ggformula: geom_lm – R documentation

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geom_lm

Linear Model Displays

Description

Adds linear model fits to plots. geom_lm() and stat_lm() are essentially equivalent. Use geom_lm() unless you want a non-standard geom.

Usage

stat_lm(
  mapping = NULL,
  data = NULL,
  geom = "lm",
  position = "identity",
  interval = c("none", "prediction", "confidence"),
  level = 0.95,
  formula = y ~ x,
  lm.args = list(),
  backtrans = identity,
  ...,
  na.rm = FALSE,
  show.legend = NA,
  inherit.aes = TRUE
)

geom_lm(
  mapping = NULL,
  data = NULL,
  stat = "lm",
  position = "identity",
  interval = c("none", "prediction", "confidence"),
  level = 0.95,
  formula = y ~ x,
  lm.args = list(),
  backtrans = identity,
  ...,
  na.rm = FALSE,
  show.legend = NA,
  inherit.aes = TRUE
)

Arguments

`mapping`	Set of aesthetic mappings created by `aes()` or `aes_()`. If specified and `inherit.aes = TRUE` (the default), it is combined with the default mapping at the top level of the plot. You must supply `mapping` if there is no plot mapping.
`data`	The data to be displayed in this layer. There are three options: If `NULL`, the default, the data is inherited from the plot data as specified in the call to `ggplot()`. A `data.frame`, or other object, will override the plot data. All objects will be fortified to produce a data frame. See `fortify()` for which variables will be created. A `function` will be called with a single argument, the plot data. The return value must be a `data.frame`, and will be used as the layer data. A `function` can be created from a `formula` (e.g. `~ head(.x, 10)`).
`geom, stat`	Use to override the default connection between `geom_lm` and `stat_lm`.
`position`	Position adjustment, either as a string, or the result of a call to a position adjustment function.
`interval`	One of `"none"`, `"confidence"` or `"prediction"`.
`level`	The level used for confidence or prediction intervals
`formula`	a formula describing the model in terms of `y` (response) and `x` (predictor).
`lm.args`	A list of arguments supplied to `lm()` when performing the fit.
`backtrans`	a function that transforms the response back to the original scale when the `formula` includes a transformation on `y`.
`...`	Other arguments passed on to `layer()`. These are often aesthetics, used to set an aesthetic to a fixed value, like `colour = "red"` or `size = 3`. They may also be parameters to the paired geom/stat.
`na.rm`	If `FALSE`, the default, missing values are removed with a warning. If `TRUE`, missing values are silently removed.
`show.legend`	logical. Should this layer be included in the legends? `NA`, the default, includes if any aesthetics are mapped. `FALSE` never includes, and `TRUE` always includes. It can also be a named logical vector to finely select the aesthetics to display.
`inherit.aes`	If `FALSE`, overrides the default aesthetics, rather than combining with them. This is most useful for helper functions that define both data and aesthetics and shouldn't inherit behaviour from the default plot specification, e.g. `borders()`.

Details

Stat calculation is performed by the (currently undocumented) predictdf. Pointwise confidence or prediction bands are calculated using the predict() method.

Examples

ggplot(data = mosaicData::KidsFeet, aes(y = length, x = width, color = sex)) +
  geom_lm() +
  geom_point()
ggplot(data = mosaicData::KidsFeet, aes(y = length, x = width, color = sex)) +
  geom_lm(interval = "prediction", color = "skyblue") +
  geom_lm(interval = "confidence") +
  geom_point() +
  facet_wrap(~sex)
# non-standard display
ggplot(data = mosaicData::KidsFeet, aes(y = length, x = width, color = sex)) +
  stat_lm(aes(fill = sex),
    color = NA, interval = "confidence", geom = "ribbon",
    alpha = 0.2
  ) +
  geom_point() +
  facet_wrap(~sex)
ggplot(mpg, aes(displ, hwy)) +
  geom_lm(
    formula = log(y) ~ poly(x, 3), backtrans = exp,
    interval = "prediction", fill = "skyblue"
  ) +
  geom_lm(
    formula = log(y) ~ poly(x, 3), backtrans = exp, interval = "confidence",
    color = "red"
  ) +
  geom_point()

ggformula

Formula Interface to the Grammar of Graphics

v0.10.1

MIT + file LICENSE

Authors

Daniel Kaplan [aut], Randall Pruim [aut, cre]

Initial release