Growing interest in inequality has generated an outpouring of scholarly research and has brought ... more Growing interest in inequality has generated an outpouring of scholarly research and has brought many discussions on the subject into the public realm. Surprisingly, most of these studies and discussions rely on a narrow set of indicators to measure inequality. Most of the time a single summary measure of inequality is considered: the Gini coefficient. This is surprising not only because there are many ways to measure inequality, but mostly because the Gini coefficient has only limited success in its ability to generate the amount and type of data required to analyze the complex patterns and dynamics of inequality within and across countries. Often, in defense of the use of the Gini coefficient, it is argued that this popular indicator has a readily intuitive interpretation. While from a formal point of view most measures of inequality are closely interrelated, at an intuitive level this interrelationship is rarely highlighted. This paper suggests an intuitive interpretation for the Theil index, a measure of inequality with unique properties that makes it a powerful instrument to produce data and to analyze patterns and dynamics of inequality. Since the potential of the Theil index to generate rich data sets has been analyzed elsewhere , here we will focus on the intuitive interpretation of the Theil index and on its potential for analytical work. The discussion will be accompanied throughout with empirical applications, and concludes with the description of a simple software application that can be used to compute the Theil index at different levels of aggregation of the individuals that compose the distribution. alternatives to the objective measures are what Sen calls normative measures of inequality, which have imbedded some notion of social welfare. Normative measures of inequality include, in some sense, an ethical evaluation of some kind, while objective measures, in themselves, are "ethically" neutral. Objective measures of inequality employ statistical and other types of formulae that account for the relative variation of income among individuals or groups of people.
In this paper we show that inequality and unemployment are related positively across the European... more In this paper we show that inequality and unemployment are related positively across the European continent, within countries, between countries and through time. This contradicts the often-repeated view that unemployment in Europe is attributable to rigid wage structures, high minimum wages and generous social welfare systems. In fact, countries that possess the low inequality such systems produce experience less unemployment than those that do not. Moreover, large inter-country inequalities across Europe aggravate the continental unemployment problem. There is no paradox in low American unemployment. It stems in part from that country's continent-wide programs of redistribution, including the Social Security System, the Earned Income Tax Credit, the federal minimum wage, and a uniform regime of monetary policy geared toward full employment, all of which reduce inter-regional inequality and all of which we recommend for adoption by the European Union.
2008 11th International IEEE Conference on Intelligent Transportation Systems, 2008
This paper presents a proposal for an automatic vehicle detection and classification (AVDC) syste... more This paper presents a proposal for an automatic vehicle detection and classification (AVDC) system. The proposed AVDC should classify vehicles accordingly to the Portuguese legislation (vehicle height over the first axel and number of axels), and should also support profile based classification. The AVDC should also fulfill the needs of the Portuguese motorway operator, Brisa. For the classification based on the profile we propose:he use of Eigenprofiles, a technique based on Principal Components Analysis. The system should also support multi-lane free flow for future integration in this kind of environments. Citation: FERREIRA, Pedro M.; MARQUES, Goncalo; JORGE, Pedro M.; ABRANTES, Arnaldo J.; AMADOR, Antonio -Automatic Vehicle Detection and Classification.
The introduction of broadband in schools provides a new resource for learning but also an opportu... more The introduction of broadband in schools provides a new resource for learning but also an opportunity for distraction. Consequently, broadband use in schools can either increase or reduce students' performance. This paper provides a model that shows how these two effects trade off. We use a rich panel of data with information on broadband use in all schools in Portugal and on students' performance in the 9 th grade national exams to learn how broadband use affects performance. We use a first-differences specification to control for school-specific unobserved effects. We also use a proxy for the quality of the broadband connection as an instrument to control for unobserved time-varying effects. We show that high levels of broadband use in schools in 2008 and 2009 are detrimental for the grades of 9 th grade students. For the average broadband use in schools, grades reduce about 0.76 and 0.67 of a standard deviation in 2008 and 2009, respectively. We also show evidence suggesting that broadband has a negative impact on exam scores regardless of gender, subject or school quality. We also find suggestive evidence that the way schools allow students to use the Internet affects students' performance, in particular, students in schools that block access to websites such as YouTube perform relatively better. Although test scores do not measure all the effects that broadband in schools have on the performance of students throughout life, our results show that the introduction of Internet in schools is a task that deserves careful planning.
... a Pedro Ferreira is a cosmologist at the University of Oxford, UK, and author of The State of... more ... a Pedro Ferreira is a cosmologist at the University of Oxford, UK, and author of The State of the Universe (Phoenix, 2006). ... The interplay between dark energy and the shape of the universe leaves the fate of the cosmos hanging in the balance, warns physicist Pedro Ferreira. ...
