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This research presents results of the last three years collaboration between the Centro di Ricerca ''E.~Piaggio'' and the company Ingegneria dei Sistemi SpA (IDS), on the application of game theoretic algorithms. Based on the results obtained by this research, IDS has decided to investigate the implementation of the proposed system on board of its unmanned vehicles, in order to provide a novel security system to the market. This research proposed the application of a coordinated multi robot system to the problem of asymmetric threat, both in military and civilian scenarios. The problem of detecting and accordingly reacting to an asymmetric threat (Asymmetric threats or techniques are a version of not ''fighting fair,'' which can include the use of surprise in all its operational and strategic dimensions and the use of weapons in ways unplanned) is a challenge both from research and technological points of view. Even though the available surveillance sensors are sufficient to identify and classify asymmetric threats, they are able to give a quick alert only in nominal working conditions. Indeed, adverse weather conditions easily lead to degradation of sensors performance leading to a drastic reduction of the time available for a possible reaction after the detection, identification and classification procedures. The short time--to--reaction may increase the possibility of human errors especially in stressful situations (e.g. an incorrect assessment of the necessary reaction). This research proposes the use of multi--robot coordinated team as autonomous surveillance systems that can guarantee an adequate supervision of the area in any working conditions even though the entire area is not fully monitored at any time instant. Indeed, the mobility abilities of autonomous vehicles can be exploited to deploy the team of robots to monitor the environment and to react to possible intruders. In particular, this research is focussed on the problem of coordinating a team of robots based on partial knowledge of the environment due to limited sensors footprint and communication range. The coordination of the robot must also guarantee the accomplishment of other tasks in a framework in which communication is limited due to security issues or deteriorated communication channels (e.g. underwater scenarios). An example of antagonistic tasks is the monitoring of the area around the main ship while detecting, tracking and herding an intruder toward a safe area. It is worth noting that the marine scenario is only a possible application of the proposed methodology that is valid whenever the goal is to detect, localize and react to any environmental changes of interest, e.g. high variation of temperature, water pollution, terrorists attacks, etc. In this research a unified model has been proposed for the problem under study for different application scenarios such as asymmetric threats protection in marine environments and safety at border crossing points, such as airports. The proposed unified framework is based on the Game Theory. Indeed, it is well known that the particular class of potential games solves several cooperative control problems with a reduced amount of communication between robots. In particular, the considered control problem is transformed into a non--cooperative game where the goal is to reach specific equilibria. Moreover, the case of ``payoff--based'' scenarios, where robots get a reward in the reached regions based on the action performed by other robots, helps in capturing the requirements into the problem formulation. Learning algorithms that can steer the robots toward Nash equilibria are proven to solve partially the problem. In case of a static environment, e.g. fixed area of interest in the scenario, the coverage problem has been largely studied with a game theoretic approach. However, such algorithms are proven to converge to a static configuration maximizing the number of interested area covered by the robot sensors' footprint but are not able to handle a dynamic intruder. On the other hand, in case of dynamic environment, as for asymmetric threat protection, existing algorithms have been only designed to explore the entire area without selecting the sub--regions of major interest or doing it with high communication costs. Concluding, with respect to the state of the art literature, in this research, a game theoretic approach is used to detecting, track and herd a dynamic intruder protecting pre-defined areas. In particular, the work proposes two kind of coordination protocols which are proved to solve the asymmetric threat protection problem. Based on the well--known payoff--based algorithms, the research presents some extension of state--of--the--art coordination protocols which are suitable for dynamic environment. Moreover, the work presents new payoff--based algorithms to deal with the problem of multi--robot coordination in dynamic environment where the robots must accomplish antagonistic tasks simultaneously. For those new algorithms convergence to equilibria is formally proved. Finally, our research is interested in investigating the relationship between the team of guards and the intruder once it has been identified, i.e, the \emph{reaction phase}. Such problem is investigated with the use of a game theoretic framework and, a novel team coordination protocols for the intruder herding problem, is proposed. Such new algorithm solves the problem of steering a team of guards for guiding an intruder towards a restricted area of a known environment. The proposed system, based on the virtual objectives concept, is able to limit the movement of an intruder without communication between robots of the team. Proposed framework has been validated with a Monte Carlo simulation in order to cover a large set of different situations. Based on Monte Carlo simulation, a novel tool, that solves the problem of determine the minimum number of robots contrasting an intruder which is moving in the area, is proposed. Indeed, it can be used to determine the maximum volume to store autonomous vehicles on board. Proposed algorithms have been evaluated against intruders piloted by human, in order to test the robustness of the proposed solution. The proposed game theoretic framework has been tested in real robot experiments thanks to the use of a novel multi--robot system for managing team of robots. Based on the promising results, the proposed model has been extended to cope the asymmetric threat protection problem when sensors are affected by uncertainty on the detection. Video of some validation results are available online (https://youtu.be/emyf4xx-_pY, https://youtu.be/rBs23CNdh8U and https://youtu.be/ODoHY7WgQdc).

