999 resultados para Politica monetaria - Modelli econometrici


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In martial arts there are several ways to perform the turning kick . Following the martial arts or different learning models many types of kicks take shape. Mawashi geri is the karate turning kick. At the moment there are two models of mawashi geri, one comes from the traditional karate (OLD), and the other newer (NEW), who agrees to the change of the rules of W.K.F. (World Karate Federation) happened in 2000 (Macan J. et all 2006) . In this study we are focus on the differences about two models the mawashi geri jodan of karate. The purpose of this study is to analyse cinematic and kinetic parameters of mawashi geri jodan. Timing of the striking and supporting leg actions were also evaluated A Vicon system 460 IR with 6 cameras at sample frequency of 200 Hz was used. 37 reflective markers have been set on the skin of the subjects following the “PlugInGait-total body model”. The participants performed five repetitions of mawashi geri jodan at maximum rapidity with their dominant leg against a ball suspended in front of them placed at ear height. Fourteen skilled subjects (mean level black belt 1,7 dan; age 20,9±4,8 yrs; height 171,4±7,3 cm; weight 60,9±10,2 Kg) practicing karate have been split in two group through the hierarchical cluster analysis following their technical characteristics. By means of the Mann Whitney-U test (Spss-package) the differences between the two groups were verified in preparatory and execution phase. Kicking knee at start, kicking hip and knee at take-off were different between the two groups (p < 0,05). Striking hip flexion during the spin of the supporting foot was different between the two groups (p < 0,05). Peak angular velocity of hip flexion were different between the two groups (p < 0,05). Groups showed differences also in timing of the supporting spin movement. While Old group spin the supporting foot at 30% of the trial, instead New start spinning at 44% of the trial. Old group showed a greater supporting foot spin than New (Old 110° Vs New 82°). Abduction values didn’t show any differences between the two groups. At the hit has been evaluated a 120° of double hips abduction, for the entire sample. Striking knee extension happened for everybody after the kicking hip flexion and confirm the proximal-distal action of the striking leg (Sorensen H. 1996). In contrast with Pearson J.N. 1997 and Landeo R 2007, peak velocity of the striking foot is not useful to describe kick performance because affected by the stature. Two groups are different either in preparatory phase or in execution phase. The body is set in difference manner already before the take-off of the kicking foot. The groups differ for the timing of the supporting foot action Trainer should pay attention to starting posture and on abduction capacities of the athletes.

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In questa Tesi vengono trattati alcuni temi relativi alla modellizzazione matematica delle Transizioni di Fase, il cui filo conduttore è la descrizione basata su un parametro d'ordine, originato dalla Teoria di Landau. Dopo aver presentato in maniera generale un modo di approccio alla dinamica delle transizioni mediante campo di fase, con particolare attenzione al problema della consistenza termodinamica nelle situazioni non isoterme, si considerano tre applicazioni di tale metodo a transizioni di fase specifiche: la transizione ferromagnetica, la transizione superconduttrice e la transizione martensitica nelle leghe a memoria di forma (SMA). Il contributo maggiore viene fornito nello studio di quest'ultima transizione di fase per la quale si è elaborato un modello a campo di fase termodinamicamente consistente, atto a descriverne le proprietà termomeccaniche essenziali.