... a, Pedro Ferreira is professor of astrophysics at the University of Oxford and a member of th... more ... a, Pedro Ferreira is professor of astrophysics at the University of Oxford and a member of the Oxford Martin School. His website is pedroferreira.co.uk. Available online 8 October 2010. At last we have the tools to test Einstein's ...
This paper analyzes the behavior of the manufacturing industry after the reforms implemented in t... more This paper analyzes the behavior of the manufacturing industry after the reforms implemented in the nineties. We observed if the opening process generated increases in the average productivity of the manufacturing industry. Additionally, we estimated the markup of di®erent industrial sectors and tested if it changes after the trading opening. As expected, estimates for markup showed a non-competition practice in the majority of the sectors. It was also observed an increase in the average productivity and jumps of productivity in the majority of the industrial sector after the reduction of the trade restrictions. There is no signi¯cant indication of fall in the market power after the opening trade, which could point to the existence of other channels responsible for the productivity increase.
The management of upper extremity gunshot wound with soft tissue and bone injuries remains a rema... more The management of upper extremity gunshot wound with soft tissue and bone injuries remains a remarkable problem and often requires sophisticated reconstructive strategies.
Facial fractures are infrequent in children and adolescents, and there are only few reports that ... more Facial fractures are infrequent in children and adolescents, and there are only few reports that review a significant number of patients. The objective of this study was to analyze the pattern of maxillofacial fractures in pediatric patients of Portugal. We reviewed the clinical records of a series of 1416 patients 18 years or younger with facial fractures, treated by the Department of Plastic Reconstructive, Aesthetic and of Maxillofacial Surgery of São João Hospital, Porto, Portugal, between 1993 and 2012. The following parameters were evaluated: age; sex; cause of the accident; hour, day, and month of hospital admission; location and type of fractures; presence and location of associated injuries; treatment methods; length of in-hospital stay; and complications. A total of 2071 fractures were treated. The ratio of boys to girls was 3.1:1. Patients between 16 and 18 years old were the major group (43.9%). Motor vehicle accident was the most common cause of injuries (48.7% of patie...
Growing interest in inequality has generated an outpouring of scholarly research and has brought ... more Growing interest in inequality has generated an outpouring of scholarly research and has brought many discussions on the subject into the public realm. Surprisingly, most of these studies and discussions rely on a narrow set of indicators to measure inequality. Most of the time a single summary measure of inequality is considered: the Gini coefficient. This is surprising not only because there are many ways to measure inequality, but mostly because the Gini coefficient has only limited success in its ability to generate the amount and type of data required to analyze the complex patterns and dynamics of inequality within and across countries. Often, in defense of the use of the Gini coefficient, it is argued that this popular indicator has a readily intuitive interpretation. While from a formal point of view most measures of inequality are closely interrelated, at an intuitive level this interrelationship is rarely highlighted. This paper suggests an intuitive interpretation for the Theil index, a measure of inequality with unique properties that makes it a powerful instrument to produce data and to analyze patterns and dynamics of inequality. Since the potential of the Theil index to generate rich data sets has been analyzed elsewhere , here we will focus on the intuitive interpretation of the Theil index and on its potential for analytical work. The discussion will be accompanied throughout with empirical applications, and concludes with the description of a simple software application that can be used to compute the Theil index at different levels of aggregation of the individuals that compose the distribution. alternatives to the objective measures are what Sen calls normative measures of inequality, which have imbedded some notion of social welfare. Normative measures of inequality include, in some sense, an ethical evaluation of some kind, while objective measures, in themselves, are "ethically" neutral. Objective measures of inequality employ statistical and other types of formulae that account for the relative variation of income among individuals or groups of people.
In this paper we show that inequality and unemployment are related positively across the European... more In this paper we show that inequality and unemployment are related positively across the European continent, within countries, between countries and through time. This contradicts the often-repeated view that unemployment in Europe is attributable to rigid wage structures, high minimum wages and generous social welfare systems. In fact, countries that possess the low inequality such systems produce experience less unemployment than those that do not. Moreover, large inter-country inequalities across Europe aggravate the continental unemployment problem. There is no paradox in low American unemployment. It stems in part from that country's continent-wide programs of redistribution, including the Social Security System, the Earned Income Tax Credit, the federal minimum wage, and a uniform regime of monetary policy geared toward full employment, all of which reduce inter-regional inequality and all of which we recommend for adoption by the European Union.
