MAXIMUM-LIKELIHOOD ESTIMATES OF RACEHORSE EARNINGS AND PROFITABILITY

Thoroughbred racehorses are commonly characterized as unprofitable investments. Previous studies, grouping all racehorses together, estimate that over 80% of all racehorses in training fail to earn enough to recover the variable costs of training. However, these studies are not truly representative, because they fail to account for a number of factors affecting profitability. This study estimates expected purse earnings and profitability of claiming horses in Kentucky. Maximum-likelihood estimates of probability distribution parameters show that expected purse earnings follow an exponential distribution with a mean of $25,267. Profitability is best described by a Gamma distribution with a mean of$4,824. Of the 305 claims analyzed for profitability, 61% were profitable. The results indicate substantial financial risk associated with claiming race horses, but conclude that there are positive economic returns on average.claiming horses, financial risk, maximum likelihood, probability, profitability, thoroughbred, Agribusiness,

Diversity Graphs

Bipartite graphs have long been used to study and model matching problems, and in this paper we introduce the bipartite graphs that explain a recent matching problem in computational biology. The problem is to match haplotypes to genotypes in a way that minimizes the number of haplotypes, a problem called the Pure Parsimony problem. The goal of this work is not to address the computational or biological issues but rather to explore the mathematical structure through a study of the underlying graph theory

In planta expression of A. cellulolyticus Cel5A endocellulase reduces cell wall recalcitrance in tobacco and maize

The glycoside hydrolase family 5 endocellulase, E1 (Cel5A), from Acidothermus cellulolyticus was transformed into both Nicotiana tabacum and Zea mays with expression targeted to the cell wall under a constitutive promoter. Here we explore the possibility that in planta expression of endocellulases will allow these enzymes to access their substrates during cell wall construction, rendering cellulose more amenable to pretreatment and enzyme digestion. Tobacco and maize plants were healthy and developed normally compared with the wild type (WT). After thermochemical pretreatment and enzyme digestion, transformed plants were clearly more digestible than WT, requiring lower pretreatment severity to achieve comparable conversion levels. Furthermore, the decreased recalcitrance was not due to post-pretreatment residual E1 activity and could not be reproduced by the addition of exogenous E1 to the biomass prior to pretreatment, indicating that the expression of E1 during cell wall construction altered the inherent recalcitrance of the cell wall

Precipitation of Trichoderma reesei commercial cellulase preparations under standard enzymatic hydrolysis conditions for lignocelluloses

Comparative studies between commercial Trichoderma reesei cellulase preparations show that, depending on the preparation and loading, total protein precipitation can be as high as 30 % under standard hydrolysis conditions used for lignocellulosic materials. ATR-IR and SDS-PAGE data verify precipitates are protein-based and contain key cell wall hydrolyzing enzymes. Precipitation increased considerably with incubation temperature; roughly 50–150 % increase from 40 to 50 °C and 800 % greater at 60 °C. All of the reported protein losses translated into significant, and often drastic, losses in activity on related 4-nitrophenyl substrates. In addition, supplementation with the non-ionic surfactant PEG 6,000 decreased precipitation up to 80 % in 24 h precipitation levels. Protein precipitation is potentially substantial during enzymatic hydrolysis of lignocelluloses and should be accounted for during lignocellulose conversion process design, particularly when enzyme recycling is considered.This work was supported by the project "Demonstrating Industrial scale second generation bioethaol production-Kalundborg Cellulosic Ethanol Plant" under the EU FP7 framework program and the project "Development of improved second generation (2G) bioethanol technology to prepare for commercialization under the Danish Energy Technology and Demonstration Programme (EUDP)

Optimality regions and fluctuations for Bernoulli last passage models

We study the sequence alignment problem and its independent version,the discrete Hammersley process with an exploration penalty. We obtain rigorous upper bounds for the number of optimality regions in both models near the soft edge.At zero penalty the independent model becomes an exactly solvable model and we identify cases for which the law of the last passage time converges to a Tracy-Widom law

MAXIMUM-LIKELIHOOD ESTIMATES OF RACEHORSE EARNINGS AND PROFITABILITY

Thoroughbred racehorses are commonly characterized as unprofitable investments. Previous studies, grouping all racehorses together, estimate that over 80% of all racehorses in training fail to earn enough to recover the variable costs of training. However, these studies are not truly representative, because they fail to account for a number of factors affecting profitability. This study estimates expected purse earnings and profitability of claiming horses in Kentucky. Maximum-likelihood estimates of probability distribution parameters show that expected purse earnings follow an exponential distribution with a mean of $25,267. Profitability is best described by a Gamma distribution with a mean of$4,824. Of the 305 claims analyzed for profitability, 61% were profitable. The results indicate substantial financial risk associated with claiming race horses, but conclude that there are positive economic returns on average

Positively hyperbolic varieties, tropicalization, and positroids

A variety of codimension c in complex affine space is positively hyperbolic if the imaginary part of any point in it does not lie in any positive linear subspace of dimension c. Positively hyperbolic hypersurfaces are defined by stable polynomials. We characterize these varieties using sign variations, and show that they are equivalently defined by being hyperbolic with respect to the positive part of the Grassmannian, in the sense of Shamovich and Vinnikov. Positively hyperbolic projective varieties have tropicalizations that are locally subfans of the type A hyperplane arrangement defined by x =x , in which the maximal cones satisfy a non-crossing condition. This gives new proofs of results of Choe–Oxley–Sokal–Wagner and Brändén on Newton polytopes and tropicalizations of stable polynomials. We settle the question of which tropical varieties can be obtained as tropicalizations of positively hyperbolic varieties in the case of tropical toric varieties, constant-coefficient tropical curves, and Bergman fans. Along the way, we give a new characterization of positroids in terms of a non-crossing condition on their Bergman fans. i