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2016 - 2017, The Vector Autoregressive (VAR) Models can be considered as a dynamic multivariate extension of the univariate autoregressive models. This family of models has become very popular in macroeconomics analysis after the work of Sims(1980) and they are widely used in time series literature thanks to their flexibility. As a matter of fact, by setting appropriately a VAR model, we can describe efficiently the dynamics of the economy and provide quite accurate forecasts. During recent years, researchers developed different VAR models with the purpose to represent better the data generating process. Among these, the nonlinear VAR models have gained a central role in macroeconometric analysis in testing the theory, due to their capacity to capture a richer set of dynamics regarding current macroeconomic phenomenons. Depending on the specific model, they can allow, for example, different states (regimes) of the world, to allow the coefficients of the model to vary over time in each time unit, allowing for interactions between variables potentially revealing important information. The first paper included in this thesis is a survey which have the purpose to examine linear and nonlinear VAR models. The second and third papers present two empirical applications of the Interacted Panel VAR Model, which is a new nonlinear methodology we illustrated over the first paper. Specifically, we analyze in both papers the behavior of government spending multiplier when the interest rate is at the Zero Lower Bound (ZLB). This is a highly topical question since the outbreak of Great Recession, given that many policy makers have wondered whether fiscal stimulus would be able to help the economy to recover from recession. In particular, there exist two different and opposite theoretical predictions. New Keynesian DSGE models show that, when the interest rate is at the ZLB, a raise in government spending has a strong and positive impact on the economy. On the other side, theoretical prediction indicate very low multipliers, showing that an increase in government spending does not stimulate private activity. Although there exist many theoretical predictions about the size of government spending multiplier at the ZLB, very few empirical evidences are provided. These two paper aim to shed light on the size of the government spending multiplier at the ZLB. Among the nonlinear VAR models, we choose the Interacted (Panel) VAR Model because it offers an important advantage compared to others nonlinear approaches. Thanks to the interaction term, we are able to investigate among the entire sample. This can be done also within a time varying framework, but it implies a larger number of estimates which requires informative priors. In order to be as more agnostic as possible, we also use a Bayesian approach for inference but with uninformative priors. In the first paper we develop an Interacted VAR Model and conduct our analysis on the United States sample. In order to identify government spending shocks we use the sign restrictions approach, furthermore we use the forecast series of government spending to account for the potential effects of anticipation that can pose serious problems for the identification of government spending shocks. We find that the government spending multiplier ranges between 3.4 and 3.7 at the ZLB, while it ranges from 1.5 to 2.7 away from the ZLB. Then, we develop a Factor-Augmented IVAR (FAIVAR) model with the purpose to address another limited information problem. It confirms our results from a qualitatively point of view. As a matter of fact, the government spending multiplier ranges between 2.0 and 2.1 at the ZLB and between 1.5 and 1.8 away from the ZLB. These results are also in line with some recent studies which predict higher multipliers at the ZLB than in normal times... [edited by author], XVI n.s.

2016 - 2017, The importance of financial institutions as pivotal for the economy is largely acknowledged. Since they provide specific services, such as issuing loans and collecting deposits, and perform a number of peculiar functions, including maturity transformation and risk diversification, banks and financial intermediaries are often referred to as “special”. However, the risks they face are special as well. Being extremely leveraged institutions, banks walk on a very thin thread and, considering that they are nowadays world-wide connected, instability can rapidly spread over the system, even affecting the real economy. Therefore, traditional economic rules are not entirely suitable for banks, which require a particular attention from regulatory authorities and academics. This thesis focuses on two areas of remarkable importance, namely financial stability and banking competition, and develops within three chapters, as explained below. The aim of Chapter 1 is to highlight the relevance of financial stability and competition, also asking why regulators are extremely concerned about the two topics. The second and third chapters, then, start from the above premises with a specific focus on the Italian system. This is the backbone of the thesis: Italy is full of specificities, sometimes difficult to understand completely. Nonetheless, it is desirable that these specificities are protected and encouraged, since, very often, they have proven to be a strength... [edited by Author], XVI n.s. (XXX ciclo)

