The Efficiency of Collective Bargaining in Public Schools

This paper develops a bargaining model of wage and employment determination for the public sectror. The solution to the model generates structural wage and employment equations that are estimated using data from New York State teacher-school district collective bargaining agreements. An advantage of this approach is that the major collective bargaining models (monopoly union, right to manage, efficient contracting, and inefficient contracting) are nested in the structural equations based on flexible functional forms and these models can be empirically tested as restrictions on estimated model parameters. The empirical results suggest that the allocation of resources generated by collective bargaining in New York State public schools is, by and large, not Pareto efficient. Furthermore, it is possible to estimate separate measures of union bargaining power over wages and employment. Empirically, it appears that union bargaining power over wages is around 0.53, while bargaining power over employment is around 0.71. In addition, the paper demonstrates the importance of controlling for the nature of the collective agreement when measuring the level of public services that flow to a community in the presence of a unionized public sector work force. Nous proposons un modèle de négociations collectives sur les salaires et l'emploi dans le secteur public. La solution de ce modèle implique des équations structurelles de détermination des salaires et d'emploi qui sont estimées à partir de données provenant des conventions colléctives des écoles publiques de l'état de New York. Notre approche a l'avantage d'englober tous les modèles majeurs de la littérature sur les négociations collectives (syndicat monopole, droit à gérer, négociations efficaces et négociations inefficaces) et de relier chaque modèle à une restriction d'égalité sur un ou plusieurs paramètres estimés. Nos résultats suggèrent que l'allocation des ressources spécifiée dans les conventions collectives des enseignants de l'état de New York n'est, en générale, pas efficace. De plus, notre approche nous permet d'estimer le pouvoir de négociationsur les salaires et sur l'emploi séparément. Nous trouvons un pouvoir de négociation sur les salaires de 0.53, et sur l'emploi de 0.71. Finalement, nous démontrons l'importance de contrôler le caractère endogène des salaires lors de l'analyse des flux des services publics dans un marché syndicalisé.Collective Bargaining, Efficient Contracting, Public Sector Union, Education, Négociations collectives, contrats efficaces, syndicat du secteur public, éducation

Econometric Methods in Staples

statistical models, cross-sectional estimates, fixed effect estimates, panel data

Heritability of three condition surrogates in the yellow dung fly

Condition capture has been proposed as a general mechanism maintaining additive genetic variation, Va, in sexually selected traits under directional selection. It relies on two main assumptions: condition-dependent trait expression and Va in condition. Although there is evidence for the former, direct evidence that condition is heritable is scarce, although this is a requirement of most models of handicap sexual selection. We used a parent-offspring, full-sib, two-container laboratory breeding design in the yellow dung fly Scathophaga stercoraria to demonstrate the broad- and narrow-sense heritability of three surrogates of condition commonly used in sexual selection studies: lipid and glycogen reserves (i.e., physiological condition), body size, and fluctuating asymmetry. All three measures are nutrition dependent and have been linked to sexual selection in free-living yellow dung flies. While lipid reserves and body size were heritable, asymmetry and glycogen reserves were not. Moreover, the evolvability of physiological condition was higher than that of the other two traits. Of the three surrogates, physiological condition is most akin to the original definition, but all have their limitations. We conclude that condition is a useful heuristic concept in evolutionary ecology, but its practical value may be limited by the fact that it cannot be measured directl

Metabolic Physiology of Euthermic and Torpid Lesser Long-Eared Bats, Nyctophilus geoffroyi (Chiroptera: Vespertilionidae)

Thermal and metabolic physiology of the Australian lesser long-eared bat, Nyctophilias geojfroyi, a small (ca. 8 g) gleaning insectivore, was studied using flow-through respirometry. Basal metabolic rate of N. geojfroyi (1.42 ml O2 g−1 h−1) was 70% of that predicted for an 8-g mammal but fell within the range for vespertilionid bats. N. geoffroyi was thermally labile, like other vespertilionid bats from the temperate zone, with clear patterns of euthermy (body temperature >32°C) and torpor. It was torpid at temperatures ≤25°C, and spontaneously aroused from torpor at ambient temperatures ≥5°C. Torpor provided significant savings of energy and water, with substantially reduced rates of oxygen consumption and evaporative water loss. Minimum wet conductance (0.39 ml O2 g−1 h−1 °C−1) of euthermic bats was 108% of predicted, and euthermic dry conductance was 7.2 J g−1 h−1 °C−1 from 5-25°C. Minimum wet and dry conductances of bats that were torpid at an ambient temperature of 15-20°C (0.06 ml O2 g−1 h−1 °C−1 and 0.60 J g−1 h−1 °C−1) were substantially less than euthermic values, but conductance of some torpid bats increased at lower ambient temperatures and approached values for euthermic bats. Metabolic rates of bats torpid at ambient temperatures >10°C and bats euthermic in the thermoneutral zone indicated a metabolic Q10 of 3.9. That high Q10 suggested that there may have been an intrinsic reduction in metabolic rate during torpor, in addition to down-regulation of thermoregulation (which accounted for most of the reduction in metabolic rate) and the normal Q10 effec

