.aau.dk

### Examples

    bb <- lmBy(1 / uptake ~ log(conc) | Treatment, data=CO2)

    coef(bb)

    fitted(bb)
    residuals(bb)

    summary(bb)
    coef(summary(bb))
    coef(summary(bb), simplify=TRUE)

    ## A more modern alternative based on tidyverse end broom

    ## if (require(tidyverse) && require(broom)){
    ##  gg <- CO2 %>% group_by(Treatment)
    ##  gg %>% do(broom::tidy(lm(1 / uptake ~ log(conc), data=.)))
    ##}

[Package doBy version 4.6.5 Index]