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Il lavoro presentato si propone di fornire un contributo all'implementazione di indagini finalizzate a misurare l'evoluzione delle intenzioni d'acquisto del consumatore italiano nei confronti degli OGM, data anche l'impossibilità  al momento di avere indicazioni e dati sul comportamento (vista la quasi totale assenza dei prodotti OGM nella distribuzione, se si eccettuano i prodotti d'allevamento di animali alimentati con OGM per cui non è previsto nessun obbligo di etichettatura). Le coltivazioni transgeniche (Organismi Geneticamente Modificati) si stanno diffondendo abbastanza rapidamente nel contesto mondiale, dal 1996, primo anno in cui sono uscite dalla fase sperimentale, ad oggi. Nel 2008 la superficie globale delle colture biotech è stata di 125 milioni di ettari, circa il 9% in più rispetto ai 114 milioni del 2007, mentre il numero dei Paesi che hanno adottato varietà  GM è giunto a 25. Di questi sono soprattutto Usa, Canada, Argentina, Brasile, Cina e India a trainare la crescita; le colture più diffuse sono soia, mais, cotone e colza, prodotti destinati principalmente al segmento feed e al segmento no-food e solo in minima parte al segmento food (cioè all'alimentazione diretta umana). Molte più resistenze ha incontrato tale sviluppo nei Paesi dell'Unione europea. A tutt'oggi le coltivazioni GM hanno raggiunto estensioni significative solamente in Spagna, con alcune decine di migliaia di ettari di mais GM. Mais che peraltro è l'unica produzione per cui è stata autorizzata una varietà  GM alla coltivazione. Si intuisce in sostanza come in Europa si sia assunto un atteggiamento molto più prudente verso l'utilizzo su larga scala di tale innovazione scientifica, rispetto a quanto accaduto nei grandi Paesi citati in precedenza. Una prudenza dettata dal serrato dibattito, tuttora in corso, tra possibilisti e contrari, con contrapposizioni anche radicali, al limite dell'ideologia. D'altro canto, le indagini di Eurobarometro hanno messo in luce un miglioramento negli ultimi anni nella percezione dei cittadini europei verso le biotecnologie: dopo aver raggiunto un livello minimo di fiducia nel 1999, si è manifestata una lenta risalita verso i livelli di inizio anni '90, con percentuali di "fiduciosi" intorno al 55-60% sul totale della popolazione. Tuttavia, sebbene sulle biotecnologie in genere (l'Eurobarometro individua quattro filoni: alimenti contenenti OGM, terapie geniche, nanotecnologie e farmaci contenenti OGM), il giudizio sia abbastanza positivo, sugli alimenti permane un certo scetticismo legato soprattutto a considerazioni di inutilità  della tecnologia, di rischio percepito e di accettabilità morale: per citare il caso italiano, che, contrariamente a quello che si potrebbe pensare, è tra i più elevati nel contesto europeo, solamente un cittadino su tre valuta positivamente gli alimenti contenenti OGM. Se si analizza, inoltre, il sentiment del settore agricolo, nel quale il tema riveste anche un'importanza di natura economico-produttiva, in quanto incidente sui comportamenti e sulla strategie aziendali, sembra emergere un'apertura significativamente più elevata, se non una vera e propria frattura rispetto all'opinione pubblica. Infatti, circa due maiscoltori lombardi su tre (Demoskopea, 2008), cioè la tipologia di agricoltori che potrebbe beneficiare di tale innovazione, coltiverebbero mais GM se la normativa lo consentisse. Ebbene, in tale contesto diventa d'estremo interesse, sebbene di non facile praticabilità , lo studio e l'implementazione di modelli volti a monitorare le componenti che concorrono a formare l'intenzione e, in ultima analisi, il comportamento, dei consumatori verso gli OGM. Un esercizio da attuare per lo più tramite una serie di misurazioni indirette che devono fermarsi necessariamente all'intenzione nel caso italiano, mentre in altri Paesi che hanno avuto legislazioni più favorevoli all'introduzione degli OGM stessi nella produzione food può perseguire approcci d'analisi field, focalizzati non solo sull'intenzione, ma anche sul legame tra intenzione ed effettivo comportamento. Esiste una vasta letteratura che studia l'intenzione del consumatore verso l'acquisto di determinati beni. Uno degli approcci teorici che negli ultimi anni ha avuto più seguito è stato quello della Teoria del Comportamento Pianificato (Ajzen, 1991). Tale teoria prevede che l'atteggiamento (cioè l'insieme delle convinzioni, credenze, opinioni del soggetto), la norma soggettiva (cioè l'influenza dell'opinione delle persone importanti per l'individuo) e il controllo comportamentale percepito (ovvero la capacità , auto-percepita dal soggetto, di riuscire a compiere un determinato comportamento, in presenza di un'intenzione di ugual segno) siano variabili sufficienti a spiegare l'intenzione del consumatore. Tuttavia, vari ricercatori hanno e stanno cercando di verificare la correlazione di altre variabili: per esempio la norma morale, l'esperienza, l'attitudine al rischio, le caratteristiche socio-demografiche, la cosiddetta self-identity, la conoscenza razionale, la fiducia