Supply Determinants of Mining Companies: Evidence for Gold and other Minerals in South Africa

Supply determinants of mining companies have been identified in several factors, with no consensus on their relative importance. These factors, which include mineral commodity prices, the institutional framework, geological characteristics, the scale of mine operations, and specific features of the controlling holdings, can influence the objectives of the mines, and their ability to achieve these objectives. Following a brief overview of alternative literature hypotheses concerned with mineral supply determinants, statistical and econometric analyses are applied to partly pooled cross-mine data over the period 1984–95, for gold and other major export minerals in South Africa. — Des déterminants de l’offre des sociétés minières ont été identifiés dans différents facteurs sans qu’un consensus se dégage quant à leur importance relative. Ces facteurs, au nombre desquels figurent les prix des produits minéraux, le cadre institutionnel, les caractéristiques géographiques, la taille de l’exploitation minière et les caractéristiques de la société de holding majoritaire, peuvent influer sur les objectifs des mines et sur leur aptitude à atteindre ces objectifs. Après une brève revue des hypothèses sous-tendant diverses théories relatives aux déterminants de l’offre des produits minéraux, une analyse statistique et économétrique est effectuée à partir de données partiellement communes, portant sur la période 1984–95, concernant l’or et d’autres importants produits minéraux d’exportation en Afrique du Sud.     

An organizational culture for all seasons? How cultural type dominance and strength influence different performance goals

Organizational culture might influence results, especially in public healthcare organizations characterized by strong professional control. This study investigates whether a specific culture type is most effective in fostering performances. We assess organizational culture through Competing Values Framework and use multivariate regression analysis to test the relationship between dominant culture and competitiveness and financial results. Based on 529 responses from senior managers of 59 organizations, we found that dominant rational and hierarchical culture types are associated, respectively, with higher competitiveness and better financial results. Enhancing a specific performance dimension might require cultural changes aimed to align values with targeted results.     

Selecting structural innovations in DSGE models

Dynamic stochastic general equilibrium (DSGE) models are typically estimated assuming the existence of certain structural shocks that drive macroeconomic fluctuations. We analyze the consequences of estimating shocks that are “nonexistent” and propose a method to select the economic shocks driving macroeconomic uncertainty. Forcing these nonexisting shocks in estimation produces a downward bias in the estimated internal persistence of the model. We show how these distortions can be reduced by using priors for standard deviations whose support includes zero. The method allows us to accurately select shocks and estimate model parameters with high precision. We revisit the empirical evidence on an industry standard medium‐scale DSGE model and find that government and price markup shocks are innovations that do not generate statistically significant dynamics.     

Updates management in mobile applications: iTunes versus Google Play

This paper focuses on a specific strategy that developers of mobile applications may use to stimulate demand: The release of updates. We develop a theoretical analysis that shows that developers have incentives to release updates when experiencing a drop in performance. The predictions of the model are then tested using an unbalanced panel of top 1,000 apps in iTunes and Google Play for five European countries. We estimate that while in iTunes the release of an update stimulates a 26% increase in download growth, in Google Play updates play a less significant role. This difference is partly due to systematic differences in apps and in developers operating in the two stores (“selection effect”), and partly to a lack of quality control on apps and updates in Google Play (“quality check effect”). These findings highlight the crucial importance of an appropriate management of updates as well as the relevance of institutional characteristics of the app stores.     

Gender differences in productivity rewards: the role of human capital

In this paper, we evaluate the gender wage gap component due to differences in characteristics’ rewards in Italy. The main focus is on the relationship between human capital characteristics and gender differences in rewards. We propose a methodology that combines the quantile regression analysis with non-parametric procedures for the estimation of the probability density functions of reward differentials in order to evaluate the evolution of the gap due to human capital characteristics. The analysis is carried out on Italian data taken from the latest available cross-section of the European Community Household Panel (2001). Our study suggests that education can be a good productivity signal and helps reduce the range of the gap; furthermore, highly educated women experience lesser gender-based pay differences as the length of the employment relationship increases.     

Socially responsible and conventional investment funds: performance comparison and the global financial crisis

We investigate the performance of socially responsible funds (SRFs) and conventional funds (CFs) in different market (geographical area and class size) segments during the period 1992–2012. From an unbalanced sample of more than 22 000 funds, we define a matched sample using a beta-distance measure to match any SRF with the ‘nearest neighbour’ CF in terms of sensitivity to risk factors. Using this matching approach and a recursive analysis, we identify several switch points in the lead/lag relationship between the two investment styles over time in different market segments. A relevant finding of our analysis is that SRFs played an ‘insurance role’ outperforming CFs during the 2007 global financial crisis.     

Myopia and monetary equilibria

In an infinitely lived, representative individual economy, important properties of competitive equilibria, such as determinacy and the non-existence of monetary equilibria, are not robust to the introduction of myopia. An individual is myopic if, at each date, he plans consumption only for that date and few periods that immediately follow; that is, his planning horizon, n, is finite. Equilibria with myopia can display real indeterminacy and allow for monetary as well as non-monetary steady states; thus, they share some of the features of equilibria in economies of overlapping generation. The equilibrium price dynamics (but not the consumption dynamics) of an exchange economy with extreme myopia, n = 1, are identical to the dynamics of an overlapping generation economy with two-period lives.