Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Breakdown points for maximum likelihood estimators of location-scale
  mixtures   ML-estimation based on mixtures of Normal distributions is a widely used tool
for cluster analysis. However, a single outlier can make the parameter
estimation of at least one of the mixture components break down. Among others,
the estimation of mixtures of t-distributions by McLachlan and
  Peel [Finite Mixture Models (2000) Wiley, New York] and the addition of a
further mixture component accounting for ``noise'' by Fraley and Raftery
  [The Computer J. 41 (1998) 578-588] were suggested as more robust
alternatives.
  In this paper, the definition of an adequate robustness measure for cluster
analysis is discussed and bounds for the breakdown points of the mentioned
methods are given. It turns out that the two alternatives, while adding
stability in the presence of outliers of moderate size, do not possess a
substantially better breakdown behavior than estimation based on Normal
mixtures. If the number of clusters s is treated as fixed, r additional points
suffice for all three methods to let the parameters of r clusters explode. Only
in the case of r=s is this not possible for t-mixtures. The ability to estimate
the number of mixture components, for example, by use of the Bayesian
information criterion of Schwarz [Ann. Statist. 6 (1978)
  461-464], and to isolate gross outliers as clusters of one point, is crucial
for an improved breakdown behavior of all three techniques. Furthermore, a
mixture of Normals with an improper uniform distribution is proposed to achieve
more robustness in the case of a fixed number of components.

8
The categories of this paper are: hep-ex
15
The categories of this paper are: nucl-ex
11
The categories of this paper are: hep-lat
9
The categories of this paper are: nlin
22
The categories of this paper are: chao-dyn
37
The categories of this paper are: supr-con
23
The categories of this paper are: solv-int
24
The categories of this paper are: dg-ga
32
The categories of this paper are: atom-ph
28
The categories of this paper are: alg-geom
21
The categories of this paper are: adap-org
13
The categories of this paper are: quant-ph
33
The categories of this paper are: plasm-ph
7
The categories of this paper are: hep-th
30
The categories of this paper are: q-alg
0
The categories of this paper are: hep-ph