2014 - 2015, Over the last two decades there has been a proliferation of literature on program evaluation. Many researches in economics look at the causal effect of exposure of units to programs on some outcomes through econometric and statistical analysis. The units are typically economic agents such as individuals, households, markets, firms, counties, states or countries. The programs can be job search assistance programs, educational programs, vouchers, laws or regulations, drug therapies, environmental exposure or technology shocks. Rubin potential outcomes framework seems to be the dominant framework in which the aim is to compare the two potential outcomes for the same unit when he or she is exposed and not exposed to the program (or treatment)1. However, each unit can be only exposed to one levels of program: an individual may enrol or not in a training program or he (or she) may be subjected or not to policy. We can refer to this as the fundamental problem of causal inference (Holland, 1986; Imbens andWooldridge, 2008). The impossibility to compare the same individual at different treatment status induces to resolve the issue thinking in term of counterfactual. We need to compare distinct units at different levels of treatment. This means to compare different physical units or the same physical unit observed at different times. But each individual or unit who chooses to enrol in a program is (by definition) different from that who chooses not to enrol. These differences may invalidate causal comparison of outcomes by treatment status. Indeed, the fear in this econometrics literature is traditionally related to endogeneity, or self-selection, issues2. The simplest case for analysis is when assignment to treatment is randomized, and thus independent from the covariates as well as the potential outcomes. It is straightforward to obtain attractive estimators for the average effect of treatment in randomized experiments (e.g. the difference in means by treatment status). Although there have been some example 1Starting from the seventies, Rubin (1974, 1977, 1978) proposed to interpret the causal effect as comparison of so-called potential outcomes, namely pairs of outcomes define for the same unit given different levels of exposure to the treatment. This represent the dominant approach to the analysis of causal relationship in observational studies known with the label of Rubin Causal Model. 2Many of the initial theoretical studies focused on the use of traditional methods for dealing with endogeneity, such as fixed effect methods from panel data analyses and instrumental variables methods. Subsequently, the econometrics literatures has developed new approaches, requiring fewer functional form and homogeneity assumptions (Imbens and Wooldridge, 2008). 3/ 12 of experimental evaluations, they remain relatively rare in economics. More common is the case where economists analyse data from observational studies. Observational data generally create challenges in estimating causal effects referred to unconfoundedness, exogeneity, conditional independence, or selection on observable characteristics3. Estimation and inference of causal effect under unconfoundedness assumption requires that conditional on observed covariates there are no unobserved factors that are associated both with the assignment and with the potential outcomes4. Without unconfoundedness assumption there is no general approach to estimating treatment effects and various methods have been proposed (for a review, see Imbens and Wooldridge 2008). Where additional data are present in the form of samples of treated and control units before and after the treatment comparisons can be made through a difference-in-difference approach. The simplest setting is one where outcomes are observed for units observed in one of two groups (i.e. treated and control) and in one of two time periods (i.e. pre-treatment and post-treatment). Only units in one of the two groups, in the second time period, are exposed to a treatment. There are no units exposed to the treatment in the first period, and units from control group are never observed to be exposed to the treatment. To estimate the causal effect, the average change over time in the outcomes of control group is subtracted from the change over time in the outcomes of treated group. This double differencing removes biases in second period comparisons between the treatment and control group, that could be the result from permanent differences between those groups, as well as biases from comparisons over time in the treatment group, that could be the result of time trends unrelated to the treatment. Where the assignment of treatment is a deterministic function of covariates, comparisons can be made exploring continuity of average outcomes as a function of covariates. This setting, known as the regression discontinuity design, has a long tradition in statistics though only recently it has attracted much attention in the economics literature5. The basic idea is that assignment to the treatment is determined, either completely or partly, by the value of a predictor (i.e. an individual’s observable characteristic) being on either side of a common threshold. This generates a discontinuity in the conditional probability of receiving the treatment as a function of this particular predictor. Any other characteristic, between elected and unelected individual, is assumed to be smooth. As a result, any discontinuity of the conditional distribution of the outcome, as a function of this covariate at the threshold, is interpreted as evidence of a causal effect of the treatment6. 3For a review on this literature, see Imbens and Wooldridge (2008). 4Unconfoundedness implies that we have a sufficiently rich set of predictors for the treatment indicator, such that adjusting for differences in these covariates leads to valid estimates of causal effect. 5For recent review in the economics literature, see Van der Klaauw (2008), Imbens andWooldridge (2008) and Lee and Lemieux (2010). 6It may be useful to distinguish between two general setting, the sharp and the fuzzy regression discontinuity design. In the sharp regression discontinuity design, the assignment to treatment is a deterministic function of one of the observable covariates. In the fuzzy regression discontinuity design the probability of receiving the treatment 4/ 12 This thesis presents three essays of policy evaluation using the above quasi-experimental approaches. The research covers two different type of policies. On the one hand, we assess the effects on crime induced by a marijuana decriminalization policy exploiting the reforms still ongoing in the United States, on the other hand, we evaluate the impacts of the labour market reforms on labour market outcomes by using the recent changes in Italy occurred after the law 92/2012 (the so-called Fornero reform) like identification tool. Depending on the specific subject, the analysis is carried out from a specific empirical point of view. The first essay sheds light on the relationship between Medical Marijuana Laws and crimes in United States using counties level data. The set of judicial rules on the therapeutic consumption, production and distribution of cannabis at State level—started since 1996 in the United States—is known as Medical Marijuana Law (MML). It recognises the medical value of marijuana and provides a legal defence for patients who used and possessed marijuana under recommendation of a physician. The purpose of policy was the pain reduction for which the States allow doctors to prescribe marijuana as a pain killer also for general complaints related to pain, such as migraines, back pain and other pathologies. But, since the list of illness is quite broad, de facto, MML allows wide possibility for recreational use of marijuana masked like therapeutic consumptions (Chu, 2012). Hence, the assessment of policy on crime seems suitable. The research closely examining the importance of policy dimensions and the timing of the core elements of MMLs. In the U.S. States there have been three main actions that have involved the cannabis use for medical purpose: the mere decriminalization of marijuana, the permission of home cultivation for patients and caregivers, the licence for selling marijuana in authorized dispensaries. We interpret dimensions as design choices of policy maker on legal marijuana market by distinguishing between demand side approach, aimed to merely decriminalize cannabis, and supply side approach, directed to provide legal sources of supply for marijuana. This permits to explain the possible transmission channel trough which Medical Marijuana State Laws can affect crime. We test three possible links between drugs liberalization reforms and crime (i.e. pharmacological, economic, and systemic channels) finding evidence for only one of them (i.e. systemic channel). The analysis uses the Uniform Crime Reporting Program Data (UCR, 2013) which reports the number of arrests by type of offence from 1994 to 2014 at the U.S. county level. Since we have data of treated and control counties before and after the implementation of MML, we employ difference-in-difference approach by considering several types of crime such as violent and property crimes, and also felonies for narcotic possession (i.e. cocaine, heroine need not change from zero to one at the threshold. The design only requires a sufficiently large discontinuity in the probability of assignment to the treatment at the threshold. 5/ 12 etc.). We exploit the assessment of Medical Marijuana Law to highlight an important question in program evaluation concerning the heterogeneity of treatment effect. Even if the average treatment effect is zero, it may be important to establish whether a targeted implementation of intervention or different levels of treatment across the population could affect average outcome. We find that a simple dichotomous indicator of Medical Marijuana Law (i.e. the average treatment effect on all the U.S. States that passed the policy) may mask crucial dynamics underlying the relationship between policy and crime. Assuming a homogeneous impact of policy on crime, regardless the action implemented, the dichotomous indicator of MML captures only the net effect of the regulatory tools put in place by the legislator. On the contrary, the policy decomposition in key dimensions allows to discover different results which suggests a heterogeneous effects on crime according to the specific regulatory actions put in place by the legislator. In detail, for burglaries, larcenies, and cocaine drug possession, the mere application of demand side approach increases the crime in counties that passed the policy compared to counties without MML. While, the joint application of demand and supply approach— which establish legal sources for supply marijuana — may be able to realize a crowding-out effect on these offences. The findings support the idea that the licit competition on the marijuana market, triggered by the policy, could push out the illegal trade decreasing the crime. Finally, we find a net reduction in murders and a net increase in synthetic drug possession for the U.S. counties subject to the Medical Marijuana Law relatively to counties never passed the policy. The second and the third essays assess the impact of law 92/2012, implemented in Italy in 2012 (the so-called Fornero reform), on different labour market outcomes. The law 92/2012 introduced numerous changes regarding employment relationships amending past discipline. First. It substantially changed the discipline concerning the dismissals in firms above 15 employees. The reform established that in case of unfair dismissal, the dismissed worker has no longer the right to be reinstated as in the pre-reform period and receives a monetary compensation that ranges between 12 and 24 months pay. Thus the reform significantly reduces the firing cost borne by large firms. Second. Starting from January 2013, the Fornero reform also changed the discipline on apprenticeships concerning to the minimum duration of contract (no less than six months), the maximum number of apprentices that an employer can hire per each skilled worker (passed from 1:1 to 3:2), and the minimum number of apprentices that an employer must stabilize into permanent contracts for hiring a new apprentice (at least the 30% of apprentices hired in the last 12 months). Third. The Fornero reform implemented a new incentive program in favour of employers that recruit (on fixed-term or open-ended contracts) or stabilize into permanent agreements a worker aged 50 or more years. 6/ 12 The second essay (carried out with Giovanni Pica) estimates the effect of employment protection legislation on the flow of monthly hirings on open ended contracts using the aforesaid labour market reform passed in Italy in 2012. Much empirical research has focused on the effects of dismissal costs on labour market outcomes. The evidence suggests that EPL decreases employment inflows and outflows with little effect on employment and unemployment stocks. The reason is that firing costs act, in expected discounted value, as hiring cost reducing the willingness of the firms to both fire and hire workers (Bentolila and Bertola, 1990; Blanchard and Portugal, 2001). The most recent studies identify the causal impact of employment protection on labour market outcome exploiting within-county variation in EPL either across firms (e.g. of different size) or workers (e.g. of different age and/or tenure). The essay presented is in the line with within-county approach which allows to better control for time-varying unobserved characteristics that may affect labour market outcomes (act as confounding factors) compared to cross-country analyses. The presence of both treated and control firms observed before and after the policy — where the assignment of treatment depends in deterministic way from the number of workers employed — allows to implement a difference-in-difference approach jointly to a regression discontinuity design. We thus exploit the differential law change between firms with more and less than 15 workers comparing hirings in firms just above and below the 15 employee threshold before and after the reform (July 2012). The analysis is based on monthly data drawn from Italian Social Security (INPS) record for the period 2012 and 2014. The data provide information on the number of newly hired workers by firms size, province, sector, contract type, age and gender at a monthly frequency. The findings suggest that the reform raises monthly hirings on open-ended contracts by about 5.1 percentage points. The quantification of results reveals that the reduction of dismissal costs after the reform have induced about 4000 hirings per month in firms with more than 15 workers relative to firms with less than 15 workers. The effect of the reduction in EPL is not homogeneous across workers’ types. The increase seems to be more pronounced for full-time, young, and blue-collar workers. Conversely, we find no significant effect on the number of conversions of temporary contracts into permanent ones. The third essay evaluates the impact of labour policies aimed to improve the job possibilities for workers categorized as vulnerable (particularly in labour markets with stringent employment protection)7. Given the increasingly complicated transition from school to works, the youth appear a group more vulnerable compared to the past. Here the apprenticeship contract performs a crucial role by improving the job possibility and the stability of young workers (Berton et al., 2007; Casale et al., 2014). At the same time, the low employment rates for older workers pushed most OECD countries 7Evidences suggest that labour market prospects for youth and other marginal groups seem to worsen as a consequence of stringent EPL (Allard and Lindert, 2007; Bertola et al., 2007; Skedinger, 2010). 7/ 12 to experiment specific employment protections with the purpose to protect them from unemployment or/and to improve their job finding rates (Chéron et al., 2011). The Fornero reform intervenes by changing the discipline of apprenticeship in Italy and implementing a new incentive program for workers aged 50 or more years. The reform asymmetrically acted on the apprenticeships by changing the discipline in firms with more than 10 employees leaving the rules for firms below 10 unchanged. Likewise, the new incentive program for workers aged 50 or more years, passed with the Fornero reform, cut the hiring costs in firms that recruit workers over-50, leaving unaffected the costs for hiring workers under-50. These discontinuities in the regulation as well as the simultaneous presence of treated and control groups observed before and after the policy allow to implement a difference-in-deference method jointly to a regression discontinuity design. This quasi-experimental method permits to evaluate the causal effect of reform on the monthly hirings of apprentices and workers over-50. We thus exploit the differential law change in apprenticeships between firms with more and less than 10 employees, comparing the hirings and the conversions into open-ended contracts of apprentices in firms just below and above the 10 employees threshold before and after the reform (January 2013). Similarly, we compare the recruitments and the conversions into permanent contracts of workers with more and less 50 years before and after the reform. Also this analysis uses monthly data draw from Italian Social Security (INPS) record for the period 2012 and 2014. The findings suggest that the change in apprenticeships increase the stabilization of apprentices into open-ended contracts by about 3.9 percentage points in firms with more than 10 employees relative to firms with less than 10. We also find a positive association between law 92/2012 and the new recruitments of apprentices by about 7.1 percentage points in firms with more than 10 employees relative to firms with less than 10 employees. The employer incentives for hiring and stabilizing the workers aged 50 or more years positively affect the recruitments into open-ended contracts of workers over-50 relative to workers under-50 by about 1.6 percentage point. We also find a positive association between the incentive program and the hirings into fixed-term contracts of workers over-50 relative to workers under-50. Conversely, we don’t find effects for the conversions into open-ended contracts of workers aged 50 or more years. [edited by author], Proposito della tesi di dottorato, dal titolo “Three Essays on Policy Evaluation”, è quello di sottolineare come l’impatto di una politica (economica e non) possa essere valutato secondo un approccio rigoroso, quasi-sperimentale, quando architettata adeguatamente a tale scopo. A tal proposito, sono mostrati tre esempi di valutazione delle politiche, nel corso dei quali si espongono ed affrontano le principali problematiche legate a questo tipo di esercizio. L'interesse dell'approccio adoperato nella presente tesi è dato dall'ampia utilizzazione del metodo difference-in-difference che consente di stimare, in vari contesti, gli impatti che politiche di differente natura possono avere sulle variabili socio-economiche. Ciascuno degli esercizi di valutazione costituisce un capitolo della tesi. Ogni uno di essi ha comportato una rassegna della letteratura in materia (allo scopo di inquadrare il tema trattato), la ricerca dei dati e l’elaborazione di uno specifico modello econometrico finalizzato all’identificazione del nesso causale. Il primo capitolo valuta l’impatto che le politiche di decriminalizzazione della cannabis per scopi terapeutici (Medical Marijuana Laws), adottate nei singoli Stati degli Stati Uniti, hanno avuto sulla criminalità a livello di contea. L’impatto della riforma è valutato rispetto a differenti tipologie di crimini, tratti dal UCR del FBI, classificabili in reati legati alla persona (i.e. omicidi), alla proprietà (i.e. furti) e all’uso di altre sostanza stupefacenti (i.e. cocaina). Dal lavoro emerge come ciascuno Stato americano si differenzi dagli altri sia per le tempistiche che per le modalità attuative della decriminalizzazione. L’originalità del lavoro sta nello sfruttare questa eterogeneità. Esso, infatti, propone una scomposizione della politica di decriminalizzazione della cannabis in interventi chiave, legati alle specifiche azioni adottate in tema di approvvigionamento e di distribuzione della marijuana. Tale scomposizione permette di identificare come l’impatto sui crimini commessi vari a seconda del timing e delle modalità di approvazione della decriminalizzazione. La scomposizione consente, inoltre, di ipotizzare un possibile canale di trasmissione attraverso il quale la Medical Marijuana Law impatterebbe sui crimini. I risultati empirici suggeriscono che la semplice decriminalizzazione della marijuana avrebbe un impatto positivo sulla criminalità se non accompagnata da (contestuali) interventi finalizzati ad istituire fonti legali di approvvigionamento della sostanza. Il secondo capitolo studia il ruolo che i meccanismi di protezione dell’occupazione (employment protection legislation) esercitano sui flussi in entrata del mercato del lavoro. A tale scopo, il lavoro stima l’impatto sulle assunzioni (e conversioni) in contratti a tempo indeterminato indotto dalla riforma del mercato del lavoro in Italia – legge n. 92 del 2012 (cd. riforma Fornero) – che ha ridotto i costi di licenziamento in carico alle imprese con più di 15 dipendenti, lasciando inalterata la situazione per le imprese con meno di 15 dipendenti. Il lavoro, oltre ad inquadrare la tematica con una rassegna della letteratura, sfrutta l’asimmetrico impatto della riforma (per le imprese appena sopra e appena sotto i 15 dipendenti) per stimare un modello difference-in-difference in un contesto di regression discontinuity design, utilizzando dati mensili INPS. I risultati empirici suggeriscono che la riduzione delle protezioni del lavoro incrementi le assunzioni in contratti a tempo indeterminato. Tale effetto risulta non omogeneo tra i diversi gruppi di lavoratori, mostrandosi più pronunciato per gli assunti full-time, più giovani ed operai. Al contrario, non emerge un chiaro effetto rispetto alle conversioni in contratti a tempo indeterminato. Infine, il terzo capitolo esamina le politiche del lavoro aventi l’obiettivo di aumentare le possibilità occupazionali di categorie ritenute più vulnerabili, quali i giovani lavoratori e gli over-50. A questo scopo, si utilizza la riforma dell’apprendistato e l’introduzione di un nuovo schema di incentivi per i lavoratori over-50, in forza in Italia a partire da gennaio 2013 (legge 92/2012), per stimare l’impatto che tali tipologia di interventi hanno sulle nuove assunzioni (sia a tempo determinato che indeterminato) e sulle conversioni in contratti a tempo indeterminato. Nello specifico, la riforma dell’apprendistato ha introdotto, per le imprese con più di 9 dipendenti, nuovi obblighi di stabilizzazione degli apprendisti assunti ed ha innalzato il rapporto tra gli apprendisti e i lavoratori qualificati presenti in azienda. Al contrario, la riforma lascia inalterata la situazione per le imprese sotto i 10 dipendenti. Lo schema di incentivi per l’assunzione e la stabilizzazione dei lavoratori over-50 consta, invece, in un significativo abbattimento (50 per cento) dei contributi a carico impresa per i lavoratori con più di 50 anni, lasciando inalterata la situazione per i soggetti più giovani. Le suddette circostanze hanno reso possibile l’implementazione di un modello difference-in-difference in un contesto di regression discontinuity design, utilizzando dati mensili INPS. I risultati empirici dimostrano che la riforma dell’apprendistato ha effettivamente favorito la stabilizzazione degli apprendisti in contratti a tempo indeterminato. Lo schema di incentivi per gli over-50 sembrerebbe indurre nuove assunzioni tanto in contratti a tempo indeterminato quanto a tempo determinato. L’effetto sulle conversioni, invece, sembrerebbe trascurabile. [a cura dell'autore], XIV n.s.

