Distributional aspects of the divisibility of money: an example

Summary. I highlight the importance of the distributional aspects of moneys divisibility by comparing a search-theoretic model with random transfers of indivisible money balances, to one with deterministic transfers of partially divisible balances. Randomization allows price flexibility, as if money were fully divisible. Partial divisibility does not, but allows money redistributions. An example of the relevance of such extensive margin aspects of divisibility is provided.JEL Classification Numbers: D30, D83, E40.I thank Dean Corbae and seminars participants at the Federal Reserve Bank of Richmond, University of Texas at Austin, Purdue University, the Midwest Macroeconomics Meetings, the Central Bank Institute of the Federal Reserve Bank of Cleveland, and the meetings of the Society for the Advancement of Economic Theory, where this work has been presented during the years 2002 and 2003.     

Matching and anonymity

This work introduces a set-theoretic foundation of deterministic bilateral matching processes and studies their properties. In particular, it formalizes a link between matching and informational constraints by developing a notion of anonymity that is based on the agents’ matching histories. It also explains why and how various matching processes generate different degrees of “informational isolation” in the economy. We illustrate the usefulness of our approach to modeling matching frameworks by discussing the classical turnpike model of Townsend.This research is supported in part by the NSF grants EIA-0075506, SES-0128039, DMS-0437210, and ACI-0325846. We thank two anonymous referees for constructive comments that improved the exposition of the paper. We also thank the participants in seminars at the University of Aarhus, Purdue University, University of Texas at Austin, and at the XI Meeting on Real Analysis and Measure Theory in 2004, the spring 2004 Midwest Economic Theory Meeting, the summer 2004 North American and European Econometric Society meetings.     

Analytic derivatives and the computation of GARCH estimates

In the context of univariate GARCH models we show how analytic first and second derivatives of the log-likelihood can be successfully employed for estimation purposes. Maximum likelihood GARCH estimation usually relies on the numerical approximation to the log-likelihood derivatives, on the grounds that an exact analytic differentiation is much too burdensome. We argue that this is not the case and that the computational benefit of using the analytic derivatives (first and second) may be substantial. Furthermore, we make a comparison of various gradient algorithms that are used for the maximization of the GARCH Gaussian likelihood. We suggest the implementation of a globally efficient computation algorithm that is obtained by suitably combining the use of the estimated information matrix with that of the exact Hessian during the maximization process. As this would appear a straightforward extension, we then study the finite sample performance of the exact Hessian and its approximations (that is, the estimated information, outer products and misspecification robust matrices) in inference.     

Quantitative and qualitative insights into consumers’ sustainable purchasing behaviour: a segmentation approach based on motives and heuristic cues

The present study draws on the concepts of motives and heuristics to thoroughly understand consumers’ sustainable consumption behaviour in the context of personal care products. The mixed-methods approach combines real purchasing data with in-depth qualitative data to generate insights with a high external validity. In the first section of the study, quantitative analysis is applied to actual purchasing behaviour (n = 10,772,477) to identify market trends. Three main groupings, along with specific heuristic cues, are established. In the second step, a qualitative study (n = 21) provides deeper insights into consumers’ motives and decision-making processes. By synthesising the quantitative and qualitative research findings, a segmentation approach is developed. Relevant motives and values, and corresponding specific heuristic cues are identified for each consumer segment. Analysis suggests that consumers are motivated by self-interest and environmental motives, and that they use simple heuristic cues to make quick and satisfying purchasing decisions. Both retailers and manufacturers can leverage these insights to seize the opportunities of the developing market for sustainable personal care products.     

Pflegeberatung ist Vertrauenssache

M?ngeln in der h?uslichen Pflege pr?ventiv begegnen – Vertrauen ohne Kontrolle, Routine, überforderung oder das Nichtbeachten des Beziehungsgeflechtes zwischen Pflegenden und Gepflegten führt oft zu Problemen. Der Gesetzgeber verpflichtete deshalb die Pflegekassen und Tr?gerverb?nde von ambulanten Pflegeeinrichtungen zur Erarbeitung von Richtlinien und standardisierten Verfahren für die Pflegefachberatung. Leider gibt es bislang keine verbindliche Umsetzung.     

