Conformity based behavior and the dynamics of price competition: a new rational for fashion shifts

This paper deals with dynamic price competition in markets in which the perception of consumers regarding the value of goods depends on the choices of other consumers in the market. In particular, we consider the case in which consumers tend to imitate their peers, generating a conformity effect. In the context of a finite horizon model, we show that conformity based behavior creates new channels of dynamic interaction between firms, changing the nature of price competition. As time evolves, both price strategic complementarity and substitutability may arise along the equilibrium trajectory. This leads to V-shaped equilibrium price paths and oscillating trajectories of market shares. We provide also a new rational for the inversion of fashion trends.dynamic price competition, consumer behavior, conformity, fashion shift

On Gale and Shapley ‘College admissions and stability of marriage’

In this note, we start to claim that established marriages can be heavily destabilized when the population of existing couples is enriched by the arrival of new candidates to marriage. Afterwards, we discuss briefly how stability concepts can be extended to account for entry and exit phenomena affecting the composition of the marriage market.Matching; stability; marriage model; divorce cascades

Study on the efficiency and effectiveness of public spending on tertiary education

The purpose of the study is to assess efficiency in public tertiary education systems across EU countries plus Japan and the US with semi-parametric methods and stochastic frontier analysis.  The study identifies a core group of efficient countries. A good quality secondary system, output-based funding rules, institutions' independent evaluation and staff policy autonomy are positively related to efficiency.  Moreover, the study provides evidence that public spending on tertiary education is more effective in what concerns labour productivity growth and employability when it is coupled with efficiency.Efficiency, effectiveness, public spending, tertiary education, Universities, Study on the efficiency and effectiveness of public spending on tertiary education

Acentuada diferenciação regional numa espécie de caranguejo norte americana ao longo da sua distribuição de origem e em estuários europeus: análise filogeográfica e considerações ecológicas

Rhithropanopeus harrisii (Gould 1841) tem uma distribuição nativa desde o Canadá até ao México e é considerada uma espécie invasora nos rios e estuários da costa noroeste e sudeste do continente americano e na costa Europeia, onde foi descoberto antes de 1874, na Holanda. Neste estudo uma parte do gene citocrómio oxidase subunidade I foi analisada em populações dos EUA e da Europa, de modo a obter a informação sobre a diversidade genética das populações e sobre uma potencial população de origem. Análises morfométricas foram efetuadas através de medições da carapaça. Um gargalo genético deverá ter ocorrido aquando da colonização Europeia e Nova Jersey é a população que mais se assemelha geneticamente à potencial população de origem. A heterogeneidade genética ao longo da costa este dos EUA e da costa Europeia tomou-se evidente. Pela análise morfométrica não foi possível discriminar as populações. Verifica-se que esta espécie ainda se encontra em expansão e que pode usar vários vetores de invasão. /ABSTRACT - Rhithropanopeus harrisii (Gould 1841) has a native distribution from Canada to Mexico and is considered an invasive species in northwestem American, southeastem American and European estuaries and rivers. In Europe it was observed for the first time before 1874, in The Netherlands. In this study we analyzed a part of cytochrome oxidase subunit I gene of populations from the east coast of United States of America and from Europe, in order to assess to a the genetic diversity of the populations and to determine a potential founder population. Morphometric analyses were also performed using measurements of the carapace. A genetic bottleneck might have occurred during the European colonization. New Jersey is the most similar population to the potential founding population and there is evidence of genetic heterogeneity along the North American east coast and European coast. It was not possible to discriminate all populations morphometrically. R. harrisii is still in expansion and might use several invasion mechanisms

On Gale and Shapley 'College admissions and stability of marriage'

In this note, we start to claim that established marriages can be heavily destabilized when the population of existing couples is enriched by the arrival of new candidates to marriage. Afterwards, we discuss briefly how stability concepts can be extended to account for entry and exit phenomena affecting the composition of the marriage market..info:eu-repo/semantics/publishedVersio

Determinants of electoral behavior : a study using individual-level data

Previous research on the impact of reforms to the Portuguese electoral system has assessed mechanical effects assuming that the behavior of individuals would remain the same. We improve on this state of affairs by using a rich dataset to study the impact of district magnitude on three relevant decisions made by individuals: the decision to vote or abstain, the decision to vote sincerely or not and the party choice decision. Then, we use our models to predict the effects of four alternative scenarios: uniform-size circles, a reduction of Members of Parliament to 180, a national circle and single-member circles. Besides making contributions to the understanding of how several individual and contextual-level variables shape the voting behavior of the Portuguese, we make four additional contributions in this study. Firstly, we show that the relationship between district magnitude and the probability of abstention is negative and shows diminishing returns. Secondly, we show that the impact of district magnitude on the probability of voting strategically is strikingly similar to its impact on the probability of abstaining. Thirdly, we show that district magnitude plays an important role in shaping the choice of party by individuals. Finally, by using the models estimated we quantify the impact of different types of redistricting on abstention, sincere voting and party choice