nelle fonti d'informazione e via discorrendo. In tale lavoro si è cercato, quindi, di esplorare, in un'indagine "pilota" quali-quantitativa su un campione ragionato e non probabilistico, l'influenza sull'intenzione d'acquisto di prodotti alimentari contenenti OGM delle variabili tipiche della Teoria del Comportamento Pianificato e di alcune altre variabili, che, nel caso degli OGM, appaiono particolarmente rilevanti, cioè conoscenza, fiducia nelle fonti d'informazione ed elementi socio-demografici. Tra i principali risultati da porre come indicazioni di lavoro per successive analisi su campioni rappresentativi sono emersi: - La conoscenza, soprattutto se tecnica, sembra un fattore, relativamente al campione ragionato analizzato, che conduce ad una maggiore accettazione degli OGM; le stesse statistiche descrittive mettono in luce una netta differenza in termini di intenzione d'acquisto dei prodotti contenenti OGM da parte del sub-campione più preparato sull'argomento; - L'esplorazione della fiducia nelle fonti d'informazione è sicuramente da approfondire ulteriormente. Dall'indagine effettuata risulta come l'unica fonte che influenza con le sue informazioni la decisione d'acquisto sugli OGM è la filiera agroalimentare. Dato che tali attori si caratterizzano per lo più con indicazioni contrarie all'introduzione degli OGM nei loro processi produttivi, è chiaro che se il consumatore dichiara di avere fiducia in loro, sarà  anche portato a non acquistare gli OGM; - Per quanto riguarda le variabili della Teoria del Comportamento Pianificato, l'atteggiamento mette in luce una netta preponderanza nella spiegazione dell'intenzione rispetto alla norma soggettiva e al controllo comportamentale percepito. Al contrario, queste ultime appaiono variabili deboli, forse perchè a tutt'oggi la possibilità  concreta di acquistare OGM è praticamente ridotta a zero ; - Tra le variabili socio-demografiche, l'influenza positiva del titolo di studio sulla decisione d'acquisto sembra confermare almeno in parte quanto emerso rispetto alla variabile "conoscenza"; - Infine, il fatto che il livello di reddito non influisca sull'intenzione d'acquisto appare abbastanza scontato, se si pensa, ancora una volta, come a tutt'oggi gli OGM non siano presenti sugli scaffali. Il consumatore non ha al momento nessuna idea sul loro prezzo. Decisamente interessante sarà  indagare l'incidenza di tale variabile quando il "fattore OGM" sarà  prezzato, presumibilmente al ribasso rispetto ai prodotti non OGM.

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The aim of this PhD thesis is to study accurately and in depth the figure and the literary production of the intellectual Jacopo Aconcio. This minor author of the 16th century has long been considered a sort of “enigmatic character”, a profile which results from the work of those who, for many centuries, have left his writing to its fate: a story of constant re-readings and equally incessant oversights. This is why it is necessary to re-read Aconcio’s production in its entirety and to devote to it a monographic study. Previous scholars’ interpretations will obviously be considered, but at the same time an effort will be made to go beyond them through the analysis of both published and manuscript sources, in the attempt to attain a deeper understanding of the figure of this man, who was a Christian, a military and hydraulic engineer and a political philosopher,. The title of the thesis was chosen to emphasise how, throughout the three years of the doctorate, my research concentrated in equal measure and with the same degree of importance on all the reflections and activities of Jacopo Aconcio. My object, in fact, was to establish how and to what extent the methodological thinking of the intellectual found application in, and at the same time guided, his theoretical and practical production. I did not mention in the title the author’s religious thinking, which has always been considered by everyone the most original and interesting element of his production, because religion, from the Reformation onwards, was primarily a political question and thus it was treated by almost all the authors involved in the Protestant movement - Aconcio in the first place. Even the remarks concerning the private, intimate sphere of faith have therefore been analysed in this light: only by acknowledging the centrality of the “problem of politics” in Aconcio’s theories, in fact, is it possible to interpret them correctly. This approach proves the truth of the theoretical premise to my research, that is to say the unity and orderliness of the author’s thought: in every field of knowledge, Aconcio applies the rules of the methodus resolutiva, as a means to achieve knowledge and elaborate models of pacific cohabitation in society. Aconcio’s continuous references to method can make his writing pedant and rather complex, but at the same time they allow for a consistent and valid analysis of different disciplines. I have not considered the fact that most of his reflections appear to our eyes as strongly conditioned by the time in which he lived as a