Search results for "Choice"
showing 10 items of 795 documents
Game theory as a marketing tool: uses and limitations
2011
The growth of complexity of the business environment in which firms operate, calls for more effective tools, able to consider the effect of the strategic choices of the actors of the market and to supply information useful for managerial decision process. Game theory seems to be an ideal candidate for this scope. Nevertheless, because of its axiomatic approach, its validity to highlight and define marketing issues has many critics. This paper analyses the main literature about the use of game theory for marketing management decisions and highlights its limits in this field in order to answer to the question: Can game theory be an effective marketing tool?
Good-genes effects in sexual selection
1999
The magnitude of the effect of good genes as a viability benefit accruing to choosy females remains a controversial theoretical and empirical issue. We collected all available data from the literature to estimate the magnitude of good-genes viability effects, while adjusting for sample size. The average correlation coefficient between male traits and offspring survival in 22 studies was 0.122, which differed highly significantly from zero. This implies that male characters chosen by females reveal on average 1.5% of the variance in viability. The studies demonstrated considerable heterogeneity in effect size; some of this heterogeneity could be accounted for by differences among taxa (birds…
Viability costs of condition-dependent sexual male display in a drumming wolf spider
1996
According to the conditional handicap models females use male ornaments as honest signals of male viability. The assumptions for honest signalling are that the traits are costly and that they reflect male phenotypic condition, and hence optimal trait size is largest in the most viable males. However, experimental evidence for the costs of signalling are scarce. In this study we experimentally tested whether acoustic signalling, drumming, in a wolf spider Hygrolycosa rubrofasciata is a condition dependent, costly trait, and thus offers an honest signal of quality to females. Males of this species court females by drumming dry leaves with their abdomen. Females prefer to mate with males of hi…
Mate choice for offspring performance: major benefits or minor costs?
1998
There is considerable disagreement over whether or not gaining viability benefits to offspring could be substantial enough to overcome the costs of female choosiness. A recent review suggested that the 'lek paradox' might be resolved by large indirect benefits as indicated by highly heritable ornamental traits. We selected males of a wolf spider Hygrolycosa rubrofasciata in relation to their sexual signalling rate (audible drumming). The estimated correlated response in offspring viability was rather small (0.12 s.d.). However, it may be large enough if the costs of being choosy are small. In fact, females mate with better-than-average males just by responding passively to a random drumming…
¿Cómo deciden les jóvenes la transición a la educación postobligatoria? Diferencias entre centros públicos y privados-concertados
2017
Background of INCASI Project H2020-MSCA-RISE-2015 GA 691004. WP1: Compilation El objetivo del presente artículo es examinar el papel que juega la titularidad del centro en el que se cursa la educación secundaria obligatoria (ESO) en la decisión de transitar a la educación postobligatoria. En dicha encrucijada se contemplan también otras variables que se han constatado de gran peso en la toma de decisión como son las notas previas obtenidas, el nivel formativo familiar, el sexo, las expectativas y las aspiraciones, partiendo del modelo decisional de transiciones educativas[1] que contempla el modelo de Boudon sobre los efectos primarios y secundarios. Los resultados obtenidos son los derivad…
Finiteness in a Minimalist Foundation
2008
We analyze the concepts of finite set and finite subset from the perspective of a minimalist foundational theory which has recently been introduced by Maria Emilia Maietti and the second author. The main feature of that theory and, as a consequence, of our approach is compatibility with other foundational theories such as Zermelo-Fraenkel set theory, Martin-Lof's intuitionistic Type Theory, topos theory, Aczel's CZF, Coquand's Calculus of Constructions. This compatibility forces our arguments to be constructive in a strong sense: no use is made of powerful principles such as the axiom of choice, the power-set axiom, the law of the excluded middle.
On female choice, heterozygosity and the lek paradox
2008
The good-genes and compatible-genes benefits of mate choice.
2009
Genetic benefits from mate choice could be attained by choosing mates with high heritable quality ("good genes") and that are genetically compatible ("compatible genes"). We clarify the conceptual and empirical framework for estimating genetic benefits of mate choice, stressing that benefits must be measured from offspring fitness because there are no unequivocal surrogates for genetic quality of individuals or for compatibility of parents. We detail the relationship between genetic benefits and additive and nonadditive genetic variance in fitness, showing that the benefits have been overestimated in previous verbal treatments. We point out that additive benefits readily arise from nonaddit…
Multiple quantitative trait loci influence intra-specific variation in genital morphology between phylogenetically distinct lines of Drosophila monta…
2011
The evolution of animal genitalia has gained renewed interest because of their potential roles during sexual selection and early stages of species formation. Although central to understanding the evolutionary process, knowledge of the genetic basis of natural variation in genital morphology is limited to a very few species. Using an outbred cross between phylogenetically distinct lines of Drosophila montana, we characterized quantitative trait loci (QTLs) affecting the size and shape of the distiphallus, a prominent part of the male intromittent organ. Our microsatellite-based linkage analysis shows that intra-specific variation in the distiphallus involves several QTLs of largely additive …
Sexual selection for genetic quality: disentangling the roles of male and female behaviour
2009
According to the good genes model of sexual selection, females choose males of good heritable genetic quality to obtain offspring with high fitness. However, better mating success of high-quality males can also be brought about by direct interference competition between males, or simply through elevated activity of high-quality males. We examined the roles of different processes leading to sexual selection for genetic quality in Drosophila montana. We manipulated genetic quality of male flies by inducing mutations with ionizing radiation. We then recorded the effects of inherited heterozygous mutations on several aspects of mating behaviour of males and females in two experiments. We found …