Comparative study of Cr:Nd:YAG and Nd:YAG solar laser performances

To improve the efficiency of Nd3+-doped YAG solar laser, cross-pumped Cr3+ and Nd3+ co-doped YAG ceramic material has attracted more attentions in recent years. The sensitizer Cr3+ ions have broad absorption bands in the visible region. Despite the interests in Cr:Nd:YAG ceramic medium, researchers have achieved significant laser efficiencies with different Nd:YAG single-crystal rods. While it is clear about the effectiveness of Nd:YAG single-crystal rods for solar laser operation, there still exist some concerns about the advantages of Cr:Nd:YAG ceramics in solar-pumped lasers. A 0.9 m diameter Fresnel lens is used as an economical solar collector. A 4 mm diameter, 25 mm length 1.0 at% Nd:YAG single-crystal rod and a 0.1 at% Cr: 1.0 at% Nd:YAG ceramic rod are pumped alternatively within a conical cavity through a secondary concentrator. With the Nd:YAG rod, the maximum laser power is 12.3 W, corresponding to 19.3 W/m2 collection efficiency. With the Cr:Nd:YAG ceramic rod, the maximum laser power is 13.5 W, corresponding to 21.2 W/m2 collection efficiency. This result is, to the best of our knowledge, the highest collection efficiency achieved with Cr:Nd:YAG ceramic medium. There is also a 109% increase in slope efficiency. In summary, we have experimentally observed a moderate, but not significant, advantage of Cr:Nd:YAG ceramics over Nd:YAG single-crystal medium in both solar laser conversion and slope efficiency.authorsversionpublishe

Core-doped Nd:YAG disk solar laser uniformly pumped by six Fresnel lenses

A novel solar laser uniformly pumped by six Fresnel lenses is proposed here. The incident solar radiation is firstly collected and concentrated by six 0.8 m diameter Fresnel lenses and then reflected by other six plane mirrors to a central focal zone, where a laser head is mounted. About 2.5 kW solar power with 3.5 W/mm2 peak solar flux can be achieved in the focal zone. The laser head is composed of a fused silica six-sphere type secondary concentrator that further compresses the concentrated solar power from the six Fresnel lenses-plane mirrors to a core-doped YAG Nd3+:YAG ceramic disk. Optimum pumping parameters and solar laser output powers are found through ZEMAX non-sequential ray-tracing and LASCAD laser cavity analysis, respectively. The laser resonant cavity is formed by a PR 1064 nm output coupler and a HR 1064 nm plane reflector. An 8 mm diameter central hole is drilled through the six-sphere type concentrator to allow the extraction of laser power from the disk. Since only 16 % of the useful solar power is absorbed by the Nd:YAG medium, for 950 W/m2 of terrestrial solar irradiation, the effective solar pump power of 456 W is assumed in ray-tracing analysis. 72.2 W of multimode laser power is predicted for an 8 mm diameter gain medium embedded within a conical undoped YAG cladding, reaching the collection efficiency of 24.1 W/m2. M2 = 16.6 is numerically calculated, corresponding to the brightness figure of merit of 0.26 W. A near uniform absorbed pump profile is achieved.authorsversionpublishe

Brazilian social work

The authors analyse three aspects of Brazilian social work. First, they provide an overview of Brazil, a country marked by extreme inequality that permeates the economic and social relationships of its population, including rapid contradictory economic growth and the preservation of inequality. Second, they examine the main challenges faced by the country’s social workers. Third, they explore whether Brazil’s undergraduate and postgraduate programs are oriented toward professional training that fosters a critical, creative, and propositional perspective.Los autores analizan tres aspectos del trabajo social brasileño: en primer lugar, se ofrece una visión general del Brasil, un país marcado por la desigualdad extrema que impregna las relaciones económicas y sociales de su población, incluyendo un rápido crecimiento económico y el mantenimiento de la desigualdad; en segundo lugar, se examinan los principales retos que afrontan los trabajadores sociales del país; y en tercer lugar, se explora si los programas de pregrado y postgrado de Brasil están orientados hacia la formación profesional que fomente una perspectiva crítica y creativa.Le autrici analizzano tre aspetti del servizio sociale brasiliano. In primo luogo propongono una panoramica sul Brasile, un paese caratterizzato da un'estrema disuguaglianza che permea i rapporti economici e sociali della popolazione, in presenza di una rapida e contraddittoria crescita economica accompagnata dalla conservazione delle disuguaglianze. In seconda battuta esaminano le principali sfide affrontate dagli assistenti sociali nel contesto socio-economico delineato. In terza istanza cercano di capire se i corsi di laurea e post-laurea in Brasile siano orientati ver-so una formazione professionale atta a favorire una prospettiva critica, creativa e propositiva

Shape your career: Opportunities for Early Career Members in 2022 and the experience of applying for an ERS fellowship

In this article, we present the @EuroRespSoc opportunities for ECMs (@EarlyCareerERS) in the upcoming year and describe the experience of applying for an ERS Fellowship, with the key steps and challenges identified.info:eu-repo/semantics/publishedVersio