Network externalities and long-run market shares

We study a dynamic duopoly model with network externalities. The value of the product depends on the current and past network size. We compare the market outcome to a planner. With equal quality products, the market outcome may result in too little standardization (i.e. too many products active in the long run) but never too much. The potential inefficiency is non-monotonic in the strength of the network effect, being most likely for intermediate levels. When products differ in quality, an inferior product may dominate even when the planner would choose otherwise, but only if the discount factor is sufficiently large     

Walras and pareto on the meaning of the solution concept in general equilibrium theory

The notion of solution plays a crucial role in the conceptual system of Léon Walras, the founder of the General Equilibrium Theory (GET). In this paper, after introducing the two solution concepts employed by Walras in the development of his version of GET, respectively called the “theoretical” and the “practical” solution, we discuss the problems such peculiar conception gives rise to, as well as the attempts Walras makes to dodge them. Then we explain why and to what extent Pareto, Walras’ immediate successor and co-founder of GET, departs from Walras’ original conception, progressively developing an independent viewpoint on the issue of equilibrium computability in GET. (JEL:B13, B21, B31, B41, C62, C68, D50)     

IR journal and conference literature from the 1960s to the 1990s: What can HR learn from it? Where is it headed?

The industrial relations (IR) literature has changed notably from the early 1960s until the late 1990s. Yet it has retained an externalist flavor — a sense that the key variables determining outcomes are often outside the control of firm-level actors. However, the kind of externalism found in the modern IR literature differs notably from that of the past. Externalism today is seen as labor market and personal variables — often in an econometric formulation — rather than grand social forces. Generally, the IR literature has moved toward sophisticated empiricism and toward a labor economics paradigm. To the extent that the older grand themes remain, they are more likely to be found in IR books rather than in academic journals. Human resource (HR) academics and practitioners can nonetheless benefit from the IR approach, even though the tyranny of tenure review has made journal articles in IR less readable. The IR literature emphasizes that labor–market forces, sometimes stemming from product and financial markets, matter to HR outcomes. And it regards conflict more as a source of information rather than just a cause of lost productivity.     

An alternative procedure for imputing missing data based on principal components analysis

This work entailed tackling the significant problem of missing data which was solved by identifying a new substitution procedure, following an empirical approach based on the analysis of the information contained in the entire set of data collected. This procedures offers a number of advantages compared to other techniques commonly mentioned in the statistical–methodological literature.     

Hamburg's Spaces of Danger: Race,Violence and Memory in a Contemporary Global City

Germany today is experiencing the strongest upsurge of right‐wing populism since the second world war, most notably with the rise of Pegida and Alternative für Deutschland. Yet wealthy global cities like Hamburg continue to present themselves as the gatekeepers of liberal progress and cosmopolitan openness. This article argues that Hamburg's urban boosterism relies on, while simultaneously obscuring, the same structures of racial violence that embolden reactionary movements. Drawing on the work of Walter Benjamin and Allan Pred, we present an archaeology of Hamburg's landscape, uncovering some of its ‘spaces of danger’—sites layered with histories of violence, many of which lie buried and forgotten. We find that these spaces, when they become visible, threaten to undermine Hamburg's cosmopolitan narrative. They must, as a result, be continually erased or downplayed in order to secure the city as an attractive site for capital investment. To illustrate this argument, we give three historical examples: Hamburg's role in the Hanseatic League during the medieval and early modern period; the city under the Nazi regime; and the recent treatment of Black African refugees. The article's main contribution is to better situate issues of historical landscape, collective memory and racialized violence within the political economy of today's global city.     

Testing for time-invariant unobserved heterogeneity in generalized linear models for panel data

Recent literature on panel data emphasizes the importance of accounting for time-varying unobservable individual effects, which may stem from either omitted individual characteristics or macro-level shocks that affect each individual unit differently. In this paper, we propose a simple specification test of the null hypothesis that the individual effects are time-invariant against the alternative that they are time-varying. Our test is an application of Hausman (1978) testing procedure and can be used for any generalized linear model for panel data that admits a sufficient statistic for the individual effect. This is a wide class of models which includes the Gaussian linear model and a variety of nonlinear models typically employed for discrete or categorical outcomes. The basic idea of the test is to compare two alternative estimators of the model parameters based on two different formulations of the conditional maximum likelihood method. Our approach does not require assumptions on the distribution of unobserved heterogeneity, nor it requires the latter to be independent of the regressors in the model. We investigate the finite sample properties of the test through a set of Monte Carlo experiments. Our results show that the test performs well, with small size distortions and good power properties. We use a health economics example based on data from the Health and Retirement Study to illustrate the proposed test.     

The Volatility of Foreign Portfolio Investment and the Access to Finance of Small Listed Firms

This paper examines the impact of foreign portfolio investment (FPI) volatility on the access to capital of small listed firms. The volatility of FPI is significantly associated with decreased access to finance for small listed firms only in years when nations are considered less “creditworthy.” Even in these times, however, the benefits of FPI are not completely depleted. These results underscore the significance of both a good financial system that minimizes capital flow volatility and national creditworthiness in inspiring confidence in foreign investors.