2014 - 2015, Il lavoro analizza empiricamente due possibili cause di inefficienza allocativa: l'asimmetria informativa (capitolo 1) e la disuguaglianza nella distribuzione della ricchezza (capitolo 2). Il primo capitolo ha l’obiettivo di valutare la presenza di problemi di azzardo morale nel mercato delle assicurazioni sulla salute. Utilizzando dati “National Longitudinal Survey” (NLSY79), il lavoro considera un campione di individui nati tra il 1957 e il 1964 che vivevano negli Stati Uniti nel momento in cui l'indagine è cominciata (1979). Sono state raccolte circa 13.000 osservazioni, tra uomini e donne di molteplici fasce d'età, con un range temporale che si estende fino al 2012. La disponibilità dei dati tende però a ridursi a seguito della selezione delle variabili rilevanti per l'analisi, raggiungendo una disponibilità media di 8.000 osservazioni. Le variabili selezionate, infatti, riflettendo informazioni sensibili (stato di salute, storia familiare, ecc.) sono maggiormente esposte ai problemi di "mancata risposta". L’ipotesi che viene sottoposta a verifica è che, non sostenendo, o sostenendo solo in parte, spese mediche e diagnostiche, gli individui assicurati tendano a sottoporsi con maggiore frequenza rispetto ai non assicurati a visite mediche specialistiche, configurando in tal modo un comportamento opportunistico. Utilizzando un modello difference-in-difference, il lavoro dimostra che, rispetto ai non assicurati, gli individui assicurati tendono a comportarsi in maniera poco coerente rispetto al proprio stato di salute e rispetto alla propria storia medica passata, sottoponendosi a frequenti visite specialistiche, anche le più disparate. Tale comportamento non risulta giustificato dallo stato di salute o da un aggravamento dello stesso. Gli individui non assicurati, invece, tendono a mantenere un comportamento coerente con il proprio stato di salute. La presenza di azzardo morale risulta evidente confrontando il comportamento degli individui assicurati con il rispettivo controfattuale, costruito ad hocattraverso il modello difference-in-difference. Tale confronto permette inoltre di scindere il problema dell'azzardo morale da quello della selezione avversa. Quest’ultima, infatti, viene registrata separatamente, Due Possibili Cause di Inefficienza Allocativa. Analisi ed Evidenza Empirica 3 confrontando il controfattuale con il comportamento degli individui non assicurati. I risultati sono stati sottoposti a una serie di analisi di robustezza, utilizzando il metodo delle variabili strumentali (IV model) e i metodi ordered probit e tobit model. Tali ultime due analisi risultano opportune e appropriate, considerata la conformazione della variabile dipendente, che si presenta come una variabile multinomiale ordinata, con un massa di osservazioni in zero. I risultati confermano che al variare dello status degli individui, da non assicurato ad assicurato, le visite mediche specialistiche tendono ad aumentare e tende a comprimersi in maniera considerevole la probabilità di non sottoporsi ad alcuna visita medica. Tale comportamento, ancora una volta, risulta svincolato dai problemi di salute degli individui, escludendo quindi che i risultati configurino uno scenario di selezione avversa. Il secondo capitolo analizza il rapporto tra diseguaglianza e crescita attraverso un’analisi panel. Nello specifico è stato utilizzato un fixed effects model con l’obiettivo di valutare la direzionalità tra le due variabili. L’idea del lavoro è che una distribuzione ineguale della ricchezza possa condurre a un inasprimento delle condizioni economiche, e quindi a una minore crescita. A differenza di gran parte della letteratura in materia, il campione su cui sono state condotte le stime è composto di paesi relativamente omogenei tra loro in termini di istituzioni e cultura, quali quelli del Sudamerica e dell'America Centrale. Ciò allo scopo di evitare che l'eterogeneità tra paesi possa inficiare i risultati empirici. I dati utilizzati, principalmente fonte Banca Mondiale, riguardano 10 paesi per un periodo temporale che va dal 1970 al 2013. I risultati ottenuti mostrano che la disuguaglianza costituisce effettivamente un freno alla crescita economica, e ciò sia a causa dell'instabilità politica e sociale, sia a causa della riduzione della domanda interna. Inoltre, attraverso un modello di scomposizione degli effetti fissi (fevd model), si è visto che le variabili geografiche rivestono un ruolo marginale nella relazione tra disuguaglianza e crescita. Ciò può essere ascritto all'omogeneità dei paesi che si è scelto di includere nel campione. I risultati risultano infine Due Possibili Cause di Inefficienza Allocativa. Analisi ed Evidenza Empirica 4 robusti al variare della metodologia applicata: il modello delle variabili strumentali e il modello random effects, implementato a seguito della lettura del test di Hausman, confermano l'esistenza della relazione negativa tra le variabili in esame. [a cura dell'editore], XIV n.s.