Modelling Credit Risk for SMEs: Evidence from the U.S. Market

Considering the fundamental role played by small and medium sized enterprises (SMEs) in the economy of many countries and the considerable attention placed on SMEs in the new Basel Capital Accord, we develop a distress prediction model specifically for the SME sector and to analyse its effectiveness compared to a generic corporate model. The behaviour of financial measures for SMEs is analysed and the most significant variables in predicting the entities' credit worthiness are selected in order to construct a default prediction model. Using a logit regression technique on panel data of over 2,000 U.S. firms (with sales less than $65 million) over the period 1994–2002, we develop a one-year default prediction model. This model has an out-of-sample prediction power which is almost 30 per cent higher than a generic corporate model. An associated objective is to observe our model's ability to lower bank capital requirements considering the new Basel Capital Accord's rules for SMEs.     

Trading horizons and the value of money

This paper shows that fiat money can be feasible and essential even if the trading horizon is finite and deterministic. The result hinges on two features of our model. First, individual actions can affect the future availability of productive resources. So, agents may be willing to sell for money, even if on that date they have no reason to accept it. This makes monetary trade feasible in all preceding dates. Second, agents are anonymous and direct their search for partners. So, gift-giving arrangements may be prevented because agents can misrepresent their consumption needs. This makes money essential in exploiting any gains from specialization and trade.     

Exploring the contribution of innovation intermediaries to the new product development (NPD) process: a typology and an empirical study

In the ‘knowledge economy’ upheld by the European Lisbon strategy, knowledge‐intensive services are considered a key driver for innovation and competitiveness. A category of knowledge‐intensive services that has become of utmost importance in the last few decades is new product development (NPD) services, which interconnect distant knowledge domains with the client firms. In addition to NPD service providers, web‐based innovation intermediaries have started to help innovative firms access dispersed bodies of knowledge. Despite the heterogeneity of their characteristics, however, a clear typology of the strategies used by traditional NPD service providers and web‐based intermediaries to interact with their knowledge sources and with their clients is missing. This typology would be very useful for those firms that are willing to collaborate with innovation intermediaries because it could highlight the typologies of NPD problems different intermediaries are apt to address and the managerial challenges that working with them entails. Developing such a classification framework is the main goal of this paper. The typology proposed in this paper suggests that innovation intermediaries should be distinguished based on the following: (1) the way they access their distributed knowledge sources and (2) the way they deliver value to their clients. By combining these two dimensions, four categories of innovation intermediaries are identified, which are named brokers, mediators, collectors and connectors. A multiple case study analysis involving four innovation intermediaries and 12 of their clients is presented in the paper. The analysis provides exploratory insights into (1) the typologies of NPD problems that each class of intermediaries addresses and (2) the managerial challenges that working with each of them entails. These preliminary findings call for further theoretical and empirical research into the complex interaction among innovation intermediaries, their dispersed sources of knowledge and their clients.     

The dynamic of innovation networks: a switching model on technological change

In this paper, we introduce an agent-based model where heterogeneous firms compare and modify their innovation strategies, so generating an evolving network structure. By implementing dynamic behavioral switching via a fitness mechanism based on agents’ performance, companies can endogenously modify their tactics for technological change and switch among three groups: stand-alone innovators, collaborative innovators and imitators. On the one hand, we study the properties of the emerging networks and we show that they reproduce the stylized facts of innovation networks. Moreover, we focus the analysis on the impact of these three innovation categories on the macro economic aggregate, finding that collaborative companies are those having the highest positive impact on the economic system. On the other hand, we use the model to study the effect of different economic innovation policies in increasing macroeconomic performance.