stepPlot {mixreg} | R Documentation |
Fit a mixture of regressions model, one EM step at a time, plotting the result after each step.
stepPlot(fmla, ncomp = NULL, eqVar = FALSE, thetaStart = NULL, nsteps = 100, eps = 1e-06, digits = 7, maxTry = 5, seed = NULL, data)
fmla |
The formula specifying the regression in the mixture model that is to be fitted. |
ncomp |
Integer scalar; the number of components in the model. Defaults to 2. |
eqVar |
See |
thetaStart |
See |
nsteps |
Integer scalar; the maximum number of EM steps to be undertaken. |
eps |
See |
digits |
The number of digits to which the details about the EM steps are printed out. |
maxTry |
See |
seed |
See |
data |
A data frame containing the variables to which the model is to be fitted. |
Can only be used in an interactive session. May give some insight into convergence problems or into the reasons for unexpected results in the fit.
An object of class "mixreg"
. See mixreg()
.
The model being fitted may not have converged.
Rolf Turner r.turner@auckland.ac.nz
See mixreg()
.
mixreg()
.
## Not run: # Interactive session is required. vfit <- visualFit(y~x,data=kilnAfull,ncomp=3) stepPlot(y ~ x,ncomp=3,data=kilnAfull,thetaStart=vfit$theta) ## End(Not run) # The result is clearly slightly wrong in respect of the second ("middle") # component, which has a slope that is too low. The outlier in # kilnAfull may be "pulling up" the left hand end of the fitted line.