Why aren’t signals of female quality more common?

ArticleHighlights In most species females are less ornamented than males. We suggest a novel reason for this pattern. If females signal their sexual quality, they may suffer increased sexual harassment. Ornaments could therefore be especially costly for females.We thank the Editor and the anonymous referees for helpful comments and the Leverhulme Trust, NERC and the Royal Society for funding

Inbreeding alters intersexual fitness correlations in Drosophila simulans.

PublishedJournal ArticleIntralocus sexual conflict results from sexually antagonistic selection on traits shared by the sexes. This can displace males and females from their respective fitness optima, and negative intersexual correlations (r mf) for fitness are the unequivocal indicator of this evolutionary conflict. It has recently been suggested that intersexual fitness correlations can vary depending on the segregating genetic variation present in a population, and one way to alter genetic variation and test this idea is via inbreeding. Here, we test whether intersexual correlations for fitness vary with inbreeding in Drosophila simulans isolines reared under homogenous conditions. We measured male and female fitness at different times following the establishment of isofemale lines and found that the sign of the association between the two measures varied with time after initial inbreeding. Our results are consistent with suggestions that the type of genetic variation segregating within a population can determine the extent of intralocus sexual conflict and also support the idea that sexually antagonistic alleles segregate for longer in populations than alleles with sexually concordant effects.Foundation for Polish Science (FNP)NER

Artificial selection on walking distance suggests a mobility-sperm competitiveness trade-off

Securing matings is a key determinant of fitness, and in many species, males are the sex that engages in mate searching. Searching for mates is often associated with increased mobility. This elevated investment in movement is predicted to trade-off with sperm competitiveness, but few studies have directly tested whether this trade-off occurs. Here, we assessed whether artificial selection on mobility affected sperm competitiveness and mating behavior, and if increased mobility was due to increased leg length in red flour beetles (Tribolium castaneum). We found that, in general, males selected for decreased mobility copulated for longer, stimulated females more during mating, and tended to be better sperm competitors. Surprisingly, they also had longer legs. However, how well males performed in sperm competition depended on females. Males with reduced mobility always copulated for longer than males with high mobility, but this only translated into greater fertilization success in females from control populations and not the selection populations (i.e. treatment females). These results are consistent with a mate-searching/mating-duration trade-off and broadly support a trade-off between mobility and sperm competitiveness

Sexual and natural selection both influence male genital evolution.

Published onlineJournal ArticleResearch Support, Non-U.S. Gov'tRapid and divergent evolution of male genital morphology is a conspicuous and general pattern across internally fertilizing animals. Rapid genital evolution is thought to be the result of sexual selection, and the role of natural selection in genital evolution remains controversial. However, natural and sexual selection are believed to act antagonistically on male genital form. We conducted an experimental evolution study to investigate the combined effects of natural and sexual selection on the genital-arch lobes of male Drosophila simulans. Replicate populations were forced to evolve under lifetime monogamy (relaxed sexual selection) or lifetime polyandry (elevated sexual selection) and two temperature regimes, 25°C (relaxed natural selection) or 27°C (elevated natural selection) in a fully factorial design. We found that natural and sexual selection plus their interaction caused genital evolution. Natural selection caused some aspects of genital form to evolve away from their sexually selected shape, whereas natural and sexual selection operated in the same direction for other shape components. Additionally, sexual and natural selection tended to favour larger genitals. Thus we find that the underlying selection driving genital evolution is complex, does not only involve sexual selection, and that natural selection and sexual selection do not always act antagonistically.NERCLeverhulme TrustRoyal Societ