2012 - 2013 In this work some aspects of health have been examined. After a short description of the evolution of the concept of health and disease, analysis focused on “Health and Welfare”, “Health and Individual choices” and “Health and Economic Growth”. The analysis of the concept of health and disease has been conducted through the historical reconstruction of philosophical, ethical, personal and social meanings allocated over time to the two terms. They affect the validity of the models and theories used in health care to evaluate individual’s well-being and change individual’s moral obligations, rights and responsibilities and the degree of state intervention. It was easy the systematic comparison between welfare and extra-welfarism, two of the most important theories of the role of the welfare state in the West. Then the attention focused on the analysis of health and individual choices, with a short analysis of the model of Michael Grossman, very important in this field of study to go on and investigate the nature and limits of state on individual decision-making processes, especially on the choice of lifestyle you prefer to follow. Government can implement different measures to encourage healthy behaviors, both through monetary interventions (taxes and subsidies) and non-monetary, such as nudging. According to many supporters of nudging, individual choices, especially related to lifestyle that you decide to follow, often appear irrational. After trying to figure out if what is called "homo economicus", represents the best approximation to the rational behavior of individuals, we have examined main features of nudging, theoretical and policy implications of the theory through a reinterpretation of the model of consumer choice. The work ended with the reinterpretation of the neoclassical growth model where the technology and health have a positive impact on labor productivity with a connected econometric exercise. [edited by Author] XII n.s.

