Voting after the bombing: Can terrorist attacks change the outcome of democratic elections?

Economists have recently turned their attention to the effects of terrorism. One much debated effect of terrorist attacks is its impact on the results of democratic elections. We use the electoral consequences of the terrorist attacks of the 11-M in Madrid to analyze this issue. We consider this particular experiment since the attack took place only three days before the 2004 Congressional Election, which allows the use of credible identification criteria. In particular, we use the advance voting by Spanish residents abroad, who cast their vote before the terrorist attack, to identify the effect of the bombing. We exploit this macabre natural experiment to run a difference-in-differences estimation using data on three consecutive Congressional elections. Our empirical results indicate that a terrorist attack can have a large impact on the outcome of democratic elections.

Sacral fusion as an aid in age estimation

The degree of fusion at the anterior aspect of the sacral vertebrae has been scored in 242 male and female skeletons from the Lisbon documented collection, ranging in age from 16 to 59 years old. Statistical tests indicate a sex difference towards earlier fusion in young females compared with young males, as well as a clear association between degree of fusion and age. Similar results have been found in documented skeletal samples from Coimbra and Sassari, and the recommendations stated by these authors regarding age estimation have been positively tested in the Lisbon collection. Although more research from geographically diverse samples is required, a general picture of the pattern of sacral fusion and its associations with age and sex is emerging. We also provide a practical example of the usefulness of the sacrum in age estimation in a forensic setting, a mass grave from the Spanish Civil War. It is concluded that the scoring of the degree of fusion of the sacral vertebrae, specially of S1-2, can be a simple tool for assigning skeletons to broad age groups, and it should be implemented as another resource for age estimation in the study of human skeletal remains.

Mergers and difference-in-difference estimator : why firms do not increase prices?

Difference-in-Difference (DiD) methods are being increasingly used to analyze the impact of mergers on pricing and other market equilibrium outcomes. Using evidence from an exogenous merger between two retail gasoline companies in a specific market in Spain, this paper shows how concentration did not lead to a price increase. In fact, the conjectural variation model concludes that the existence of a collusive agreement before and after the merger accounts for this result, rather than the existence of efficient gains. This result may explain empirical evidence reported in the literature according to which mergers between firms do not have significant effects on prices.

The long term effects of legalizing divorce on children

We estimate the effect of divorce legalization on the long-term well-being ofchildren. Our identification strategy relies on exploiting the different timing of divorcelegalization across European countries. Using European Community Household Paneldata, we compare the adult outcomes of cohorts who were raised in an environmentwhere divorce was banned with cohorts raised after divorce was legalized in the samecountry. We also have control countries where all cohorts were exposed (or notexposed) to divorce as children, thus leading to a difference-in-differences approach. Wefind that women who grew up under legal divorce have lower earnings and income aswell as worse health as adults compared with women who grew up under illegal divorce.These effects are not found for men. We find no effects of divorce legalization onchildren s family formation or dissolution patterns.

The risk of divorce and household saving behavior

We analyze the impact of an increase in the risk of divorce on the savingbehaviour of married couples. From a theoretical perspective, the expected sign of theeffect is ambiguous. We take advantage of the legalization of divorce in Ireland in 1996as an exogenous increase in the likelihood of marital dissolution. We analyze the savingbehaviour over time of couples who were married before the law was passed. We proposea difference-in-differences approach where we use as comparison groups either marriedcouples in other European countries (not affected by the law change), or Irish familieswho did not experience a significant increase in the expected risk of divorce (such as veryreligious families, or single individuals). Our results suggest that the increase in the riskof divorce brought about by the law was followed by an increase in the propensity to saveof married couples, consistent with a rise in precautionary savings interpretation. Anincrease in the risk of marital dissolution of about 40 percent led to a 7 to 13 percent risein the proportion of married couples reporting positive savings.

