DIMACS Technical Report 2006 - 06 December 2006 Generalized Traffic Equations

Lattices with Few Distances*

The n-dimensional lattices that contain fewest distances are characterized for all n ≠ 2. ___________* This paper appeared in J. Number Theory, 39 (1991), 75-90. It is also DIMACS Technical Report 90-77,December 1990.

Hilbert's Nullstellensatz Is in the Polynomial Hierarchy

We show that if the Generalized Riemann Hypothesis is true, the problem of deciding whether a system of polynomial equations in several complex variables has a solution is in the second level of the polynomial hierarchy. In fact, this problem is in AM, the \Arthur-Merlin" class (recall that NP AM RPNP 2). The best previous bound was PSPACE. An earlier version of this paper was distributed as Ne...

Technical Report Series COMPARISON OF FOUR SMALL SAMPLE BIAS CORRECTIONS OF THE EMPIRICAL COVARIANCE ESTIMATORS

The empirical (sandwich or robust) covariance matrix, usually used in conjunction with Generalized Estimating Equations (GEE) and Generalized Linear Mixed Models (GLMM), is biased towards zero for small sample sizes. As a consequence of this bias Type I error rates are usually higher than the nominal levels. Several small sample bias corrections have been proposed in the literature. The purpose...

Oriented k-windows: A PCA driven clustering method

Technical Report HPCLAB-SCG 2/02-06 (revised 3/06) LABORATORY: High Performance Information Systems Laboratory GRANTS: University of Patras “Karatheodori” Grant; Bodossaki Foundation Graduate Fellowship. REPOSITORY http://scgroup.hpclab.ceid.upatras.gr REF: In Advances in Web Intelligence and Data Mining, M. Last, P.S. Szcepaniak, Z. Volkovich and A. Kandel eds., Springer Studies in Computation...

Technical Report GIT-CERCS-06-03 The Sleepy Keeper Approach: Methodology, Layout and Power Results for a 4-bit Adder