Check if the values of parameters are valid. See the reference for details.
testpar(mixpar, dist, constr)a data frame containing the values for parameters of component distributions, which are, in order, the proportions, means, and standard deviations.
the distribution of components, it can be one of
"norm", "lnorm", "gamma", "weibull",
"binom", "nbinom" and "pois".
a list of constraints on parameters of component
distributions. See function mixconstr.
logical. If TRUE, the parameters are valid. If FALSE,
some of the parameters are invalid. Since this function is for
internal use, it doesn't give error messages.
Any of the parameter values can not be missing value (NA
or NaN) or infinity (Inf), and the proportions
can only take the values between 0 and 1. Besides, the
standard deviations can not be negative. The components
must be indexed so that the means are in non-decreasing
order. If any two consecutive means are equal, then the
corresponding standard deviations must be in strictly
ascending order. Furthermore, the parameter values should
be consistent with the constraints and the distribution
of components. For example, if one wants to constrain
the means to lie along a growth curve, then (\(\mu_3\) - \(\mu_2\)) <
(\(\mu_2\) - \(\mu_1\)) is required. Also, negative means are not permitted by
the constraints "FCV", "CCV", "BINOM", "NBINOM",
"POIS" and all the distributions but Normal. If the
Binomial distribution components with the constraint "BINOM"
are fitted, then the relation \(\mu_i\) > \((\sigma_i)^2\) need to be
satisfied. And the Negative Binomial components with the
constraint "NBINOM" require \(\mu_i\) < \((\sigma_i)^2\).
Macdonald, P.D.M. and Green, P.E.J. (1988) User's Guide to Program MIX: An Interactive Program for Fitting Mixtures of Distributions. ICHTHUS DATA SYSTEMS.
mixparam for organizing the parameter values,
mixconstr for constructing constraints, testconstr
for checking constraints.