limit. To see in him, as some have done, the forerunner of Descartes’ methodological discourse or, conversely, to judge his religious theories as not very modern, is to force the thought of an author who was first and foremost a Christian man of his own time. Aconcio repeats this himself several times in his writings: he wants to provide individuals with the necessary tools to reach a full-fledged scientific knowledge in the various fields, and also to enable them to seek truth incessantly in the religious domain, which is the duty of every human being. The will to find rules, instruments, effective solutions characterizes the whole of the author’s corpus: Aconcio feels he must look for truth in all the arts, aware as he is that anything can become science as long as it is analysed with method. Nevertheless, he remains a man of his own time, a Christian convinced of the existence of God, creator and governor of the world, to whom people must account for their own actions. To neglect this fact in order to construct a “character”, a generic forerunner, but not participant, of whatever philosophical current, is a dangerous and sidetracking operation. In this study, I have highlighted how Aconcio’s arguments only reveal their full meaning when read in the context in which they were born, without depriving them of their originality but also without charging them with meanings they do not possess. Through a historical-doctrinal approach, I have tried to analyse the complex web of theories and events which constitute the substratum of Aconcio’s reflection, in order to trace the correct relations between texts and contexts. The thesis is therefore organised in six chapters, dedicated respectively to Aconcio’s biography, to the methodological question, to the author’s engineering activity, to his historical knowledge and to his religious thinking, followed by a last section concerning his fortune throughout the centuries. The above-mentioned complexity is determined by the special historical moment in which the author lived. On the one hand, thanks to the new union between science and technique, the 16th century produces discoveries and inventions which make available a previously unthinkable number of notions and lead to a “revolution” in the way of studying and teaching the different subjects, which, by producing a new form of intellectual, involved in politics but also aware of scientific-technological issues, will contribute to the subsequent birth of modern science. On the other, the 16th century is ravaged by religious conflicts, which shatter the unity of the Christian world and generate theological-political disputes which will inform the history of European states for many decades. My aim is to show how Aconcio’s multifarious activity is the conscious fruit of this historical and religious situation, as well as the attempt of an answer to the request of a new kind of engagement on the intellectual’s behalf. Plunged in the discussions around methodus, employed in the most important European courts, involved in the abrupt acceleration of technical-scientific activities, and especially concerned by the radical religious reformation brought on by the Protestant movement, Jacopo Aconcio reflects this complex conjunction in his writings, without lacking in order and consistency, differently from what many scholars assume. The object of this work, therefore, is to highlight the unity of the author’s thought, in which science, technique, faith and politics are woven into a combination which, although it may appear illogical and confused, is actually tidy and methodical, and therefore in agreement with Aconcio’s own intentions and with the specific characters of European culture in the Renaissance. This theory is confirmed by the reading of the Ars muniendorum oppidorum, Aconcio’s only work which had been up till now unavailable. I am persuaded that only a methodical reading of Aconcio’s works, without forgetting nor glorifying any single one, respects the author’s will. From De methodo (1558) onwards, all his writings are summae, guides for the reader who wishes to approach the study of the various disciplines. Undoubtedly, Satan’s Stratagems (1565) is something more, not only because of its length, but because it deals with the author’s main interest: the celebration of doubt and debate as bases on which to build religious tolerance, which is the best method for pacific cohabitation in society. This, however, does not justify the total centrality which the Stratagems have enjoyed for centuries, at the expense of a proper understanding of the author’s will to offer examples of methodological rigour in all sciences. Maybe it is precisely because of the reforming power of Aconcio’s thought that, albeit often forgotten throughout the centuries, he has never ceased to reappear and continues to draw attention, both as a man and as an author. His ideas never stop stimulating the reader’s curiosity and this may ultimately be the best demonstration of their worth, independently from the historical moment in which they come back to the surface.