2008 11th International IEEE Conference on Intelligent Transportation Systems, 2008
This paper presents a proposal for an automatic vehicle detection and classification (AVDC) syste... more This paper presents a proposal for an automatic vehicle detection and classification (AVDC) system. The proposed AVDC should classify vehicles accordingly to the Portuguese legislation (vehicle height over the first axel and number of axels), and should also support profile based classification. The AVDC should also fulfill the needs of the Portuguese motorway operator, Brisa. For the classification based on the profile we propose:he use of Eigenprofiles, a technique based on Principal Components Analysis. The system should also support multi-lane free flow for future integration in this kind of environments. Citation: FERREIRA, Pedro M.; MARQUES, Goncalo; JORGE, Pedro M.; ABRANTES, Arnaldo J.; AMADOR, Antonio -Automatic Vehicle Detection and Classification.
The introduction of broadband in schools provides a new resource for learning but also an opportu... more The introduction of broadband in schools provides a new resource for learning but also an opportunity for distraction. Consequently, broadband use in schools can either increase or reduce students' performance. This paper provides a model that shows how these two effects trade off. We use a rich panel of data with information on broadband use in all schools in Portugal and on students' performance in the 9 th grade national exams to learn how broadband use affects performance. We use a first-differences specification to control for school-specific unobserved effects. We also use a proxy for the quality of the broadband connection as an instrument to control for unobserved time-varying effects. We show that high levels of broadband use in schools in 2008 and 2009 are detrimental for the grades of 9 th grade students. For the average broadband use in schools, grades reduce about 0.76 and 0.67 of a standard deviation in 2008 and 2009, respectively. We also show evidence suggesting that broadband has a negative impact on exam scores regardless of gender, subject or school quality. We also find suggestive evidence that the way schools allow students to use the Internet affects students' performance, in particular, students in schools that block access to websites such as YouTube perform relatively better. Although test scores do not measure all the effects that broadband in schools have on the performance of students throughout life, our results show that the introduction of Internet in schools is a task that deserves careful planning.
... a Pedro Ferreira is a cosmologist at the University of Oxford, UK, and author of The State of... more ... a Pedro Ferreira is a cosmologist at the University of Oxford, UK, and author of The State of the Universe (Phoenix, 2006). ... The interplay between dark energy and the shape of the universe leaves the fate of the cosmos hanging in the balance, warns physicist Pedro Ferreira. ...
... a, Pedro Ferreira is professor of astrophysics at the University of Oxford and a member of th... more ... a, Pedro Ferreira is professor of astrophysics at the University of Oxford and a member of the Oxford Martin School. His website is pedroferreira.co.uk. Available online 8 October 2010. At last we have the tools to test Einstein's ...
This paper analyzes the behavior of the manufacturing industry after the reforms implemented in t... more This paper analyzes the behavior of the manufacturing industry after the reforms implemented in the nineties. We observed if the opening process generated increases in the average productivity of the manufacturing industry. Additionally, we estimated the markup of di®erent industrial sectors and tested if it changes after the trading opening. As expected, estimates for markup showed a non-competition practice in the majority of the sectors. It was also observed an increase in the average productivity and jumps of productivity in the majority of the industrial sector after the reduction of the trade restrictions. There is no signi¯cant indication of fall in the market power after the opening trade, which could point to the existence of other channels responsible for the productivity increase.
The management of upper extremity gunshot wound with soft tissue and bone injuries remains a rema... more The management of upper extremity gunshot wound with soft tissue and bone injuries remains a remarkable problem and often requires sophisticated reconstructive strategies.
Facial fractures are infrequent in children and adolescents, and there are only few reports that ... more Facial fractures are infrequent in children and adolescents, and there are only few reports that review a significant number of patients. The objective of this study was to analyze the pattern of maxillofacial fractures in pediatric patients of Portugal. We reviewed the clinical records of a series of 1416 patients 18 years or younger with facial fractures, treated by the Department of Plastic Reconstructive, Aesthetic and of Maxillofacial Surgery of São João Hospital, Porto, Portugal, between 1993 and 2012. The following parameters were evaluated: age; sex; cause of the accident; hour, day, and month of hospital admission; location and type of fractures; presence and location of associated injuries; treatment methods; length of in-hospital stay; and complications. A total of 2071 fractures were treated. The ratio of boys to girls was 3.1:1. Patients between 16 and 18 years old were the major group (43.9%). Motor vehicle accident was the most common cause of injuries (48.7% of patie...
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