Nonmanipulable voting schemes when participants' interests are partially decomposable

Recent papers by Barberá and Peleg and by Zhou have established that the Gibbard-Satterthwaite Theorem remains valid when individuals are restricted to reporting only reasonable preferences. We present a theorem that covers situations in which, as in Barberá-and-Peleg and Zhou, preferences may be restricted to reasonable ones, but in which, additionally, it may be known in advance that some dimensions of the social decision do not affect all the participants — i.e., in which the social decisions are partially decomposable into decisions that affect only subsets of the participants. As in the previous theorems, the conclusion of this new theorem is that nonmanipulable voting schemes must be dictatorial.An early version of this paper was delevered at the 1989 NBER-NSF Conference on Decentralization at Cal Tech; comments by the conference participants are appreciated, as are comments by James Schmitz.     

Matrix completion with nonconvex regularization: spectral operators and scalable algorithms

Statistics and Computing - In this paper, we study the popularly dubbed matrix completion problem, where the task is to “fill in” the unobserved entries of a matrix from a small subset...     

Assessing international organizations’ support to social enterprise

This article takes stock of a sample of interventions and programmes across different countries and regions supported by international organizations to foster the development of social enterprise. The primary objective of the article is to generate a compilation of such interventions and draw some lessons about their potential contribution to the growth and sustainability of the sector. The results indicate that international organizations’ support to social enterprise has focused primarily on the provision of financial resources, notably loans and grants. While programmes remain largely unassessed, the few available rigorous evaluations show that social enterprise has the potential to be a cost‐effective mechanism to deliver basic social services to the poor. The article proposes a set of policy recommendations directed primarily to international organizations and the public administration to improve and enhance their support to the sector.     

A new class of slash-elliptical distributions

In this paper, we consider a generalization of the modified slash distribution. We define the new family through the quotient between an elliptically distributed random variable and the power of an exponential random variable with parameter equals to 2, both independent. We use the same idea to extend the model for the multivariate case and study general important properties from the resultant family. We perform inference by the method of moments and maximum likelihood. We present a simulation study which indicates satisfactory parameter recovery by using the estimation approaches. Illustrations reveals that it has potential for doing well in real problems.     

A note on the EM algorithm for estimation in the destructive negative binomial cure rate model

In this note we present a modification in the EM algorithm for the destructive negative binomial cure rate model. This alteration enables us to obtain the estimates of the whole parameter vector from the complete log-likelihood function, avoiding the corresponding observed log-likelihood function, which is more involved. To achieve this goal, we resort to the mixture representation of the negative binomial distribution in terms of the Poisson and gamma distributions.     

Interest rate setting at the ECB: Individual preferences and collective decision making

We investigate whether the members of the Governing Council of the European Central Bank take into account the specific economic conditions of their states of origin, to set the interest rates for the euro area. Testing the national-based view against the Europeanist perspective is a challenging issue, because voting inside the Governing Council is secret, and the final outcome depends both on the individual preferences and the procedures followed by the Governing Council to arrive at a decision. Accordingly, we model interest rate setting as a two-stage process: first, each member of the Governing Council sets his/her preferred rate, and next the Governing Council meets and decides the actual figure. Our empirical analysis shows that domestic developments play a major role in determining the preferred interest rate of the each member; and that some members exert agenda setting power, that precludes some interest rate policies to be considered at the meeting.     

Modelling of socio-ecological connectivity. The rural-urban network in the surroundings of Madrid (Central Spain)

As most of Europe’s metropolitan landscapes grow, a change is occurring in their surrounding rural environment. The consequences thereof mainly involve losses of traditional land uses and changes in the socioecomic structures of the local population. The lack of coupling ‘urban society-countryside’ can be considered to constitute a driving force of this process. The present paper focuses upon the rural-urban network around the metropolis of Madrid (Central Spain). We developed a quantitative model to explain the socio-ecological rural-urban linkages, taking into account the influence of the metropolis in the network of neighbouring municipalities. The results show a rural landscape gradient ranging from silvo-pastoral to agricultural land uses and maintaining different interactions with the local socioeconomy. Urban-rural polarisation of the territory and accessibility to the metropolis are the main factors influencing the landscape dynamics. Territorial cohesion among municipalities and connectivity with the metropolis are factors determining the socio-ecological structure. The agricultural area presents good social cohesion, but a weak connection with the City. The silvo-pastoral landscape, on the contrary, maintains prominent links with the metropolis, but a non-significant interconnection between the small towns. The model tested constitutes a useful tool for analysing socio-ecological connectivity and for quantifying, designing and promoting territorial cohesion policies.     

Ethnic Origins and Religious Transformations in the Afro-Colombian Muslim Community of Buenaventura

The aim of this article is to analyse the origins and transformations of a Muslim community in western Colombia. The history of this small religious group of Afro-Colombians is presented over a period divided into four phases. This division is based on four dominant interpretations of Islamic doctrines adopted by the majority of the group over a period of time. These changes were not only due to religious motivations but also due to changes in the social milieu and the need for taking advantage of emerging opportunities. The religious conversion of Afro-Colombians to Islam took place within the complex socio-political context of the Colombian conflict which began in mid-1960s and is still ongoing. The adoption of this new religious perspective did not evolve in an isolated manner, rather, it transformed the identity of the community by strengthening the value of ethnic differences in a place of segregation. In this context, this paper analyses the role of religion as an important element in the construction of ethnic identity. It is also important to recognize that this cultural negotiation happens at the margins of the dominant society, which views Afro-Colombian minorities negatively or simply ignores their presence.     

Cognitive ergonomics: the use of mind mapping tool in maintaining productive sector of a Brazilian paper company

The use of mind maps as a method of building knowledge, planning, organizing activities and ideas can be seen in the literature related to ergonomics. The results of such use are relevant and its use in academic area found. However, regarding to its use in industrial environments, studies can't not be found. With this scenario, and based on the perception of the ergonomist about the importance of using methods such as mind maps in support of human cognition, it seems pertinent to its use in industry sectors whose cognitive demand requires. Given these assumptions, this study aimed to apply the method of Mind Maps in Productive Maintenance sector of a Brazilian paper. The Productive Maintenance sector in the Paper Industry has an important contribution to operational performance. With practical Predictive Maintenance, Preventive Maintenance and Corrective Maintenance, the industry advocates to make the machines to produce paper is not to stop producing when they are programmed to do so. Among the practices cited, the Preventive Maintenance is one that leads to pre-determined intervals in order to reduce the possibility of placing the equipment in a condition below the required level of acceptance. Therefore, this article aims to propose using the tool "mental maps" in order to collaborate in planning and implementation of preventive maintenance activities in the sector of mechanical maintenance of a pulp and paper industry in southern Brazil. The study investigated the maintenance sector through its employees, who went through training about the tool and then use it and ergonomists company.     

A new cure rate model based on the Yule–Simon distribution with application to a melanoma data set

In this paper, a new survival cure rate model is introduced considering the Yule–Simon distribution [12 H.A. Simon, On a class of skew distribution functions, Biometrika 42 (1955), pp. 425–440.[Crossref], [Web of Science ®] , [Google Scholar]] to model the number of concurrent causes. We study some properties of this distribution and the model arising when the distribution of the competing causes is the Weibull model. We call this distribution the Weibull–Yule–Simon distribution. Maximum likelihood estimation is conducted for model parameters. A small scale simulation study is conducted indicating satisfactory parameter recovery by the estimation approach. Results are applied to a real data set (melanoma) illustrating the fact that the model proposed can outperform traditional alternative models in terms of model fitting.