Certificates of optimality: the third way to biproportional apportionment

The biproportional apportionment problem (BAP) must be faced in many proportional electoral systems where seats must be allocated to parties within regions. BAP is a non-trivial optimization problem, and only sophisticated algorithms are currently available for solving it. The issue is: are they “writable” as an actual law? Citizens rightly demand simple, easy to understand, voting systems. The alternative, though, seems to have simple, but unsound electoral laws. We propose the following way out of this dilemma: leave to a mathematically sophisticated algorithm the task of producing an optimal apportionment, but attach to it a “certificate of optimality”, that is, describe a simple procedure whereby anybody can check, through some elementary operations, that the seat allocation output by the algorithm is indeed an optimal apportionment. We discuss one such certificate, based on the Max flow- min cut Theorem, relative to a parametric max flow method of ours for BAP.     

整个世界都在变成科学元勘 ——法迪勒·马赞德兰尼对话布鲁诺·拉图尔

如何在这片森林中生存?如何使之保持活力?拉图尔就当前的全球生态危机提出了这些问题,但当应用于STS的"森林"——或者用拉图尔自己的隐喻"生物多样性"时,这些问题也同样恰当.在访谈中,拉图尔描绘了一幅STS生存模式的特殊图景.在这一图景中,STS既非对科学的批判也非对科学的辅助,而是通过教育与合作将不言而喻的STS敏感性融入科学之中.尽管拉图尔承认STS领域在立场和进路上存在诸多差异,但他淡化了这些差异,将所有"感染"STS人的定义特征设定为共同致力于将以大写的"S"开头的科学(Science)转化为一些可以进行经验研究的问题.毫无疑问,他所描绘的是一幅建构主义的图景,社会科学家和自然科学家、工程师、艺术家以及政治家们在其中共同"建设世界".     

Comparative Statics,Informativeness, and the Interval Dominance Order

We identify a new way to order functions, called the interval dominance order, that generalizes both the single crossing property and a standard condition used in statistical decision theory. This allows us to provide a unified treatment of the major theorems on monotone comparative statics with and without uncertainty, the comparison of signal informativeness, and a non‐Bayesian theorem on the completeness of increasing decision rules. We illustrate the concept and results with various applications, including an application to optimal stopping time problems where the single crossing property is typically violated.     

Contemplative Methods Meet Social Sciences: Back to Human Experience as It Is

The aim of this paper is to trace a pathway connecting contemplative knowledge and practices with the social sciences. Contemplative knowledge and practices offer material for reflection in social science even concerning their very foundation. I'll found an opportunity for meshing our disciplinary tools with this knowledge as I introduced it in a health promotion program. The result will be a transdisciplinary confluence of different lines of inquiry contributing to a new perspective of self and social action. First of all I will give a definition of contemplative knowledge and practices. Then, I will make a bridge between the contemplative approach and the social sciences, showing the contribution that symbolic interactionism can play. I will illustrate the perspective drawing on an action research program called Auriga aimed at smoking cessation and reduction among health professionals. The aim of this paper is focused on the specification of the conceptual background in which such kind of program has been developed. Finally, I outline some implications it could represent for what might be called transformative sociology. I believe that contemplative knowledge could contribute to disentangle some of the unanswered questions and concerns in the social sciences, once they dismiss for a while their scientistic perspective. The secular redefinition of tools mainly belonging to the wisdom traditions represents an innovation that can reshape what we intend by the self and experience, contributing to what is called the “social transformation from within,” a pragmatic and wise approach to change at any level.     

Influence Measures in Quantile Regression Models

In this article, we use the asymmetric Laplace distribution to define a new method to determine the influence of a certain observation in the fit of quantile regression models. Our measure is based on the likelihood displacement function and we propose two types of measures in order to determine influential observations in a set of conditional quantiles conjointly or in each conditional quantile of interest. We verify the validity of our average measure in a simulated data set as well in an illustrative example with data about air pollution.     

Incentives to cooperate and the discretionary power of courts in divorce law

In this paper, we study how the uncertainty in the behavior of judges provides parents going to separate with incentives to cooperate. We introduce a model of cooperative bargaining to describe the behavior of parents whose preferences satisfy the characterization of risk averse/pessimistic types proposed by Yaari (1987, Econometrica, 55, 95–116) in his Dual Decision Theory under Risk. The behavior of the judge is modeled in a simple manner: he is either supposed to follow a strict rule (we will say that he uses an imperative scale of alimony), or he may use discretion (he uses an indicative scale of alimony). The point is that for both parents the judgment represents an external opportunity to divorce—the disagreement point in negotiation. We show that the effective decision of parents (cooperation versus trial) depends on the specific structure of the costs and risks associated with divorce procedures, such that more uncertainty at trial increases the incentives to cooperate for risk averse parents. Finally, we give a characterization of the optimal degree of the judges’ discretionary power required to maximize the parents’ gains from negotiation.

Learning While Voting: Determinants of Collective Experimentation

This paper combines dynamic social choice and strategic experimentation to study the following question: How does a society, a committee, or, more generally, a group of individuals with potentially heterogeneous preferences, experiment with new opportunities? Each voter recognizes that, during experimentation, other voters also learn about their preferences. As a result, pivotal voters today are biased against experimentation because it reduces their likelihood of remaining pivotal. This phenomenon reduces equilibrium experimentation below the socially efficient level, and may even result in a negative option value of experimentation. However, one can restore efficiency by designing a voting rule that depends deterministically on time. Another main result is that even when payoffs of a reform are independently distributed across the population, good news about any individual's payoff increases other individuals' incentives to experiment with that reform, due to a positive voting externality.     

Insurability and Mitigation of Flood Losses in Private Households in Germany

In Germany, flood insurance is provided by private insurers as a supplement to building or contents insurance. This article presents the results of a survey of insurance companies with regard to eligibility conditions for flood insurance changes after August 2002, when a severe flood caused 1.8 billion euro of insured losses in the Elbe and the Danube catchment areas, and the general role of insurance in flood risk management in Germany. Besides insurance coverage, governmental funding and public donations played an important role in loss compensation after the August 2002 flood. Therefore, this article also analyzes flood loss compensation, risk awareness, and mitigation in insured and uninsured private households. Insured households received loss compensation earlier. They also showed slightly better risk awareness and mitigation strategies. Appropriate incentives should be combined with flood insurance in order to strengthen future private flood loss mitigation. However, there is some evidence that the surveyed insurance companies do little to encourage precautionary measures. To overcome this problem, flood hazards and mitigation strategies should be better communicated to both insurance companies and property owners.     

The experience effect and pricing for agricultural products

It has been found that for a wide range of industrial products the unit prices and costs decrease by a constant percentage when production volume doubles—this is called the experience effect. This unit price behaviour is also observed for certain classes of basic agricultural products. As international market competition increases, price behaviour differences among countries may lead farmers, their organizations and governments to better understand what are the causes of the differences so that they can maintain and improve their competitive position internationally.     

Bayesian deconvolution of oil well test data using Gaussian processes

We use Bayesian methods to infer an unobserved function that is convolved with a known kernel. Our method is based on the assumption that the function of interest is a Gaussian process and, assuming a particular correlation structure, the resulting convolution is also a Gaussian process. This fact is used to obtain inferences regarding the unobserved process, effectively providing a deconvolution method. We apply the methodology to the problem of estimating the parameters of an oil reservoir from well-test pressure data. Here, the unknown process describes the structure of the well. Applications to data from Mexican oil wells show very accurate results.