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The Ph.D. dissertation analyses the reasons for which political actors (governments, legislatures and political parties) decide consciously to give away a source of power by increasing the political significance of the courts. It focuses on a single case of particular significance: the passage of the Constitutional Reform Act 2005 in the United Kingdom. This Act has deeply changed the governance and the organization of the English judicial system, has provided a much clearer separation of powers and a stronger independence of the judiciary from the executive and the legislative. What’s more, this strengthening of the judicial independence has been decided in a period in which the political role of the English judges was evidently increasing. I argue that the reform can be interpreted as a «paradigm shift» (Hall 1993), that has changed the way in which the judicial power is considered. The most diffused conceptions in the sub-system of the English judicial policies are shifted, and a new paradigm has become dominant. The new paradigm includes: (i) stronger separation of powers, (ii) collective (as well as individual) conception of the independence of the judiciary, (iii) reduction of the political accountability of the judges, (iv) formalization of the guarantees of judicial independence, (v) principle-driven (instead of pragmatic) approach to the reforms, and (vi) transformation of a non-codified constitution in a codified one. Judicialization through political decisions represent an important, but not fully explored, field of research. The literature, in particular, has focused on factors unable to explain the English case: the competitiveness of the party system (Ramseyer 1994), the political uncertainty at the time of constitutional design (Ginsburg 2003), the cultural divisions within the polity (Hirschl 2004), federal institutions and division of powers (Shapiro 2002). All these contributes link the decision to enhance the political relevance of the judges to some kind of diffusion of political power. In the contemporary England, characterized by a relative high concentration of power in the government, the reasons for such a reform should be located elsewhere. I argue that the Constitutional Reform Act 2005 can be interpreted as a result of three different kinds of reasons: (i) the social and demographical transformations of the English judiciary, which have made inefficient most of the precedent mechanism of governance, (ii) the role played by the judges in the policy process and (iii) the cognitive and normative influences originated from the European context, as a consequence of the membership of the United Kingdom to the European Union and the Council of Europe. My thesis is that only a full analysis of all these three aspects can explain the decision to reform the judicial system and the content of the Constitutional Reform Act 2005. Only the cultural influences come from the European legal complex, above all, can explain the paradigm shift previously described.

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The wheel - rail contact analysis plays a fundamental role in the multibody modeling of railway vehicles. A good contact model must provide an accurate description of the global contact phenomena (contact forces and torques, number and position of the contact points) and of the local contact phenomena (position and shape of the contact patch, stresses and displacements). The model has also to assure high numerical efficiency (in order to be implemented directly online within multibody models) and a good compatibility with commercial multibody software (Simpack Rail, Adams Rail). The wheel - rail contact problem has been discussed by several authors and many models can be found in the literature. The contact models can be subdivided into two different categories: the global models and the local (or differential) models. Currently, as regards the global models, the main approaches to the problem are the so - called rigid contact formulation and the semi – elastic contact description. The rigid approach considers the wheel and the rail as rigid bodies. The contact is imposed by means of constraint equations and the contact points are detected during the dynamic simulation by solving the nonlinear algebraic differential equations associated to the constrained multibody system. Indentation between the bodies is not permitted and the normal contact forces are calculated through the Lagrange multipliers. Finally the Hertz’s and the Kalker’s theories allow to evaluate the shape of the contact patch and the tangential forces respectively. Also the semi - elastic approach considers the wheel and the rail as rigid bodies. However in this case no kinematic constraints are imposed and the indentation between the bodies is permitted. The contact points are detected by means of approximated procedures (based on look - up tables and simplifying hypotheses on the problem geometry). The normal contact forces are calculated as a function of the indentation while, as in the rigid approach, the Hertz’s and the Kalker’s theories allow to evaluate the shape of the contact patch and the tangential forces. Both the described multibody approaches are computationally very efficient but their generality and accuracy turn out to be often insufficient because the physical hypotheses behind these theories are too restrictive and, in many circumstances, unverified. In order to obtain a complete description of the contact phenomena, local (or differential) contact models are needed. In other words wheel and rail have to be considered elastic bodies governed by the Navier’s equations and the contact has to be described by suitable analytical contact conditions. The contact between elastic bodies has been widely studied in literature both in the general case and in the rolling case. Many procedures based on variational inequalities, FEM techniques and convex optimization have been developed. This kind of approach assures high generality and accuracy but still needs very large computational costs and memory consumption. Due to the high computational load and memory consumption, referring to the current state of the art, the integration between multibody and differential modeling is almost absent in literature especially in the railway field. However this integration is very important because only the differential modeling allows an accurate analysis of the contact problem (in terms of contact forces and torques, position and shape of the