2013 - 2014 The problem of the inefficiency of the judicial system is a very present in Italy. In Italy the average duration of a process is significantly higher than that of the Ocse countries. The excessive length of judgments has meant that the cost incurred by the Italian government for compensation for financial loss for the unreasonable length of the process has assumed alarming proportions. The Italian judicial system is characterized, respect to major European countries, for the high litigation and for the high number of lawyers working in the field of legal services respect to the population... [edited by author] XIII n.s.

2013 - 2014 This thesis deals empirically with various research questions in environmental economics. In particular the issues of sustainability and eco-efficiency are approached on three different data-sets. The first paper deals with the analysis of eco-efficiency for 103 provincial (NUTS 3 - Nomenclature of Units for Territorial Statistics 3) capitals of Italy throughout 2000-2008. It focuses on the link among economic growth, energy consumption and air pollution, modeling cities as territorial units that ought to promote growth, while at the same time minimising its environmental impact. Subsequently, the eco-efficiency of this panel of provincial capitals is measured through panel estimates of an input-distance function. Within this procedure, considering some environmental control variables, the paper evaluates if environmental best practices correspond either to those municipalities that adopt environment-friendly policies or to cities characterised by a particular urban context. The evidence points to the existence of a significant link between economic development, energy consumption and air pollution at the provincial capital level. The most ecoefficient provincial capitals are also among the wealthier, which is consistent with an Environmental Kuznets Curve. The second paper investigates the Ecological Footprint indicator by focusing on the notion of sustainable development and then of carrying capacity of land. The impact of man on nature is explored through an empirical analysis of the growth rate of population, and the percentage of urban and rural population, in Europe. The level of CO2 emissions per inhabitant in the EU is compared with that of developing countries. Through a sectoral approach, the total CO2 emissions per capita from fuel combustion, electricity and heat production, manufacturing industries and construction, transport and other sources are separately appraised. The third paper studies the relationship between rice production and methane emissions. Rice farming is believed to be a major anthropogenic source of methane emissions, which are measured emissions at both country and world levels of aggregation. It presents a quantitative estimation of the statistical relationship between rice production dynamics and methane emissions with regression estimates computed (country-wise and globally) over a large set of countries. The evidence only partly validates the expectation of a positive statistical influence of rice production on methane emissions. In fact a Kuznetstype evidence shows up: increasing rice production is correlated with fewer emissions. This negative relationship holds for a measure of countries sufficient to emerge significantly also at the world level. [edited by Author] XIII n.s.

2012 - 2013 This project includes three essays in Corporate Finance. The rst part of the thesis investigates the relationship between Financial Development and Economic Growth for a set of 77 countries over the period 1960-1995. Borrowing the methodology suggested by Beck, Levine and Loayza (2000), I study the previous relationship using a cross-country regression model and a panel technique. My results suggest that Private Credit, de ned as credits by nancial intermediaries to the private sector divided by GDP, has a positive impact over Economic Growth. My ndings also point out that Economic Growth is positively a¤ected by openness to trade and average years of schooling. The relationship between Financial Development and Economic Growth is independent of the degree of nancial development as well as the initial level of income of a given country. Di¤erently from other papers, I can study whether the nance-growth nexus is persistent over time: using a similar dataset for an extended period, 1960-2010, I show that the impact of Private Credit over Growth is signi cative also in the most recent past. The second part of the thesis explores the stock-prices comovements for a set of 7 countries over the period 2000-2014. The study explores how the volatilities and correlations in one coun- try, mainly Italy, are a¤ected by the volatilities and correlations in another country. Di¤erently from other papers, I focus on a larger set of countries and on a sample period that allows to distinguish between the Pre Great Recession period and the Post Great Recession period. The analysis is conducted by considering several GARCH models, for the volatility comovements, and MGARCH models, for the correlation comovements. The best GARCH model in my set- ting is the EGARCH model which provides information on the impact of positive innovations on volatility. Among the MGARCH models, I focus on the CCC model and the DCC model. My results point out that the strenght of the relationship among countries is ampli ed after a crisis event, which is consistent with most of the "contagion" literature. The last part of the thesis analyzes the relationship between long-term debt and average investment during the 2007 crisis. Very few papers have analyzed the real e¤ects of debt ma- turity. To analyze the impact of the debt structure on rms performance I use a matching approach methodology (Abadie-Imbens estimator) which allows to distinguish between a treat- ment group and a control group: the rst one refers to the group of rms whose long-term debt is maturing at the time of the crisis, while, on the other hand, the control group refers to those rms that are out of the treatment but have similar rm characteristics like cash ow, size, Q, cash holdings and long-term leverage. My results show that rms with debt maturing during the period of the crisis experience a much more pronounced fall in investment. Results are tested using a Parallel Trend Test which allows to better de ne whether the results are driven by the maturity argument or not. [edited by author] XII n.s.

