.boundary.method: Boundary Methods for Population Proportions
Description
Methods used in EM Algorithms to deal with boundary problems of
population proportions, \(\eta_k\).
The first element is the default value.
This is a read-only object and the elemental order is followed in C.
Usage
.boundary.method
Arguments
Format
A character vector contains implemented boundary methods in C.
The boundary value 0 of the population proportions makes the log
likelihood as -Inf. Since degeneracy of subpopulations can affect
the maximizing processes in EM steps. This problem is usually caused
by bad initializations, and may suggest that number of cluster
\(K\) may be too large.
Two methods have been implemented when any \(\eta_k\) less than
the lower bound (\(1/N\) or \(1e-16\)).
The ADJUST (default) will adjust the \(\eta_k\) to the
lower bound, and the IGNORE will stop the iterations and return
errors.