Dirk W van Bekkum 1925–2015

The van der Waerden Number W(2, 6) Is 1132

On the van der Waerden numbers w(2;3,t)

On the van der Waerden numbers w(2; 3, t) Abstract In this paper we present results and conjectures on the van der Waerden numbers w(2; 3, t). We have computed the exact value of the previously unknown van der Waerden number w(2; 3, 19) = 349, and we provide new lower bounds for t = 30, we conjecture these bounds to be exact. The lower bounds for w(2; 3, t) with t = 24,. .. , 30 refute the conj...

Dirk Bergemann † Alessandro Bonatti

A monopolist sells informative experiments to heterogeneous buyers who face a decision problem. Buyers differ in their prior information, and hence in their willingness to pay for additional signals. The monopolist can profitably offer a menu of experiments. Even under costless acquisition and degrading of information, the optimal menu is quite coarse. The seller offers at most two experiments,...

Nicole Brass , Dirk Heckel

With the rapid advances in tumor genetics, an increasing number of amplifications have been identified in various human neoplasms (4). Examples of oncogenes amplified in tumors include N-myc and HER-2/neu, which have been proposed as prognostic markers in neuroblastoma and breast cancer, respectively (5,7). To date, most of the information on the amplification of genes has been gathered from co...

Dirk Zeller Æ Shawn Booth

Fisheries catches from Pacific Island coral reefs are rarely recorded in official statistics. Reconstruction of catch estimates with limited hard data requires interpolation and assumptions, justifiable only by the unsatisfactory alternative of continued substitution of zero catches, a common policy interpretation for ‘no data’. Uncertainties associated with reconstructions are high, requiring ...