2013 - 2014 Growth and labour market forecast in OECD countries remains bleak for 2013, especially for youth. The modest employment recovery in 2011 did not continue in 2012: youth unemployment rates stagnated at 15.7% in 2014 (OECD: Employment Outlook, 2013). This is well above pre-crisis rates, 11.8% in 2007. According to the OECD, the modest increase in GDP forecasted for 2013 (1.2%) and the subsequent slow recovery in 2014 (2.3%) will be insufficient to create employment and reduce unemployment in a substantial way.It is particularly alarming that one every 11 young people are now unemployed, not in full time studies or in employment. Also youth have lower access to unemployment benefits that adults, for lack of employment history (OECD, 2010, off to a Good Start, Jobs for Youth Synthesis Report). These trends have contributed to higher rates of poverty and social exclusion and increasing polarization in society and in the labour market. For instance, living standards decreased in 15 Member States in 2010 with respect to the year before (Eurostat, March 2013). These issues represent tremendous social and economic costs to society, in terms of worsening social dislocation, skills loss, violence and crime, as much as they denote important failures to get unemployed back to productive and sustainable jobs, and to protect youth at risk of poverty. Aggregate demand is low and this certainly explains high levels of youth unemployment rates. However a number of barriers may prevent that demand translate into higher employment for youth. In particular, vocational training might not be well adapted to changing labour market requirements. In addition, there could be demand-side obstacles to youth employment. Employers, for example, might be faced with high social security contributions for low-paid work, or face high minimum wages. There might be insufficient support to help the young unemployed to find work. Finally, jobs prospects for youth are hampered by limited regional mobility in some countries of Central and Eastern Europe and South Europe (OECD, Jobs for Youth, Synthesis Report, 2010). This thesis seeks to measure whether high levels of minimum wages could explain rising unemployment rates for youth in OECD countries, other things equal. It also looks at whether other labour market institutions, such as strict Employment Protection Legislation (EPL) can explain low employment levels (for youth). It takes into account also the role paid by active labour market policy, collective agreement and a youth sub-minimum wage for 2 youth. The analysis uses a cross-section of panel data on minimum wages over the period 2000 to 2011, while from 2000 to 2008 for others employment protection legislation, and from 2004 to 2011 for active labour market policies indictors, including 22 OECD. Following Bassanini and Duval(2010), a panel data model has been used including GMM indicator, using the same data base but including different time period. The main conclusions are that, minimum wage, measured with Kaitz Index, has a negative impact on youth employment. Additionally, some ALMP’S seem to show a positive effect on youth employment(elasticity); this is a very important thing mainly because it has never been estimated in previous paper(only the theory was able to support it). Considering labor market institutions, their impact depends by which one we consider: union density confirms its negative impact on youth employment rate, while on the other hand EPL variable using OECD definition confirms its positive effect on youth employment. ALMP’S have a great influence on youth employment rate, several variables are positive and significant, while other variable included in the model only in part confirms previous literature. The last part of the second chapter ends with a little discussion about gender discrimination in the issue of youth employment too. As results show, also if the sign of the variable is always the same (confirming both literature and the goodness of the model), however the magnitude tends to be stronger (in negative meaning), for female estimates... [edited by Author] XIII n.s.

2009 - 2010, Research aims to analyze the operating performance of companies in the water services sector in the various Italian regions, to locate the position, in terms of overall profitability, of the Acquedotto Lucano Spa, a public company owned by the municipalities of the Region of Basilicata, which manages the integrated water service. Research was based on a sample where the database was constructed from data collected with the help of CNEL and the Osservatorio dei Servizi Pubblici Locali. It was, then, identified a set of indicators of financial statements that give an account of the economic structure and financial position of the various companies that manage the SII on the national territory. Through the use of appropriate techniques of clustering, we determined the distances between the statistical units in our sample and identified, finally, the positioning of the Region of Basilicata compared to other companies in the sample, obtaining, therefore, homogeneous groupings of companies that exhibit similar levels of economic, financial and equity indicators. Since we did not have data on the effectiveness of a particular clustering methodology compared to the other, we have followed different approaches to cluster analysis, thereby being able to measure how much each category of algorithms was appropriate to the study of such samples of data. Hierarchical methods have provided only general indications, a signal that the sample data are extremely cohesive and compact. a feature that has made problematic even the application of density methods, as it also determines a little variation in density between the data. Using k-means algorithm, we obtained important information about the number of clusters in which to split the sample, however, the values of the performance indicators we were not convinced of the complete reliability of the cluster boundaries identified. In order to obtain a more precise profile of the individual regions of homogeneity we have used a genetic algorithm, suitably calibrated, which has provided the cluster with surfaces of complex shape and non-linear, allowing a better interpretation of the results... [edited by author], IX n.s.

2012-2013, Lo scopo della presente ricerca è stato quello di individuare le differenze relative alla propensione cooperativa ed a quella punitiva tra un campione di studenti, uno di camorristi ed uno di detenuti comuni. A tal fine sono stati realizzati due esperimenti, composti da due diversi disegni, rappresentati rispettivamente dal classico gioco del Dilemma del Prigioniero (PD) e da un Dilemma del Prigioniero con punizione di un terzo (TP-PD). I camorristi nel PD hanno manifestato una propensione cooperativa nettamente superiore a quella degli studenti ed a quella dei detenuti comuni, mentre nel TP-PD i due campioni di criminali hanno evidenziato un livello sostanzialmente identico di cooperazione, anche se rispetto alla minaccia di subire la sanzione hanno reagito in maniera opposta (i camorristi hanno ridotto il livello di cooperazione rispetto al PD mentre i comuni hanno fatto registrare un incremento). Gli studenti, al pari dei camorristi, nel TP-PD hanno cooperato meno rispetto a quanto abbiano deciso di fare nel Dilemma del Prigioniero. Inoltre, sia i camorristi che i detenuti comuni nel TP-PD hanno evidenziato una forte propensione punitiva (maggiore di quella rilevatasi negli studenti), anche se la rispettiva modalità di applicazione si è mostrata diversa. Inoltre ai tre campioni sono stati somministrati una serie di quesiti, contenuti in un apposito questionario, al fine di verificare le affinità/divergenze tra le decisioni concretamente assunte nel gioco e le risposte fornite alle domande formulate.[a cura dell'autore], XII ciclo n.s.

