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Create a fitted loadLm object.

Source: R/loadLm.R
loadLm.Rd

Generates a new model of class loadInterp (loadLm-class) which can connect observations of concentration or flux using a linear regression model.

Usage

loadLm(
  formula,
  pred.format = c("flux", "conc"),
  data,
  metadata,
  fitting_function = NULL,
  y.trans.function = NULL,
  retrans.function = exp,
  store = c("data", "fitting.function"),
  ylog
)

Arguments

formula

A formula specifying the linear model to fit.

pred.format

In what format (flux or conc) does the lm object make predictions when predict.lm() is called?

data

data.frame. The data to be interpolated

metadata

metadata, used to access the appropriate columns of data. At a minimum, metadata should correctly specify the date column.

fitting_function

a fitting function that can produce a new loadComp object from new data (this currently uses the same new data for both regression calibration and interpolation)

y.trans.function

function that accepts a vector of predictions straight from the fitted model and retransforms them, if appropriate, to predictions in linear space and with units of concentration*flow. Because load models are frequently fit to log(y) ~ ..., the default is retrans.function=exp. After retrans.function has been applied to the predictions, the retransformed predictions will automatically undergo further units conversion from conc*flow to load.rate, according to the metadata elements conc.units, flow.units, and load.rate.units.

retrans.function

function that accepts a vector of predictions straight from the fitted model and retransforms them, if appropriate, to predictions in linear space and with units of concentration*flow. Because load models are frequently fit to log(y) ~ ..., the default is retrans.function=exp. After retrans.function has been applied to the predictions, the retransformed predictions will automatically undergo further units conversion from conc*flow to load.rate, according to the metadata elements conc.units, flow.units, and load.rate.units.

store

One or more character strings specifying which information to write within the model. Options are 'data': the original fitting data; 'fitting.function': a fitting function that can produce a new loadComp object from new data

ylog

logical. If TRUE, this constitutes affirmation that the values passed to the left-hand side of the model formula will be in log space. If missing, the value of ylog will be inferred from the values of formula and y.trans.function, but be warned that this inference is fallible.

Value

A fitted loadLm model.

See also

Other load.model.inits: loadComp(), loadInterp(), loadModel(), loadReg2()

Examples

data(eg_fitdat, eg_metadata)
no3_lm <- loadLm(formula=log(NO3) ~ log(DISCHARGE) + DATE, pred.format="conc",
  data=eg_fitdat, metadata=eg_metadata, retrans=exp)