Learning In A Constellation of Interconnected Practices: Canon or Dissonance?

In this paper we argue that the learning of safety in a constellation of communities of practice is mediated by comparison among the perspectives of the world embraced by the co‐participants in the production of this practice. Our discussion is based on two empirical research projects in which we investigated the accounts of the causes of accidents provided by the members of three different communities of practice (engineers, site foremen and main contractors), in a medium sized building firm. In the paper we suggest that comparison among perspectives is made possible by a discursive practice targeted on the alignment of elements both mental and material, within mutually accountable discursive positions. These alignments are provisional and unstable, they produce tensions, discontinuities and incoherence (cacophony) just as much as they produce order and negotiated meanings (consonance).     

Distribution Dynamics and Nonlinear Growth

This paper extends the distribution dynamics approach to the study of the shape of the growth process of a cross-section of countries. We first identify some empirical implications of a nonlinear Solovian growth model with multiple equilibria. These implications are then tested by a novel definition of the state space, which jointly considers income and growth rate. The main findings are that nonlinearity is a salient feature of the overall picture, and that the cross-section dynamics is compatible with the existence of multiple equilibria. We also discuss how the hypothesis of conditional convergence may be challenged in the light of our results.     

Firms’ exporting and importing activities: is there a two-way relationship?

The literature on firm heterogeneity and trade has highlighted that most trading firms tend to engage in both importing and exporting activities. This paper provides some evidence that helps understanding to what extent this is the result of a two-way relationship. Using firm-level data for a group of 27 Eastern European and Central Asian countries from the World Bank Business Environment and Enterprise Performance Survey (BEEPS) over the period 2002–2008, we estimate a bivariate probit model of exporting and importing. After controlling for size (and other firm-level characteristics) we find that firms’ exporting activity does not increase the probability of importing, while the latter has a positive effect on foreign sales. This effect is mainly channeled through an increase in firm productivity and product innovation.     

Time‐Varying Spot and Futures Oil Price Dynamics

In this paper, we investigate the role of crude oil spot and futures prices in the process of price discovery by using daily data over the period from January 1992 to September 2012. We provide evidence that futures markets play a more important role than spot markets, but their relative contributions turn out to be highly unstable, especially for the most deferred contracts. Furthermore, considering the time‐varying dynamics provides evidence of a smaller role for futures markets and a greater role for fundamental factors in driving oil prices during the global financial turmoil of 2007–2008. The implications of the main results for hedging and forecasting crude oil spot prices are also discussed.     

Collective action clauses: How do they affect sovereign bond yields?

We study the effects of the adoption of collective action clauses (CACs) on government bond yields by exploiting secondary market data on sovereign bonds quoted in international markets from March 2007 to April 2011. CACs are assessed security by security. Using a panel data approach, we find a U-shaped effect of CACs on yields according to the credit rating of the issuer. While the impact is negligible for the highest ratings, a significant yield discount emerges for mid-range ratings, which is smaller for bad ratings and possibly insignificant for the worst ratings. This relationship appears fairly robust across a number of checks. This evidence may reflect the fact that CACs are valuable because they help with orderly restructuring unless the perceived probability of default is too small. Nevertheless, at low ratings, this effect can be weakened by an increasing risk of moral hazard.     

A first look at online reputation on Airbnb,where every stay is above average

Marketing Letters - Judging by the millions of reviews left by guests on the Airbnb platform, this trusted community marketplace for accommodations is fulfilling its mission of matching travelers...     

Distribution of wealth and incomplete markets: Theory and empirical evidence

This paper analyses the equilibrium distribution of wealth in an economy where firms’ productivities are subject to idiosyncratic shocks, returns on factors are determined in competitive markets, households have linear consumption functions and government imposes taxes on capital and labour incomes and equally redistributes the collected resources to households. The equilibrium distribution of wealth is explicitly calculated and its shape crucially depends on market incompleteness. With incomplete markets it follows a Paretian law in the top tail and the Pareto exponent depends on the saving rate, on the net return on capital, on the growth rate of population, and on portfolio diversification. The characteristics of the labour market crucially affects the bottom tail, but not the upper tail of the distribution of wealth in the case of completely decentralized labour market. The analysis also suggests a positive relationship between growth and wealth inequality. The theoretical predictions find a corroboration in the empirical evidence of United States in the period 1989-2004.     

Over the ROC methodology: Productivity,economic size and firms’ export thresholds

We identify the minimum combinations of productivity and “economic size” that Italian manufacturing firms need to achieve in order to access international markets. These “export thresholds” are estimated by applying, for the first time in economics, the ROC (receiver operating characteristics) methodology. In this way, we detect a model‐based (rather than a subjectively determined) cut‐off that allows to identify exporters and nonexporters and provides a measure of each firm’s distance from the export threshold. This methodology also paves the way to investigate other determinants of thresholds, thus helping to design more effective policy interventions to reduce barriers to trade.     

Optimal Portfolio Choice Under Decision‐Based Model Combinations

We propose a density combination approach featuring combination weights that depend on the past forecast performance of the individual models entering the combination through a utility‐based objective function. We apply this model combination scheme to forecast stock returns, both at the aggregate level and by industry, and investigate its forecasting performance relative to a host of existing combination methods, both within the class of linear and time‐varying coefficients, stochastic volatility models. Overall, we find that our combination scheme produces markedly more accurate predictions than the existing alternatives, both in terms of statistical and economic measures of out‐of‐sample predictability. Copyright © 2016 John Wiley & Sons, Ltd.