2011 - 2012, La tesi analizza gli effetti delle attività di manipolazione delle informazioni, realizzate dai manager delle società per azioni, sull'efficienza dell'impresa e del mercato. La prima parte della tesi presenta una sintesi della letteratura sulle attività di manipolazione. Si analizzano le questioni più importanti relative alla rilevanza empirica di queste attività e ai loro costi sociali, focalizzando l’attenzione sui problemi di asimmetria informativa che possono rendere tali attività profittevoli dal punto di vista dei manager e sui diversi meccanismi di governance in grado di controllarne l'estensione. Nel corso dell’analisi si evidenziano due principali strumenti di corporate governance: il contratto ottimo e i meccanismi di monitoring delle attività di manipolazione. Nella seconda parte della tesi si analizza, attraverso un classico modello principale-agente con azzardo morale e multitasking, da un lato la relazione tra le variabili che definiscono le "opportunità di manipolazione" e gli incentivi delle imprese a controllare l'estensione della manipolazione attraverso il contratto ottimo, dall'altro l'effetto che le variazioni normative volte a rafforzare l'efficacia degli strumenti di controllo dell'attività di manipolazione (cosiddetta corporate governance esterna) hanno sull'utilizzo degli incentivi contrattuali. Più specificamente, analizziamo la relazione tra variazione delle opportunità di manipolazione e potere degli incentivi contrattuali in assenza di sistemi di monitoring dell'attività manipolatoria, e dimostriamo che esistono equilibri dove una elevata intensità degli incentivi di second best è compatibile con alti livelli di manipolazione. Si dimostra inoltre che le perdite di second best generate dalle asimmetrie informative (che nel nostro modello sono inversamente proporzionali ai profitti delle imprese) non sono in generale una funzione crescente delle opportunità di manipolazione e che, quando la governance interna all'impresa genera opportunità di manipolazione elevate per il manager, variazioni del sistema di governance relativamente "piccole", che accrescono i costi di manipolare per il manager, si traducono in perdite di profitto per l'impresa stessa. Infine studiamo gli effetti di un miglioramento dell'efficienza del sistema di monitoring della manipolazione (che nel modello si assume esterno all'impresa) sul potere degli incentivi contrattuali offerti dall'impresa e sulle perdite di second best generate dalle asimmetrie informative. Dimostriamo in particolare che quando le opportunità di manipolazione sono elevate, gli incentivi monetari crescono ed i profitti delle imprese diminuiscono al crescere della penalità attesa associata alla scoperta della manipolazione, mentre avviene il contrario quando le opportunità di manipolazione sono meno elevate. Questi risultati indicano l'esistenza di una relazione di segno non monotono tra l'efficienza del sistema di monitoring e il surplus generato dalla relazione tra principale e agente. Infine, i risultati di statica comparata rispetto al grado di efficienza del sistema di governance interno e quelli che analizzano gli effetti di variazioni di efficienza del sistema di governance esterno dimostrano che in generale, miglioramenti di efficienza della governance esterna (rispettivamente interna) aumentano il surplus della relazione tra impresa e manager solo per livelli sufficientemente elevati della governance interna (rispettivamente esterna). [a cura dell'autore], XI n.s.

2008 - 2009 In the last twenty years the banking sector of many countries has undergone a period of consolidation and restructuring. This has raised concerns about the welfare implications of larger credit institutions, given that the banking industry is vital for the whole economic system. From a theoretical point of view, one should expect two "direct" effects from these structural transformations. First of all, consolidation may allow banks to achieve a higher level of efficiency thanks to the exploitation of scale and scope economies. Secondly, mergers and acquisitions among credit institutions could lead to an increase in local market concentration and thus, as maintained by the Structure-Conduct Performance (SCP) paradigm, to an increase in banks' market power. In turn, market power in banking is the channel through which the consolidation process could have some "indirect effects" on other economic phenomena. Indeed, as shown by recent empirical works, the degree of competition in banking markets is a key explanatory variable of banks' X-efficiency, as well as credit availability for small firms, relationship banking, economic growth and financial stability. In this dissertation we empirically explore some of the consequences of the consolidation process, focusing on the italian banking industry. More precisely, Chapter One studies the effect on banks' cost efficiency. Starting from a Multi-output Symmetric Generalized McFadden cost function, we estimate a system of factor demand equations in order to assess the degree of scale and scope economies of Italian banks in the period 1992-2007. We find evidence of slight economies of scale and significant economies of scope. Our main conclusion is that the efficiency gains coming from merger and acquisition operations could be an explanation of the consolidation process; at the same time, they could translate into beneficial effects for consumers and firms, provided that they are not offset by an increased market power… [a cura dell’Autore] VIII n.s.

2007 - 2008 Since the end of the Cold War, the incidence of civil war has decreased and the use of peacekeeping has increased. This thesis examines some of the factors that influence the demand for peacekeeping missions, in particular the forces prompting civil war, and the supply of peacekeeping, the ability and desire of nations to intervene through peacekeeping missions. Given the considerable ambiguities associated with peacekeeping, we attempt to integrate third party intervention into traditional bilateral models of conflict and investigate the extent to which conflict models can help the intervening nation develop more effective strategies. Determining the objectives of the intervening governments is crucial. The second part of this thesis addresses the motivations that interact to produce troop contribution by a diverse pool of participants. Results suggest that at the domestic level the comparative advantage in manpower, the tolerance of casualties and the sustainability of multiple missions, all play a role. At the international level peacekeeping contributions are driven by the global security threat, the proximity to the conflict area and the number of displaced people. A number of NATO members have suspended compulsory military services, moving to an All-Volunteer Force. Since ending conscription tends to have two opposite effects, fewer soldiers paid higher wages, it is not obvious what the net effect on personnel cost is. We show that while the end of conscription did not reduce the share of spending on personnel, NATO forces are increasingly less reliant on soldiers and more on capital. The final part of the thesis returns to the demand side. Security incidents in Afghanistan have been rising since 2003. Given the links between anti-government elements in the country and its drug economy, we investigate the interaction between opium prices, alternative measures of income, and insurgency activities in the Afghan provinces. We find that unobservable common channels prevail in determining how income and conflict dynamics interact. [edited by author] VII n.s.

