mix_predict: Make predictions for all species in a dataset using linear...

In xp-song/allometree: Allometric Scaling of Urban Trees

Make predictions for all species in a dataset using linear mixed-effects model

Description

Make predictions across rows in a dataset that may contain multiple species. The mixed-effects model is used to predict values for the response variable, as well as it's prediction interval. Necessary bias-corrections are made if the mixed-effects model has a transformed response variable.

Usage

mix_predict(
  data,
  modelselect,
  level = 0.95,
  stat = "median",
  n.sims = 1000,
  predictor = "diameter",
  species = "species",
  ...
)

Arguments

data	Dataframe with columns containing the species and variables of interest. Each row is a measurement for an individual tree.
modelselect	Output from the mix_modelselect() function.
level	Level of confidence for the prediction interval. Defaults to 0.95.
stat	Specify whether the "median" or "mean" of simulated intervals are used.
n.sims	Number of bootstrapped simulations to generate the prediction intervals. Defaults to 1000.
predictor	Column name of the predictor variable in data. Defaults to diameter.
species	Column name of the species variable in data. Defaults to species.
...	Additional arguments passed to merTools::predictInterval()

Value

Dataframe of input data with columns appended:

fit

Predicted value for the response variable.

lwr

Lower bound of the prediction interval, based on the input argument level.

upr

Upper bound of the prediction interval, based on the input argument level.

See Also

merTools::predictInterval() to make predictions from models fit with the lme4 package.

Other mixed-effects model functions: mix_modelselect(), mix_simulate()

Examples

data(urbantrees)

## Not run: 
model <- mix_modelselect(urbantrees)

Alb_sam <- urbantrees[urbantrees$species == 'Albizia saman', ]  # use one species as an example
results <- mix_predict(data = Alb_sam, modelselect = model,
                       predictor = "diameter") # make predictions for measured values

head(results)

## End(Not run)

xp-song/allometree documentation built on March 28, 2022, 4:36 a.m.