The economic returns to schooling for Italian men. An evaluation based on instrumental variables

We study the relationship between (log) hourly earnings and schooling for male household heads in Italy, using cross-sectional data from the 1993 and 1995 waves of the Bank of Italy (BI) survey on the income and wealth of Italian households. In line with international evidence, we find that OLS under-estimate the return to schooling. When the endogeneity of schooling is taken into account, the return to an additional year in school increases from 4.8% to 5.6%. This estimate is lower than the estimates tabulated by Card [Card, D., 1994. Earnings, Schooling and Ability Revisited. NBER Working Paper no. 4832.] for the United States. We also find evidence that this return increases with higher levels of educational attainment.     

Some Unintended Consequences of Parallel Trade in Pharmaceuticals

It is widely argued that international arbitrage, or parallel trade (PT), in patented drugs may increase consumer surplus in the relevant countries but at the expense of R&D investment. We show how the effects of PT depend on the vertical contract (linear pricing or dual pricing) between the manufacturer and the foreign licensee or distributor and on whether and how drug prices are regulated and reimbursed. We find that, contrary to what policy makers generally predict, we should be more concerned with the impact of PT on aggregate consumer surplus than on R&D investment. Copyright © 2014 John Wiley & Sons, Ltd.     

Assessment of meaningful change in routine outcome measurement (ROM) with a combination of a longitudinal and a ‘classify and count’ approach

To assess significant changes of health status in people receiving health care, distribution-based and anchor-based methods have been proposed. However, there is no real consensus on what method is the best for evaluating clinically meaningful change. To maximize the internal and external validity of outcome assessment, we propose combining two approaches as recommended by recent practical guidelines on this field. Specifically, we suggest applying longitudinal hierarchical linear models on subgroups of patients showing reliable change and reliable and clinically significant change. This combined approach improved the model’s ability (1) to quantify the magnitude of changes to be reliable and clinically meaningful and (2) to select significant predictors of changes. An empirical application on a prevalence sample of Italian outpatients attending four community mental health services was done. A cross-sectional model and three longitudinal models were applied on the entire study sample and reliable and clinically meaningful change subsamples to investigate the magnitude of change and the predictive effect on outcomes of clinical, socio-demographic and process variables on different patients’ subgroups. Differences were found suggesting that both the statistical method and the sample used to calculate individual changes affect the estimates. The main conclusion is that ignoring the longitudinal data structure or including patients with unreliable change at the follow-up might result in misleading inferences that can alter the real magnitude of changes and the contributions of predictors. The approach proposed provides robust feedback to clinicians on clinically significant change and can be recommended in outcome studies and research.     

Covered interest arbitrage profits: The role of liquidity and credit risk

We study the profitability of Covered Interest Parity (CIP) arbitrage violations and their relationship with market liquidity and credit risk using a novel and unique dataset of tick-by-tick firm quotes for all financial instruments involved in the arbitrage strategy. The empirical analysis shows that positive CIP arbitrage deviations include a compensation for liquidity and credit risk. Once these risk premia are taken into account, small arbitrage profits only accrue to traders who are able to negotiate low trading costs. The results are robust to stale pricing and the nonsynchronous trading occurring in the markets involved in the arbitrage strategy.     

Immigration Policy,Self‐selection,and the Quality of Immigrants*

This paper investigates the effects of immigration quotas on the average quality of immigrants by developing a human capital migration model where efficiency in migration depends on skills and emigration rates are higher among skilled workers. Studying the joint determination of the domestic level of wages and immigrants' self‐selection, we find a negative relationship between the wage level and the percentage of educated workers among immigrants, which results in a nonstandard downward‐sloping labor supply. In our framework, a higher quota increases the skill mix of immigrants through its negative effect on wages and raises aggregate national income.     

Equilibrio e relazione distributiva in un modello di Sraffa con tassi di profitto eterogenei

Si considera un modello di Sraffa a produzione semplice nel quale l'ipotesi di uniformità del saggio di profitto è sostituita con quella di saggi di profitto eterogenei ma in rapporto costante tra di loro. Per tale modello vengono studiati l'esistenza di soluzioni, la costanza dei prezzi rispetto alle variabili distributive ed il legame funzionale tra queste, con speciale riguardo al caso lineare.

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Summary This note deals with the well-known Sraffa's model of exchange for a simple production economy in the case where the sector profit rates bear constant proportions to each other. Some formal results are presented on the equilibria of the model, both in normal and in vertical integrated form, on the dependence, implicitly defined by the model, of the prices vector and of the wage rate on the profit parameter, and about the concepts of (generalized) standard productions and uniform composition of capital.

     

Measuring the Returns to Networking and the Accumulation of Social Capital: Any Evidence of Bonding,Bridging, or Linking?

This article presents analyses of individual investment in social capital using both the British Household Panel Survey (BHPS) and the UK Time Use Survey (2000) (UKTUS). We suggest a general theoretical framework that could possibly explain individual investment in various forms of social networking. Measures of social capital are then constructed in an attempt to capture the extent of individual investment in bonding, bridging, and linking networks. These measures, together with other socioeconomic indicators, are used as explanatory factors in wage equations, estimated using ordered probit, OLS, and instrumental variable approaches. We are unable to identify any consistent returns from investment in bonding and bridging networks. In contrast, the evidence suggests that any returns to investment in the development of linking social capital simply derive from the positive signals that group membership may transmit to potential employers. Our results underline the contrast between studies that consider social capital as an attribute of communities, as opposed to individuals, in that we find a negative return to social activity at the level of the individual.     

Risk parity portfolio optimization under a Markov regime-switching framework

We formulate and solve a risk parity optimization problem under a Markov regime-switching framework to improve parameter estimation and to systematically mitigate the sensitivity of optimal portfolios to estimation error. A regime-switching factor model of returns is introduced to account for the abrupt changes in the behaviour of economic time series associated with financial cycles. This model incorporates market dynamics in an effort to improve parameter estimation. We proceed to use this model for risk parity optimization and also consider the construction of a robust version of the risk parity optimization by introducing uncertainty structures to the estimated market parameters. We test our model by constructing a regime-switching risk parity portfolio based on the Fama–French three-factor model. The out-of-sample computational results show that a regime-switching risk parity portfolio can consistently outperform its nominal counterpart, maintaining a similar ex post level of risk while delivering higher-than-nominal returns over a long-term investment horizon. Moreover, we present a dynamic portfolio rebalancing policy that further magnifies the benefits of a regime-switching portfolio.     

Rock around the clock: An agent-based model of low- and high-frequency trading

We build an agent-based model to study how the interplay between low- and high-frequency trading affects asset price dynamics. Our main goal is to investigate whether high-frequency trading exacerbates market volatility and generates flash crashes. In the model, low-frequency agents adopt trading rules based on chronological time and can switch between fundamentalist and chartist strategies. By contrast, high-frequency traders activation is event-driven and depends on price fluctuations. High-frequency traders use directional strategies to exploit market information produced by low-frequency traders. Monte-Carlo simulations reveal that the model replicates the main stylized facts of financial markets. Furthermore, we find that the presence of high-frequency traders increases market volatility and plays a fundamental role in the generation of flash crashes. The emergence of flash crashes is explained by two salient characteristics of high-frequency traders, i.e., their ability to i. generate high bid-ask spreads and ii. synchronize on the sell side of the limit order book. Finally, we find that higher rates of order cancellation by high-frequency traders increase the incidence of flash crashes but reduce their duration.