| Title |
Inverse correspondence analysis |
| Author |
Groenen, P.J.F. (Patrick); Velden, van de M. (Michel) |
| Date |
2002-09-20 |
| Language |
English |
| Type |
working paper |
| Abstract |
In correspondence analysis, rows and columns of a data matrix are depicted as points in
low-dimensional space. The row and column profiles are approximated by minimizing the
so-called weighted chi squared distance between the original profiles and their
approximations, see or example, Greenacre (1984). In this paper, we will study the
inverse correspondence analysis solution. We will show that there exists a nonempty
closed and bounded polyhedron of such matrices. We also present an algorithm to find
the vertices of the polyhedron. A proof that the maximum of the Pearson chi-squared
statistic is attained at one of the vertices is given. In addition, it is discussed
how extra equality constraints on some elements of the data matrix can be imposed on
the inverse correspondence analysis problem. As a special case, we present a method for
imposing integer restrictions on the data matrix as well. The approach to inverse
correspondence analysis followed here is similar to the one employed by De Leeuw and
Groenen (1997) in their inverse multidimensional scaling problem. |
| Publication |
http://hdl.handle.net/1765/550 |
| Persistent Identifier |
urn:NBN:nl:ui:15-1765/550 |
| Metadata |
XML |
| Repository |
Erasmus University Rotterdam |