2008 - 2009 La tesi analizza gli e¤etti dell incompletezza contrattuale sull e¢ cienza di una relazione d agenzia caratterizzata da selezione avversa ed azzardo morale quando l agente opera in un mercato (imperfettamente) concorrenziale. La prima parte della ricerca o¤re una breve panoramica della letteratura esistente in materia di contratti incompleti al ne di mostrare le di¤erenti prospettive di analisi che si sono alternate nel corso degli anni. Sebbene inizialmente l incompletezza fosse vista come un elemento negativo, che limita in maniera determinante l e¢ cienza delle transazioni economiche, approcci più recenti hanno evidenziato altri e¤etti derivanti dal ricorso a contratti non contingenti, riconoscendo la valenza strategica di tale caratteristica. La seconda parte della tesi utilizza gli strumenti classici della teoria degli incentivi per isolare le condizioni in presenza delle quali il ricorso ad un contratto incompleto garantisce un miglioramento dell e¢ cienza della transazione. In particolare, i due modelli considerati dimostrano che la rinuncia ad uno o più strumenti di controllo del proprio partner permette al principale di limitare gli e¤etti negativi derivanti dalla distribuzione asimmetrica dell informazione e di ottenere un miglior pro tto atteso, grazie al corretto sfruttamento del gioco concorrenziale che si sviluppa sul mercato a valle. [a cura dell'autore] VIII n.s.

2007 - 2008 The aim of this thesis is to contribute to the debate on the Beveridge Curve: more specifically, after providing a theoretical introduction to the Curve in Chapter I, we focus on some empirical points, concerning globalisation and technological progress, which the international empirical literature has not dealt with closely (Chapter II), and on a level analysis which no previous study has dealt with in the Italian literature (Chapter III). Chapter I centres on the matching approach founding the studies on the Beveridge Curve since the late 1970's, it also mentions the recent production frontier approach and gives a look to the possible consequences of the Great Recession on the matching process and the Curve. The aim of Chapter II is to test the existence of a Beveridge Curve analysing the economies of nineteen OECD countries from 1980 to 2004, and to investigate whether and how technological progress and globalisation affect the unemployment-vacancies trade-off. Indeed, in the literature concerning the Beveridge Curve, only a few contributions (Pissarides, 1990; Aghion and Howitt, 1994) have examined the role of technological progress as a significant shift factor for labour market performance. However, there is no unanimity about the sign of its impact. Furthermore, few economists would deny that globalisation, that is the growing international interdependence in communications, trade, finance, labour markets (migration), social systems, is one of fundamental socio-economic phenomena of this turn of century. Consequently, globalisation is another factor which is expected to impact on the Beveridge Curve, but no full-fledged estimation has, to the best of our knowledge, ever been carried out of this nexus. We can sum up the main results as follows: a) we find largely favourable evidence for the existence of a OECD Beveridge Curve; b) lagged values of technological progress impact positively on unemployment and shift the Beveridge Curve outwards, producing evidence in support of the creative destruction effect; c) lagged values of the globalisation index have a positive impact on unemployment, also shifting the Beveridge Curve outwards; d) a critical econometric issue, extremely neglected by the previous literature, is represented by endogeneity, as shown by tests and other kind of evidence. Finally, Chapter III focuses on the Italian labour market. There are not many studies that have analyzed the Beveridge Curve in Italy, likely because of the lack of official data on vacancies. Moreover, no previous study has focused specifically on a regional level analysis of the Beveridge Curve. Chapter III aims at filling this gap of the literature using quarterly data for the 1992-2009 period. In particular, the ISAE labour scarcity indicator, which is available for all the regions, is used to build regional vacancy rates. Like in Destefanis and Fonseca (2007), we also investigate the impact on matching efficiency of the recent strong development in the number of so-called atypical jobs (both part-time and temporary)… [edited by author]. VII n.s.

2007 - 2008 La tesi, dopo aver premesso la condizione di crisi in cui versa la giustizia italiana, propone una definizione di sistema giudiziario. Emergono tre principali dimensioni interessanti per ogni analisi, sia del sistema nel suo complesso, sia dei singoli aspetti. Viene proposta, inizialmente, una rassegna dei confronti internazionali tra sistemi giudiziari di diversi paesi. Seguono gli studi che si concentrano, esclusivamente, su di un singolo sistema giudiziario nazionale. A questo punto viene proposta un’analisi empirica del sistema giudiziario italiano. Dopo avere illustrato le particolarità del sistema italiano, si procede, mediante la Data Envelopment Analysis (DEA), alla misurazione dell'efficienza tecnica e di scala di corti d'appello e tribunali ordinari. Un primo obiettivo di questo studio è stato quello di sopperire alla carenza nella letteratura di uno studio relativo ai singoli uffici giudiziari italiani del primo e del secondo grado di giudizio. Oltre ad una disaggregazione più fine, l’analisi presenta, anche, una maggiore estensione temporale delle osservazioni. La scelta, anch’essa innovativa, di distinguere gli output in base a tre differenti tipologie di procedimenti giudiziari (penali, in materia di lavoro e previdenza e altri procedimenti civili), ha consentito di migliorare la significatività dei risultati. Emerge dalla DEA che le efficienze tecniche delle corti di appello, soprattutto, e dei tribunali, non sono molto differenziate geograficamente. Peraltro, vi è stato in tutti gli uffici giudiziari un significativo aumento dell'efficienza tecnica. Non vi è aumento invece per le efficienze di scala, che tuttavia risultano abbastanza elevate. Primo e secondo grado di giudizio vengono considerati congiuntamente, in un secondo step dell'analisi (a nostra conoscenza, mai prima considerato in letteratura) nel quale le misure di efficienza, insieme ad altre variabili, vengono messe in relazione, mediante opportune tecniche di regressione, con la durata media dei procedimenti. Inoltre, viene esaminata la significatività di alcune variabili per la determinazione dell’efficienza. Emerge chiaramente che la durata dei procedimenti dipende dalla litigiosità (ritardata di un anno), ma è ridotta da un aumento nella dotazione di input, o dell'efficienza tecnica. Conta poco anche qui l'efficienza di scala. Per le corti d'appello sono i magistrati a essere l'input più significativo, mentre questo ruolo è assunto dagli amministrativi per i tribunali ordinari. Non è infine possibile trovare alcuna variabile significativa per la determinazione dell'efficienza tecnica (compresa, per le corti d'appello, l'efficienza media dei tribunali del distretto), se si tiene conto del ruolo degli effetti individuali dati. [a cura dell'autore] VII n.s.