Finance versus costs for teaching hospitals in Spain

In this paper we analyse the observed systematic differences incosts for teaching hospitals (THhenceforth) in Spain. Concernhas been voiced regarding the existence of a bias in thefinancing of TH s has been raised once prospective budgets arein the arena for hospital finance, and claims for adjusting totake into account the legitimate extra costs of teaching onhospital expenditure are well grounded. We focus on theestimation of the impact of teaching status on average cost. Weused a version of a multiproduct hospital cost function takinginto account some relevant factors from which to derive theobserved differences. We assume that the relationship betweenthe explanatory and the dependent variables follows a flexibleform for each of the explanatory variables. We also model theunderlying covariance structure of the data. We assumed twoqualitatively different sources of variation: random effects andserial correlation. Random variation refers to both general levelvariation (through the random intercept) and the variationspecifically related to teaching status. We postulate that theimpact of the random effects is predominant over the impact ofthe serial correlation effects. The model is estimated byrestricted maximum likelihood. Our results show that costs are 9%higher (15% in the case of median costs) in teaching than innon-teaching hospitals. That is, teaching status legitimatelyexplains no more than half of the observed difference in actualcosts. The impact on costs of the teaching factor depends on thenumber of residents, with an increase of 51.11% per resident forhospitals with fewer than 204 residents (third quartile of thenumber of residents) and 41.84% for hospitals with more than 204residents. In addition, the estimated dispersion is higher amongteaching hospitals. As a result, due to the considerable observedheterogeneity, results should be interpreted with caution. From apolicy making point of view, we conclude that since a higherrelative burden for medical training is under public hospitalcommand, an explicit adjustment to the extra costs that theteaching factor imposes on hospital finance is needed, beforehospital competition for inpatient services takes place.

Social differences in avoidable mortality between small areas of 15 European cities: an ecological study

Health and inequalities in health among inhabitants of European cities are of major importance for European public health and there is great interest in how different health care systems in Europe perform in the reduction of health inequalities. However, evidence on the spatial distribution of cause-specific mortality across neighbourhoods of European cities is scarce. This study presents maps of avoidable mortality in European cities and analyses differences in avoidable mortality between neighbourhoods with different levels of deprivation. Methods: We determined the level of mortality from 14 avoidable causes of death for each neighbourhood of 15 large cities in different European regions. To address the problems associated with Standardised Mortality Ratios for small areas we smooth them using the Bayesian model proposed by Besag, York and Mollié. Ecological regression analysis was used to assess the association between social deprivation and mortality. Results: Mortality from avoidable causes of death is higher in deprived neighbourhoods and mortality rate ratios between areas with different levels of deprivation differ between gender and cities. In most cases rate ratios are lower among women. While Eastern and Southern European cities show higher levels of avoidable mortality, the association of mortality with social deprivation tends to be higher in Northern and lower in Southern Europe. Conclusions: There are marked differences in the level of avoidable mortality between neighbourhoods of European cities and the level of avoidable mortality is associated with social deprivation. There is no systematic difference in the magnitude of this association between European cities or regions. Spatial patterns of avoidable mortality across small city areas can point to possible local problems and specific strategies to reduce health inequality which is important for the development of urban areas and the well-being of their inhabitants

Parametric and semiparametric estimation of sample selection models: an empirical application to the female labour force in Portugal

This comment corrects the errors in the estimation process that appear in Martins (2001). The first error is in the parametric probit estimation, as the previously presented results do not maximize the log-likelihood function. In the global maximum more variables become significant. As for the semiparametric estimation method, the kernel function used in Martins (2001) can take on both positive and negative values, which implies that the participation probability estimates may be outside the interval [0,1]. We have solved the problem by applying local smoothing in the kernel estimation, as suggested by Klein and Spady (1993).

Gender gaps in performance: Evidence from young lawyers

This paper documents and studies the gender gap in performance among associatelawyers in the United States. Unlike most high-skilled professions, the legal professionhas widely-used objective methods to measure and reward lawyers' productivity: thenumber of hours billed to clients and the amount of new-client revenue generated. Wefind clear evidence of a gender gap in annual performance with respect to bothmeasures. Male lawyers bill ten-percent more hours and bring in more than double thenew-client revenue. We show that the differential impact across genders in the presenceof young children and the differences in aspirations to become a law-firm partneraccount for a large part of the difference in performance. These performance gaps haveimportant consequences for gender gaps in earnings. While individual and firmcharacteristics explain up to 50 percent of earnings gap, the inclusion of performancemeasures explains most of the remainder.

