Search results for "selection"
showing 10 items of 1940 documents
Complexity Selection of the Self-Organizing Map
2002
This paper describes how the complexity of the Self-Organizing Map can be selected using the Minimum Message Length principle. The use of the method in textual data analysis is also demonstrated.
Optimal selection of thek best of a sequence withk stops
1997
We first consider the situation in which the decision-maker is allowed to have five choices with purpose to choose exactly the five absolute best candidates fromN applicants. The optimal stopping rule and the maximum probability of making the right five-choice are given for largeN eN, the maximum asymptotic value of the probability of the best choice being limN→∝P (win) ≈ 0.104305. Then, we study the general problem of selecting thek best of a sequence withk stops, constructing first a rough solution for this problem. Using this suboptimal solution, we find an approximation for the optimal probability valuesPk of the form $$P_k \approx \frac{1}{{(e - 1)k + 1}}$$ for any k eN.
Selection of the Best Subset of Variables in Regression and Time Series Models
2009
The problem of variable selection is one of the most pervasive model selection problems in statistical applications. Often referred to as the problem of subset selection, it arises when one wants to model the relationship between a variable of interest and a subset of potential explanatory variables or predictors, but there is uncertainty about which subset to use. Several papers have dealt with various aspects of the problem but it appears that the typical regression user has not benefited appreciably. One reason for the lack of resolution of the problem is the fact that it is has not been well defined. Indeed, it is apparent that there is not a single problem, but rather several problems …
Gaining Competitive Advantage through Standardization and Differentiation of Services
2015
The goal of the paper is to study the question of whether or not differences between cultural groups influence the decision of a consumer wishing to avail himself of a particular service. Therefore we have developed a semiotic extension of the means-end approach as the theoretical basis for elaborating a solution to this problem. The conjoint analysis specifies the results of the meansend analysis.
Design and optimisation of an innovative two-hub-and-spoke network for the Mediterranean short-sea-shipping market
2020
Abstract Short Sea Shipping (SSS) is generally considered as a privileged transport mode in terms of reducing road congestion and related external costs. In the last two decades, SSS has attracted a lot of attention in the European Union, where it is also regarded as a key factor for economic and social cohesion between countries. In this regard, the present study proposes a new network design that aims at improving and increasing freight traffic between the north-western and the south-eastern shores of the Mediterranean Basin. The proposed model, designed for Ro-Ro (Roll-on Roll-off) freight transport, tries to overcome the limits of the existing multi-port-calling services through an inno…
Automating the Parameter Selection in VRP: An Off-line Parameter Tuning Tool Comparison
2014
Vehicle route optimization is an important application of combinatorial optimization. Therefore, a variety of methods has been proposed to solve different challenging vehicle routing problems. An important step in adopting these methods to solve real-life problems is to find appropriate parameters for the routing algorithms. In this chapter, we show how this task can be automated using parameter tuning by presenting a set of comparative experiments on seven state-of-the-art tuning methods. We analyze the suitability of these methods in configuring routing algorithms, and give the first critical comparison of automated parameter tuners in vehicle routing. Our experimental results show that t…
The DrosDel Collection
2004
Abstract We describe a collection of P-element insertions that have considerable utility for generating custom chromosomal aberrations in Drosophila melanogaster. We have mobilized a pair of engineered P elements, p{RS3} and p{RS5}, to collect 3243 lines unambiguously mapped to the Drosophila genome sequence. The collection contains, on average, an element every 35 kb. We demonstrate the utility of the collection for generating custom chromosomal deletions that have their end points mapped, with base-pair resolution, to the genome sequence. The collection was generated in an isogenic strain, thus affording a uniform background for screens where sensitivity to genetic background is high. The…
INTRA-CULTIVAR DIVERSITY IN SOUTHERN ITALY OLIVE CULTIVARS DEPICTED BY MORPHOLOGICAL TRAITS AND SSR MARKERS
2014
In this study, SSR analysis was performed on a large number of putative clones of the main olive cultivars from two Italian regions, Sicily and Calabria, in order to study the genetic relatedness, and to detect any degree of genetic diversity, which can be used to unambiguously identify possible superior clones. These putative clones have been collected and observed in the last ten years, following an extensive investigation carried out in traditional olive growing areas, thanks to the reports of farmers, millers, technician, growers and nurseries. The set of microsatellite (SSR) markers used allowed the detection of the genetic diversity, resulting from somatic mutation, indicating the pre…
Intra-cultivar Diversity in sicilian and calabrian olive (olea europaea L.) Cultivars Depicted by Morphological Traits and SSR Markers
2012
In this study, SSR analysis was performed on a large number of putative clones of the main olive cultivars from two Italian regions, Sicily and Calabria, in order to study the genetic relatedness, and to detect any degree of genetic diversity, which can be used to unambiguously identify possible superior clones. These putative clones have been collected and observed in the last ten years, following an extensive investigation carried out in traditional olive growing areas, thanks to the reports of farmers, millers, technician, growers and nurseries. The set of microsatellite (SSR) markers used allowed the detection of the genetic diversity, resulting from somatic mutation, indicating the pre…
Il settore dell’olivicoltura da tavola in Italia: Situazione e prospettive
2020
Table olive Industry in Italy The Italian table olive industry is almost completely located in the southern regions: Sicily and Apulia together account for about two thirds of the entire national production. “Nocellara del Belice”, “Nocellara etnea”, “Bella di Cerignola”, “Ascolana” and “Itrana” are the leading cultivars, together with a large number of other local traditional varieties, often utilised for a double purpose (table olives and oil production). Although Italy is nowadays largely dependent (more than 50%) on importations from other countries (mainly Spain, Greece and Morocco) the domestic production has been declining in the last thirty years and currently accounts for about 2-3…