Learn R Programming
rtemis (version 0.79)

s.NLA: NonLinear Activation unit Regression (NLA) [R]

Description

Train an equivalent of a 1 hidden unit neural network with a defined nonlinear activation function using optim

Usage

s.NLA(x, y = NULL, x.test = NULL, y.test = NULL,
  activation = softplus, b_o = mean(y), W_o = 1, b_h = 0,
  W_h = 0.01, optim.method = "BFGS", control = list(),
  lower = -Inf, upper = Inf, x.name = NULL, y.name = NULL,
  save.func = TRUE, print.plot = TRUE, plot.fitted = NULL,
  plot.predicted = NULL, plot.theme = getOption("rt.fit.theme",
  "lightgrid"), question = NULL, rtclass = NULL, verbose = TRUE,
  trace = 0, outdir = NULL, save.mod = ifelse(!is.null(outdir), TRUE,
  FALSE), ...)

Arguments

x

Numeric vector or matrix / data frame of features i.e. independent variables

y

Numeric vector of outcome, i.e. dependent variable

x.test

Numeric vector or matrix / data frame of testing set features Columns must correspond to columns in x

y.test

Numeric vector of testing set outcome

activation

Function: Activation function to use. Default = softplus

b_o

Float, vector (length y): Output bias. Defaults to mean(y)

W_o

Float: Output weight. Defaults to 1

b_h

Float: Hidden layer bias. Defaults to 0

W_h

Float, vector (length NCOL(x)): Hidden layer weights. Defaults to 0

optim.method

String: Optimization method to use: "Nelder-Mead", "BFGS", "CG", "L-BFGS-B", "SANN", "Brent". See stats::optim for more details. Default = "BFGS"

x.name

Character: Name for feature set

y.name

Character: Name for outcome

print.plot

Logical: if TRUE, produce plot using mplot3 Takes precedence over plot.fitted and plot.predicted

plot.fitted

Logical: if TRUE, plot True (y) vs Fitted

plot.predicted

Logical: if TRUE, plot True (y.test) vs Predicted. Requires x.test and y.test

plot.theme

String: "zero", "dark", "box", "darkbox"

question

String: the question you are attempting to answer with this model, in plain language.

rtclass

String: Class type to use. "S3", "S4", "RC", "R6"

verbose

Logical: If TRUE, print summary to screen.

trace

Integer: If higher than 0, will print more information to the console. Default = 0

outdir

Path to output directory. If defined, will save Predicted vs. True plot, if available, as well as full model output, if save.mod is TRUE

save.mod

Logical. If TRUE, save all output as RDS file in outdir save.mod is TRUE by default if an outdir is defined. If set to TRUE, and no outdir is defined, outdir defaults to paste0("./s.", mod.name)

...

Additional arguments to be passed to sigreg

Value

Object of class rtemis

Details

Since we are using optim, results will be sensitive to the combination of optimizer method (See optim::method for details), initialization values, and activation function.

See Also

elevate for external cross-validation

Other Supervised Learning: s.ADABOOST, s.ADDTREE, s.BART, s.BAYESGLM, s.BRUTO, s.C50, s.CART, s.CTREE, s.DA, s.ET, s.EVTREE, s.GAM.default, s.GAM.formula, s.GAMSEL, s.GAM, s.GBM3, s.GBM, s.GLMNET, s.GLM, s.GLS, s.H2ODL, s.H2OGBM, s.H2ORF, s.IRF, s.KNN, s.LDA, s.LM, s.MARS, s.MLRF, s.MXN, s.NBAYES, s.NLS, s.NW, s.POLYMARS, s.PPR, s.PPTREE, s.QDA, s.QRNN, s.RANGER, s.RFSRC, s.RF, s.SGD, s.SPLS, s.SVM, s.TFN, s.XGBLIN, s.XGB