contact patch, stresses and displacements) while the multibody modeling is the standard in the study of the railway dynamics. In this thesis some innovative wheel – rail contact models developed during the Ph. D. activity will be described. Concerning the global models, two new models belonging to the semi – elastic approach will be presented; the models satisfy the following specifics: 1) the models have to be 3D and to consider all the six relative degrees of freedom between wheel and rail 2) the models have to consider generic railway tracks and generic wheel and rail profiles 3) the models have to assure a general and accurate handling of the multiple contact without simplifying hypotheses on the problem geometry; in particular the models have to evaluate the number and the position of the contact points and, for each point, the contact forces and torques 4) the models have to be implementable directly online within the multibody models without look - up tables 5) the models have to assure computation times comparable with those of commercial multibody software (Simpack Rail, Adams Rail) and compatible with RT and HIL applications 6) the models have to be compatible with commercial multibody software (Simpack Rail, Adams Rail). The most innovative aspect of the new global contact models regards the detection of the contact points. In particular both the models aim to reduce the algebraic problem dimension by means of suitable analytical techniques. This kind of reduction allows to obtain an high numerical efficiency that makes possible the online implementation of the new procedure and the achievement of performance comparable with those of commercial multibody software. At the same time the analytical approach assures high accuracy and generality. Concerning the local (or differential) contact models, one new model satisfying the following specifics will be presented: 1) the model has to be 3D and to consider all the six relative degrees of freedom between wheel and rail 2) the model has to consider generic railway tracks and generic wheel and rail profiles 3) the model has to assure a general and accurate handling of the multiple contact without simplifying hypotheses on the problem geometry; in particular the model has to able to calculate both the global contact variables (contact forces and torques) and the local contact variables (position and shape of the contact patch, stresses and displacements) 4) the model has to be implementable directly online within the multibody models 5) the model has to assure high numerical efficiency and a reduced memory consumption in order to achieve a good integration between multibody and differential modeling (the base for the local contact models) 6) the model has to be compatible with commercial multibody software (Simpack Rail, Adams Rail). In this case the most innovative aspects of the new local contact model regard the contact modeling (by means of suitable analytical conditions) and the implementation of the numerical algorithms needed to solve the discrete problem arising from the discretization of the original continuum problem. Moreover, during the development of the local model, the achievement of a good compromise between accuracy and efficiency turned out to be very important to obtain a good integration between multibody and differential modeling. At this point the contact models has been inserted within a 3D multibody model of a railway vehicle to obtain a complete model of the wagon. The railway vehicle chosen as benchmark is the Manchester Wagon the physical and geometrical characteristics of which are easily available in the literature. The model of the whole railway vehicle (multibody model and contact model) has been implemented in the Matlab/Simulink environment. The multibody model has been implemented in SimMechanics, a Matlab toolbox specifically designed for multibody dynamics, while, as regards the contact models, the CS – functions have been used; this particular Matlab architecture allows to efficiently connect the Matlab/Simulink and the C/C++ environment. The 3D multibody model of the same vehicle (this time equipped with a standard contact model based on the semi - elastic approach) has been then implemented also in Simpack Rail, a commercial multibody software for railway vehicles widely tested and validated. Finally numerical simulations of the vehicle dynamics have been carried out on many different railway tracks with the aim of evaluating the performances of the whole model. The comparison between the results obtained by the Matlab/ Simulink model and those obtained by the Simpack Rail model has allowed an accurate and reliable validation of the new contact models. In conclusion to this brief introduction to my Ph. D. thesis, we would like to thank Trenitalia and the Regione Toscana for the support provided during all the Ph. D. activity. Moreover we would also like to thank the INTEC GmbH, the society the develops the software Simpack Rail, with which we are currently working together to develop innovative toolboxes specifically designed for the wheel rail contact analysis.

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La tesi si pone due obiettivi principali. Il primo é quello di proporre una rassegna ragionata della letteratura di carattere economico sulla Responsabilitá Sociale d’Impresa (RSI), analizzando i maggiori elementi di possibile critica e i nodi rimasti irrisolti. Il secondo é quello di introdurre alcuni contributi originali a questa letteratura. Riguardo al secondo obiettivo, l’analisi economica della RSI si puó dividere in due rami: uno che vede la RSI principamente come strategia di differenziazione, e l’altro che la vede come strategia per migliorare l’efficienza del processo produttivo. Fino ad ora la letteratura economica si é concentrata esclusivamente sul primo. Nella mia tesi vengono sviluppati alcuni modelli teorici delle RSI come strategia per migliorare l'efficienza del processo produttivo. Uno dei principali risultati della tesi é che le imprese che appaiono socialmente responsabili non sono quelle che hanno rinunciato alla massimizazione dei profitti, ma quelle che hanno come obiettivo la massimizzazione dei profitti nel lungo periodo, tenendo in considerazione come le proprie attivitá possono influenzare la disponibilitá e la qualitá dei fattori di produzione nel futuro. Un altro risultato della tesi é lo studio delle configurazioni di equilibrio in diversi mercati, con riferimento a quante imprese decideranno di intraprendere RSI e quante decideranno di non farlo.