Centre for Discrete and Applicable Mathematics |
|
CDAM Research Report, LSE-CDAM-99-10October 1999 |
Graham R. Brightwell and William T. Trotter
Abstract
In this paper, we initiate a combinatorial approach to proving correlation inequalities for finite partially ordered sets. A new proof is provided for the strong form of the XYZ theorem, due to P.C. Fishburn. We also use our method to give a new proof of a related correlation result of L.A. Shepp involving two sets of relations. Our arguments are entirely combinatorial in the sense that they do not make use of the Ahlswede/Daykin theorem or any of its relatives.
A compressed (gzip) PostScript file (88 kB) with the full contents of this report can be downloaded by clicking here.
Alternatively, if you like a free hard copy of this report, please send the number of this report, LSE-CDAM-99-10, together with your name and postal address to:
CDAM Research Reports Series Centre for Discrete and Applicable Mathematics London School of Economics Houghton Street London WC2A 2AE, U.K. |
||
Phone: +44(0)-171-955 7732. Fax: +44(0)-171-955 6877. Email: info@maths.lse.ac.uk |
Introduction to the CDAM Research Report Series. | ||
CDAM Homepage. |
Last changed: Wed 9 Feb 2005
For comments go to:
http://www.maths.lse.ac.uk/webmaster.html