Banks and development: Jewish communities in the Italian Renaissance and current economic performance

Are differences in local banking development long-lasting? Do they affect long-term economic performance?I answer these questions by relying on an historical development that occurred in Italian cities during the 15thcentury. A sudden change in the Catholic doctrine had driven the Jews toward money lending. Cities thatwere hosting Jewish communities developed complex banking institutions for two reasons: first, the Jews werethe only people in Italy who were allowed to lend for a profit and, second, the Franciscan reaction to Jewishusury led to the creation of charity lending institutions, the Monti di Pietà, that have survived until today andhave become the basis of the Italian banking system. Using Jewish demography in 1500 as an instrument, Iprovide evidence of (1) an extraordinary persistence in the level of banking development across Italian cities (2)large effects of current local banking development on per-capita income. Additional firm-level analyses suggestthat well-functioning local banks exert large effects on aggregate productivity by reallocating resources towardmore efficient firms. I exploit the expulsion of the Jews from the Spanish territories in Italy in 1541 to arguethat my results are not driven by omitted institutional, cultural and geographical characteristics. In particular,I show that, in Central Italy, the difference in current income between cities that hosted Jewish communitiesand cities that did not exists only in those regions that were not Spanish territories in the 16th century.

Lag-one autocorrelation in short series: Estimation and hypothesis testing

In the first part of the study, nine estimators of the first-order autoregressive parameter are reviewed and a new estimator is proposed. The relationships and discrepancies between the estimators are discussed in order to achieve a clear differentiation. In the second part of the study, the precision in the estimation of autocorrelation is studied. The performance of the ten lag-one autocorrelation estimators is compared in terms of Mean Square Error (combining bias and variance) using data series generated by Monte Carlo simulation. The results show that there is not a single optimal estimator for all conditions, suggesting that the estimator ought to be chosen according to sample size and to the information available of the possible direction of the serial dependence. Additionally, the probability of labelling an actually existing autocorrelation as statistically significant is explored using Monte Carlo sampling. The power estimates obtained are quite similar among the tests associated with the different estimators. These estimates evidence the small probability of detecting autocorrelation in series with less than 20 measurement times.

Assessing positive mental health in people with chronic physical health problems: correlations with socio-demographic variables and physical health status

Background: A holistic perspective on health implies giving careful consideration to the relationship between physical and mental health. In this regard the present study sought to determine the level of Positive Mental Health (PMH) among people with chronic physical health problems, and to examine the relationship between the observed levels of PMH and both physical health status and socio-demographic variables. Methods: The study was based on the Multifactor Model of Positive Mental Health (Lluch, 1999), which comprises six factors: Personal Satisfaction (F1), Prosocial Attitude (F2), Self-control (F3), Autonomy (F4), Problem-solving and Self-actualization (F5), and Interpersonal Relationship Skills (F6). The sample comprised 259 adults with chronic physical health problems who were recruited through a primary care center in the province of Barcelona (Spain). Positive mental health was assessed by means of the Positive Mental Health Questionnaire (Lluch, 1999). Results: Levels of PMH differed, either on the global scale or on specific factors, in relation to the following variables: age: global PMH scores decreased with age (r=-0.129; p=0.038); b) gender: men scored higher on F1 (t=2.203; p=0.028) and F4 (t=3.182; p=0.002), while women scored higher on F2 (t -3.086; p=0.002) and F6 (t=-2.744; p=0.007); c) number of health conditions: the fewer the number of health problems the higher the PMH score on F5 (r=-0.146; p=0.019); d) daily medication: polymedication patients had lower PMH scores, both globally and on various factors; e) use of analgesics: occasional use of painkillers was associated with higher PMH scores on F1 (t=-2.811; p=0.006). There were no significant differences in global PMH scores according to the type of chronic health condition. The only significant difference in the analysis by factors was that patients with hypertension obtained lower PMH scores on the factor Autonomy (t=2.165; p=0.032). Conclusions: Most people with chronic physical health problems have medium or high levels of PMH. The variables that adversely affect PMH are old age, polypharmacy and frequent consumption of analgesics. The type of health problem does not influence the levels of PMH. Much more extensive studies with samples without chronic pathology are now required in order to be able to draw more robust conclusions.

