Matchings from a set below to a set above

AbstractOne way to represent a matching in a graph of a set A with a set B is with a one-to-one function m : A → B for which each pair {a, m(a)} is an edge of the graph. If the underlying set of vertices of the graph is linearly ordered and every element of A is less than every element of B, then such a matching is a down-up matching. In this paper we investigate graphs on well-ordered sets of type α and in many circumtances find either large independent sets of type β or down-up matchings with the initial set of some prescribed size γ. In this case we write α → (β, γ-matching)

Geology of the Millers River Delta

Guidebook for field trips in southwestern New Hampshire, southeastern Vermont, and north-central Massachusetts: New England Intercollegiate Geological Conference, 80th annual meeting, October 14, 15 and 16, 1988, Keene, New Hampshire: Trip B-

Maximal Tukey types, P-ideals and the weak Rudin-Keisler order

In this paper, we study some new examples of ideals on $\omega$ with maximal Tukey type (that is, maximal among partial orders of size continuum). This discussion segues into an examination of a refinement of the Tukey order -- known as the "weak Rudin-Keisler order" -- and its structure when restricted to these ideals of maximal Tukey type. Mirroring a result of Fremlin on the Tukey order, we also show that there is an analytic P-ideal above all other analytic P-ideals in the weak Rudin-Keisler.Comment: 17 page

AN ECONOMIC ANALYSIS OF GENETIC INFORMATION: LEPTIN GENOTYPING IN FED CATTLE

The use of genetic knowledge is widespread in crop production but is just recently being utilized in livestock production. This study investigates the economic value to feedlots of a polymorphism in the bovine leptin gene. Previous studies indicate that this polymorphism is associated with fat deposition. Since fed cattle are often priced on a grid that considers both yield and quality grades, fat deposition is an important factor in the value and profitability of fed cattle. Using data from 590 crossbred steers and heifers, we estimate growth curves for relevant biological traits, both with and without genotypic information. Using the resulting functions, we then simulate carcass traits to various days-on-feed and compute the associated profit under three price grids. Maximum profits are determined in an unconstrained profit maximization model and in a model that constrains cattle to be marketed in 45-head "potloads." Results indicate that leptin genotypic knowledge has little impact on optimal days-on-feed but may play a role in valuing feeder cattle. The differences in value of cattle varied by as much as $37 per head between genotypes.genetics, leptin genotype, beef cattle, value of information, Livestock Production/Industries,