Around and Around: The Expectations Hypothesis

We show how to construct models of the term structure of interest rates in which the expectations hypothesis holds. McCulloch (1993) presents such a model, thereby contradicting an assertion by Cox, Ingersoll, and Ross (1981), but his example is Gaussian and falls outside the class of finite-dimensional Markovian models. We generalize McCulloch's model in three ways: (i) We provide an arbitrage-free characterization of the unbiased expectations hypothesis in terms of forward rates; (ii) we extend this characterization to a whole class of expectations hypotheses; and (iii) we show how to construct finite-dimensional Markovian and non-Gaussian examples.     

Research cycles

This paper studies the dynamics of fundamental research. We develop a simple model where researchers allocate their effort between improving existing fields and inventing new ones. A key assumption is that scientists derive utility from recognition from other scientists. We show that the economy can be either in a regime where new fields are constantly invented, and then converges to a steady state, or in a cyclical regime where periods of innovation alternate with periods of exploitation. Our analysis provides a rigorous foundation to the Kuhnian theory of scientific evolution. We show that scientists' care for reputation has a strong impact on research dynamics and tends to favor innovation. Especially, innovation fads may emerge. We also study welfare and find that the academic reputational reward system can help align scientists' short-term incentives with society's long-term interests.     

INSTITUTIONS AND PERFORMANCE IN EUROPEAN LABOUR MARKETS: TAKING A FRESH LOOK AT EVIDENCE

Abstract This paper presents a selective survey of the recent literature on labour market institutions and offers new empirical EU‐based evidence on the impact of labour market reforms on employment and labour market adjustment. Although the literature traditionally treats labour market institutions as exogenous, attention shifted recently towards understanding the underlying causes of specific institutional arrangements. As a consequence, the literature highlights the great importance of an efficient policy design exploiting these interactions wisely and identifies general principles for achieving an efficient policy design at both macro and micro levels. Although empirical evidence does not show a major change in terms of intensity of labour market reform after the setting of the Economic and Monetary Union and the creation of the euro, the reforms aiming at strengthening the labour market attachment of vulnerable groups tend to have been successful both in raising their employment and increasing labour market adjustment.     

Agricultural productivity, trade, and industrialisation

Traditional development economics states that industrialisationmust be positively correlated with agricultural developmentas in the American and many European cases. However, some recentindustrialisation experiences suggests a negative link whichcan be supported by a simple Ricardian argument Yet this argumentis not consistent with the agricultural ‘leap forward’that often occurred before industrialisation took place. Here,we develop a model in which, for a closed economy, industrialisationfollows rising agricultural productivity. For a small open economy,multiple equilibria are possible and industrialisation tendsto be associated with low agricultural productivity, but istriggered by sudden changes in it.     

On a class of law invariant convex risk measures

We consider the class of law invariant convex risk measures with robust representation r_h,p(X)=sup_fò₀¹ [AV@R_s(X)f(s)-f^p(s)h(s)] ds\rho_{h,p}(X)=\sup_{f}\int_{0}^{1} [AV@R_{s}(X)f(s)-f^{p}(s)h(s)]\,ds, where 1≤p<∞ and h is a positive and strictly decreasing function. The supremum is taken over the set of all Radon–Nikodym derivatives corresponding to the set of all probability measures on (0,1] which are absolutely continuous with respect to Lebesgue measure. We provide necessary and sufficient conditions for the position X such that ρ _h,p (X) is real-valued and the supremum is attained. Using variational methods, an explicit formula for the maximizer is given. We exhibit two examples of such risk measures and compare them to the average value at risk.     

Is Supply's Actual Contribution to Sustainable Development Strategic and Operational?

This paper addresses the issue of how sustainable supply practices are actually used as a leverage for sustainable development (SD). In order to assess the level of sustainable supply management within an organization, the authors have reviewed the literature extensively and then developed a five‐step maturity model around five management dimensions. A qualitative exploratory approach based on two detailed case studies of organizations whose reputation for SD is recognized internationally has been used. This methodology allowed us to show (1) how sustainable supply practices could be used as a leverage for an organization's sustainable development approach and (2) that sustainable supply practices still have quite a distance to go with regards to the maturity model for sustainable supply, even in organizations that are often mentioned as leaders in the SD area. In these organizations, managers still emphasize environmental considerations, while neglecting practices that would make it possible to reach the three SD objectives simultaneously. Copyright © 2017 John Wiley & Sons, Ltd and ERP Environment     

Is the division of labour limited by the extent of the market? Evidence from French cities

This paper provides supportive evidence to the notion that the division of labour is limited by the extent of the (local) market. We first propose a theoretical model. Its main prediction is that scarce specialists occupations are over-represented in large cities. Using census data for French cities, we find strong empirical support for this prediction.