Consonance, Symmetry and Extended Outputs

In many real-world situations, performers always adopt different energy levels (strategies) to participate. Different from pre-existing results, this paper is devoted to proposing several generalized power outputs of the marginal index, the Banzhaf–Coleman index, and the Banzhaf–Owen index, respectively, by assigning different energy levels to all performers. Since these extended power outputs may not be efficacious, we further define the efficacious extensions of these power outputs, respectively. For each of these efficacious power outputs, we demonstrate that there exists a corresponding reduced game and related consonance property that can be used to characterize it. By focusing on the properties of symmetry and accordance, several axiomatic results are also introduced.

Firearms Effects on Tsimane’ Hunting and Traditional Knowledge in Bolivian Amazonia

Subsistence hunting is a key activity for indigenous Amazonian people. Traditional Tsimane’ bow hunting was strongly affected by the introduction of firearms over 30 years ago. Tsimane’ of Bolivia maintain traditional hunting techniques with bows and arrows, sometimes in conjunction with modern firearms. This study explores Tsimane' perceived costs and benefits of bow- versus gun-hunting. We consider cultural conservation in addition to factors typical in ecological comparisons of traditional and introduced hunting technologies. Firearms are expensive and less reliable than bows and arrows. Costs of purchasing firearms requires market engagement and surplus production to generate cash. Tsimane’ do not identify overhunting as one of the costs of firearms; though multiple studies show reduced game populations in areas under moderate to intense gun-hunting pressure. In sum, Tsimane’ identify multiple benefits to traditional hunting technology, while firearms have a strong effect of the loss of knowledge regarding fabrication of bows and arrows, and present a challenge to Tsimane’ cultural identity as bow-hunters.

Power allocation rules under multicriteria situation

Under multicriteria situations, we define a power mensuration rule and its efficient extension by applying maximal-utilities among level (decision) vectors. We also adopt some axiomatic results to present the rationalities for these two rules. Based on the notions of reduced game and excess function respectively, we introduce different formulation and dynamic results for the efficient extension.

Subordinated Hedonic Games

Hedonic games are simple models of coalition formation whose main solution concept is that of core partition. Several conditions guaranteeing the existence of core partitions have been proposed so far. In this paper, we explore hedonic games where a reduced family of coalitions determines the development of the game. We allow each coalition to select a subset of it so as to act as its set of representatives (a distribution). Then, we introduce the notion of subordination of a hedonic game to a given distribution. Subordination roughly states that any player chosen as a representative for a coalition has to be comfortable with this decision. With subordination we have a tool, within hedonic games, to compare how a “convenient” agreement reached by the sets of representatives of different groups of a society is “valued” by the rest of the society. In our approach, a “convenient” agreement is a core partition, so this paper is devoted to relate the core of a hedonic game with the core of a hedonic game played by the sets of representatives. Thus we have to tackle the existence problem of core partitions in a reduced game where the only coalitions that matter are those prescribed by the distribution as a set of representatives. We also study how a distribution determines the whole set of core partitions of a hedonic game. As an interesting example, we introduce the notion of hedonic partitioning game, which resembles partitioning games studied in the case where a utility, transferable or not, is present. The existence result obtained in this new class of games is later used to provide a nonconstructive proof of the existence of a stable matching in the marriage model.

ESTUDO COMPARATIVO DAS ACÇÕES OFENSIVAS DESENVOLVIDAS EM SITUAÇÃO DE JOGO FORMAL E DE JOGO REDUZIDO NUMA EQUIPA DE BASQUETEBOL DE INICIADOS

O presente trabalho tem como objectivo situar, no contexto do processo de transformações das concepções e abordagens metodológicas do ensino e formação nos jogos desportivos colectivos (JDC), o papel assumido pelo Jogo Reduzido (JR), no processo de aprendizagem do jogo de basquetebol. Descrevemos e comparamos a freqüência e a qualidade das intervenções dos jogadores em situação de finalização/ a partir de acções tácticas individuais e de grupo nas situações de: (1) Jogo Formal (JF) (5x5); e (2) Jogo Reduzido (JR) (3x3 em meio-campo). A amostra foi constituída por uma equipa do escalão infantil feminino (n= 1 2), com a média de 1 1,5 anos de idade, que se iniciavam na modalidade pela primeira vez e realizavam 2 treinos por semana. De acordo com os resultados obtidos, podemos concluir que o Jogo Reduzido (3x3) possibilita uma maior participação do jogador, uma menor probabilidade para a ocorrência de atitudes passivas, uma elevada freqüência de contactos com a bola e um maior sucesso na finalização das acções ofensivas. Assim, podemos considerar que no processo de ensino do basquetebol é defensável a constituição de unidades temáticas do ensino do jogo que tenham por referência o jogo reduzido. Acknowledging the conceptual and methodological changes in the teaching of team sports, the aim of the present study was to examine the impact of the partial game form over the opportunities to actively participate in the game play. We described and compared the frequency and quality of the strategical responses performed by players within offensive game play situations. We have considered both individual and group offensive actíons in both game forms: 5x5 full court game form and 3x3 half court game form. The sample was composed by a young female basket team (n= 1 2) with an average of 1 1 .5 years old. Ali players were in theír first season, and they practised twice a week. The results showed that the 3x3 half court game form provided the players with more chances to participate, fewer chances for passive attitude, a greater frequency of bali contact and an increased success ín scoring after offensive actíons. Evidence seems to support the suitability of taking reduced game form as a reference to design basketball programs in school settings

TWISTED DUAL GAMES AND THEIR PROPERTIES

We define a duality of solutions in coalitional games that we call a twisted duality. This twisted duality extends the rule of self-duality in bankruptcy problems. After showing that the prekernel and prenucleolus exhibit twisted duality, we define a twisted reduced game property and characterize the prekernel and prenucleolus by axioms including this property. We note that the Shapley value satisfies twisted duality, and we define another twisted reduced game property by and characterize the Shapley value by axioms including this property.