Patent thickets,courts, and the market for innovation

We study how fragmentation of patent rights and the formation of the Court of Appeals for the Federal Circuit (CAFC) affected the duration of patent disputes, and thus the speed of technology diffusion through licensing. We develop a model of patent litigation which predicts faster settlement when patent rights are fragmented and when there is less uncertainty about court outcomes, as was associated with the “pro‐patent shift” of the CAFC. We confirm these predictions empirically using a data set that covers patent suits in U.S. district courts during the period 1975–2000. Finally, we analyze how fragmentation affects total settlement delay, considering both the reduction in dispute duration and the increase in the number of patent negotiations.     

Worker absenteeism and incentives: evidence from Italy

In Italy, employees are fully insured against earning losses due to illness. Since worker's health is not easily verifiable, absenteeism due to illness is considered an empirical proxy for employee shirking. The Bank of Italy Household Survey (SHIW) provides individual data on days of absence. Controlling for personal characteristics and potential determinants of health status and family responsibilities (age, gender, education, marital status, children at home), we show that the nature of employment contracts affects workers' incentives to provide effort: sickness absences, at least partially, hide opportunistic behaviours. The type of occupation and the labour contracts affects workers' behaviour in that more protected and difficult to monitor jobs show significantly higher levels of absenteeism: employees in public sector or in large firms, with permanent contracts or with longer tenure, individuals living in regions with low unemployment rates. Copyright © 2010 John Wiley & Sons, Ltd.     

Engel’s curve and product differentiation: A dynamic analysis of the effects of quality on consumer’s choice

The application of Engel’s Curve in a single-product perspective may dramatically change the role of quality in affecting the dynamics of economic performance. This paper introduces a specification of preferences that regards quality as luxury, and quantity as necessary. The analysis is carried out by using a framework similar to Grossman’s and Helpman ’s (1991), while quality is defined as in Stokey (1988). The resulting consumer’s demand crucially depends on quality. Quality is potentially able to prevent the process, implied by neoclassical models, that leads the value of consumption goods to decline over time. By doing so, quality also affects the consumption bundle shares and the variety-specific consumption growth rates, thus influencing all dynamic quantitative variables of the economy. I thank Professor Beniamino Moro for his guidance and encouragement. I thank Stephen Wright for his comments and suggestions. I have benefited from the support of Alessio Moro, Dario Unali, Debora Fletcher, Emilio Merella, Esteban Jaimovich, Francesca Lamanna, Matteo Bellinzas, Mauro Merella and all my friends. I am also indebted to Professor Cuong Le Van and Professor Stephen Parente for their advice. I thank two anonymous Referees for their useful remarks.     

Competition, human capital and income inequality with limited commitment

We develop a dynamic model with two-sided limited commitment to study how barriers to competition, such as restrictions to business start-up and non-competitive covenants, affect the incentive to accumulate human capital. When contracts are not enforceable, high barriers lower the outside value of ‘skilled workers’ and reduce the incentive to accumulate human capital. In contrast, low barriers can result in over-accumulation of human capital. This can be socially optimal if there are positive spillovers. A calibration exercise shows that this mechanism can account for a sizable portion of cross-country income inequality.     

On the anti-competitive effects of quantity discounts

We analyze the competitive effects of quantity discounts in an asymmetric duopoly. We find that for a sizeable set of parameter values, quantity discounts harm the smaller firm and reduce consumers' surplus. They can even decrease social welfare, i.e. the sum of producers' and consumers' surpluses. However, the circumstances in which quantity discounts may decrease social welfare are limited and difficult to identify in practice.     

Adaptive expectations and cobweb phenomena: Does heterogeneity matter?

This paper studies a cobweb-type commodity market characterized by a strictly monotone demand and supply, in which n types of firms operate. Types differ in a key parameter governing price expectations which are supposed to be adaptive. The unique steady state of the resulting economic dynamics is characterized in terms of stability and the impact of the number of firms types is studied: to this end the notions of structural and behavioural degree of instability, which are introduced in the paper, prove to be crucial in determining whether stability or instability prevail. The case of market integration is also considered and conditions to have stability (or instability) in terms of the original markets' parameters are given. The baseline structure is extended in two directions. The first extension assumes the point of view of an authority who is uncertain about the firms types. In this case the structural degree of instability determines how heterogeneity affects the probability of ending up with a stable outcome. The second extension consists in endogenizing the choice of predictors through a discrete choice-based evolutionary mechanism. In both cases the amount of the heterogeneity and its possible variations play a critical role in shaping the range of possible long-run outcomes of the model.     

Retirement and Healthy Eating

This paper investigates the effect of retirement on healthy eating using data drawn from the Survey of Health, Ageing and Retirement in Europe (SHARE). We estimate the causal effect of retiring from work on daily fruit or vegetable consumption by exploiting policy changes in eligibility rules for early and statutory retirement. Our results show that changes in eating behaviour upon retirement are gender-specific: retirement induces men to reduce healthy eating; it has no effect on women. We further show that, for men, retirement increases the probability of becoming obese.     

Quasi‐Experimental Evidence on the Effects of Health Information on Preventive Behaviour in Europe

We investigate the effect of information on preventive decisions in a quasi‐experimental setting arising from the implementation of local breast cancer screening programmes in Europe. To identify the causal effect of invitation on preventive uptake, we link administrative public data on regional screening policies to individual data from the Survey of Health Ageing and Retirement in Europe (SHARE) and exploit regional variation in the availability of screening policies and in age eligibility criteria. We find home invitation increases mammography uptakes by around 24%. Significant effects are found when at least 50% of the population is reached by the invitation letter. The stock of health information and the ability to process the information received seem to play a significant role, as the effects of invitation are higher among low educated and lower among cognitively impaired women.     

The Impact of Oportunidades on Consumption,Savings and Transfers*

In this paper, we estimate the effect of the Mexican conditional cash transfer programme, Oportunidades, on transfers, savings and consumption for treated households. We find positive effects on consumption of non‐durable and durable goods, an increase in savings coupled with a drop in the number and values of loans, and a reduction of in‐kind transfers received by households in treatment areas. These results are consistent with the existing evidence that conditional cash transfer programmes have beneficial effects in both the short and medium term, but that they partly crowd out private transfers.