Asymptotic distributions in random graphs with applications to social networks

Various kinds of subgraph counts have been proposed as important statistics in the social sciences: for instance, in connection with studies of the structural properties of social networks. Since the empirical structure in question often involves an element of randomness, subgraph counts are random variables and, consequently, we need to describe their probabilistic properties. In this paper we give a survey of results dealing with the asymptotic distributions of general subgraph counts for a number of standard graph distributions. Although we do not include proofs for all the results, we illustrate the methodology used through studies of asymptotic behaviour for certain subgraph counts.     

International pharmaceutical supply prices: Definitions — problems — policy implications

In cases where the buyer and the seller of goods and services are companies belonging to the same group the prices charged for goods and services are called ‘international delivery prices’ or ‘international transfer prices’. The peculiarities of research-based companies are such that attempts to ascertain in practice what constitutes an ‘appropriate’ international delivery price are beset by a number of problems. Any scheme that is devised to solve the problems of international transfer prices should feature general ‘rules’ on how the various countries ought to share in central costs. As international transfer prices are a prerequisite for an efficient world economy based on the division of labour an agreement should be reached on the design and content of suitable delivery price systems for a research-intensive industry.     

A college athletics recruiting game to teach the economics of rent-seeking

The authors of this article describe an adaptation of the rent-seeking game by Goeree and Holt (1999) to the recruiting of athletes by NCAA Division I football and basketball teams. Students engage in an effort-based lottery, i.e., recruiting to sign a blue-chip prospect. The winner gets the prize—the player's marginal revenue product in excess of his grant in aid. Students recruit in three scenarios: by recruiting legally, by recruiting legally or with illegal bribes, and by offering wages to athletes in an auction. The authors demonstrate the game's use in a principles course, but it is easily adaptable to other courses. To aid instructors unfamiliar with sports and NCAA recruiting, they include a comprehensive lesson plan with suggested readings and multimedia.     

Einzelbesprechungen

Ohne ZusammenfassungAus dem Italienischen übersetzt von M. St. Braun, WienAus dem Italienischen übersetzt von E. Allina, WienAus dem Russischen übersetzt von A. GerschenkronÜbersetzt von Paul Brüll, Wien.     

A comparison of citizen and “expert” preferences using an attribute-based approach to choice

This paper explores whether expert judgements can be taken as a proxy for citizen preferences for determining investment strategies for public goods. As an illustration, we focus on the provision of Public Rights Of Way (PROW) by Local Government Authorities in England. These provide rights of passage over property to those other than the owners, and little information is available on the welfare effects of changes in the provision and use of PROW. Given limited funds, reliance on expert judgement could be a cost effective alternative for decision-making compared with stated preference surveys of citizens. Two methods are compared. The Analytic Hierarchy Process (AHP) is used to elicit expert judgement to proxy citizen preferences for different attributes of PROW. The Choice Experiment (CE) technique is then used to derive preferences directly through personal interviews with citizens. Overall it was found that judicious use of AHP by experts can, in this instance, be used to represent citizen views. However, this result may not be easily generalisable to other settings.     

A network experiment in continuous time: The influence of link costs

In recent work on non-cooperative network formation star-shaped networks play an important role. In a particular theoretical model of Bala and Goyal (2000) center-sponsored stars are the only strict Nash networks. In testing this theoretical model, Falk and Kosfeld (2003) do not find experimental evidence that players select the center-sponsored star. Based on a slight modification of Bala and Goyal’s model, we design a network formation experiment in which, depending on link costs, periphery-sponsored stars and the empty network are the only strict Nash networks. We observe that almost all groups not only reach a strict Nash network once but also switch the center player in periphery-sponsored stars several times. The main innovation in our experiment is to use a continuous time framework which we believe to be a more realistic setting to study behavior in network formation situations and which makes coordination on stars much easier than simultaneous strategy adaptation in discrete time. Electronic Supplementary Material Supplementary material is available in the online version of this article at http://dx.doi.org/10.1007/s10683-006-9125-1. JEL Classification C72 · C92 · D81     

Fundraising and Optimal Policy Rules

This paper develops a simple spatial model of fundraising, in which charities select a target population to solicit donations. First, we show that in a competitive charity market without any intervention, the number of charities in the market and/or the overall net funds raised by charities may be suboptimal. Next, we analyze whether a social planner can prevent such shortcomings and show that a regulatory mechanism can be designed to achieve socially desirable outcomes. In contrast to the previous literature, our model does not necessarily produce monopoly as the optimal market structure. We show that if fixed costs associated with establishing charities are sufficiently low, then the optimal market structure is not a monopoly. Given the importance of the trade‐off between the volume and variety of charitable services, we argue that this result may be of particular interest to policy makers.     

Demographic links to savings in life cycle models: identification of issues for LDCs

The author considers the potential for a link between the recent pattern of demographic transition and intertemporal and inter-country variations in savings rates. Fertility, infant mortality, life expectancy, and levels of female and child labor force participation are among the various demographic factors which affect national savings rates through their effects upon age structure, age-specific individual savings behavior, and their general equilibrium effects upon interest rates, wage rates, and income distribution. The author establishes a simple discrete time life cycle model of savings, explains the issues related to age structure, and discusses the effect of age-specific savings functions, the general equilibrium effects of demographic factors, the effects of life expectancies and child mortalities, and the nature of social security coverages in less developed countries, as well as issues which are especially important for less developed countries. A new strategy for empirically evaluating demographic policies is proposed. That is, one can estimate the age profile of earnings, saving and fertility rates from household survey data. The life tables can then be used to compute the aggregate savings rate and population size. Any demographic policy which affects the fertility rate, life expectancy, and investment in the quality of children will change the aggregate saving and population growth rates. These two aggregate effects could be compared to evaluate demographic policies. The author stresses, however, that changes in different demographic factors will have different short-run and long-run effects upon the savings rate which will also depend upon whether such changes are transitory or permanent.