Effects of the 80 km/h and variable speed limits on air pollution in the metropolitan area of Barcelona

In 2008 the regional government of Catalonia (Spain) reduced the maximum speed limit on several stretches of congested urban motorway in the Barcelona metropolitan area to 80 km/h, while in 2009 it introduced a variable speed system on other stretches of its metropolitan motorways. We use the differences-in-differences method, which enables a policy impact to be measured under specific conditions, to assess the impact of these policies on emissions of NOx and PM10. Empirical estimation indicate that reducing the speed limit to 80 km h-1 causes a 1.7 to 3.2% increase in NOx and 5.3 to 5.9% in PM10. By contrast, the variable speed policy reduced NOx and PM10 pollution by 7.7 to 17.1% and 14.5 to 17.3%. As such, a variable speed policy appears to be a more effective environmental policy than reducing the speed limit to a maximum of 80 km/h.

Epidemiology of measles virus outbreaks in Catalonia: importance of immunization in the elimination era

Eradicating measles represents a major public health achievement, yet outbreaks still occur in territories where endemic measles virus (MV) had been eliminated. In Catalonia from the year 2000 cases have occurred as isolated cases or small outbreaks, both linked to imported cases up to the end of 2006 when a large outbreak started out affecting mainly children ≤15m. In consequence, immunization schedule was amended lowering first dose to 12m. Again new MV importations from neighboring countries triggered another outbreak on November 2010 with a different age distribution sparing small children from infection. Differences in incidence (IR), rate ratio (RR) and 95% CI and hospitalization rate (HR) by age group were determined. Statistic z was used for comparing proportions. Total number of confirmed cases was 305 vs 381 in 2006; mean age 20 yrs (SD 14.8yrs; 3m -51yrs) vs 15m (SD13.1yrs; 1m-50yrs). Highest proportion of cases was set in ≥25yrs (47%) vs 24.2% in 2006 (p<0.001). Difference in IR for ≤ 15m was statistically significant (49/100,000 vs 278.2/100,000; RR:3.9; 95%CI 2.9-5.4) and in HR 30.2% vs 15.7% (p<0.001). The change of the month of administration of the first dose proved successful. Given the current epidemiological situation, continued awareness and efforts to reach young adult population are needed to stop the spread of the virus.

Epidemiology of measles virus outbreaks in Catalonia: importance of immunization in the elimination era

Eradicating measles represents a major public health achievement, yet outbreaks still occur in territories where endemic measles virus (MV) had been eliminated. In Catalonia from the year 2000 cases have occurred as isolated cases or small outbreaks, both linked to imported cases up to the end of 2006 when a large outbreak started out affecting mainly children ≤15m. In consequence, immunization schedule was amended lowering first dose to 12m. Again new MV importations from neighboring countries triggered another outbreak on November 2010 with a different age distribution sparing small children from infection. Differences in incidence (IR), rate ratio (RR) and 95% CI and hospitalization rate (HR) by age group were determined. Statistic z was used for comparing proportions. Total number of confirmed cases was 305 vs 381 in 2006; mean age 20 yrs (SD 14.8yrs; 3m -51yrs) vs 15m (SD13.1yrs; 1m-50yrs). Highest proportion of cases was set in ≥25yrs (47%) vs 24.2% in 2006 (p<0.001). Difference in IR for ≤ 15m was statistically significant (49/100,000 vs 278.2/100,000; RR:3.9; 95%CI 2.9-5.4) and in HR 30.2% vs 15.7% (p<0.001). The change of the month of administration of the first dose proved successful. Given the current epidemiological situation, continued awareness and efforts to reach young adult population are needed to stop the spread of the virus.