La ricerca proposta si pone l'obiettivo di definire e sperimentare un metodo per un'articolata e sistematica lettura del territorio rurale, che, oltre ad ampliare la conoscenza del territorio, sia di supporto ai processi di pianificazione paesaggistici ed urbanistici e all'attuazione delle politiche agricole e di sviluppo rurale. Un'approfondita disamina dello stato dell'arte riguardante l'evoluzione del processo di urbanizzazione e le conseguenze dello stesso in Italia e in Europa, oltre che del quadro delle politiche territoriali locali nell'ambito del tema specifico dello spazio rurale e periurbano, hanno reso possibile, insieme a una dettagliata analisi delle principali metodologie di analisi territoriale presenti in letteratura, la determinazione del concept alla base della ricerca condotta. E' stata sviluppata e testata una metodologia multicriteriale e multilivello per la lettura del territorio rurale sviluppata in ambiente GIS, che si avvale di algoritmi di clustering (quale l'algoritmo IsoCluster) e classificazione a massima verosimiglianza, focalizzando l'attenzione sugli spazi agricoli periurbani. Tale metodo si incentra sulla descrizione del territorio attraverso la lettura di diverse componenti dello stesso, quali quelle agro-ambientali e socio-economiche, ed opera una sintesi avvalendosi di una chiave interpretativa messa a punto allo scopo, l'Impronta Agroambientale (Agro-environmental Footprint - AEF), che si propone di quantificare il potenziale impatto degli spazi rurali sul sistema urbano. In particolare obiettivo di tale strumento è l'identificazione nel territorio extra-urbano di ambiti omogenei per caratteristiche attraverso una lettura del territorio a differenti scale (da quella territoriale a quella aziendale) al fine di giungere ad una sua classificazione e quindi alla definizione delle aree classificabili come "agricole periurbane". La tesi propone la presentazione dell'architettura complessiva della metodologia e la descrizione dei livelli di analisi che la compongono oltre che la successiva sperimentazione e validazione della stessa attraverso un caso studio rappresentativo posto nella Pianura Padana (Italia). ; The research aims to define, test and validate a methodology for a comprehensive and systematic analysis of the countryside, suitable to broaden the knowledge of the rural landscape, and support the landscape and urban planning process and the implementation of rural development policies. An in-depth study of the state of the art concerning the evolution of urbanisation processes and their consequences in Italy and Europe, analysis of local and regional policies focused on rural and suburban areas, and of the scientific literature in the field of spatial analysis methodologies, have allowed the definition of the basic concept of the research. A multi-criteria and multi-level methodology for the analysis of rural areas has been developed in a GIS and tested on a case study. The proposed method is based on clustering algorithms and maximum-likelihood classification techniques, and focuses on periurban agricultural areas. The method allows to achieve an objective synthesis of the several variables selected and defined to cover various agro-environmental and socio-economic landscape components, by means of an innovative interpretative key, the "Agri-environmental Footprint (AEF)", which aims to quantify the potential impacts of rural areas on the urban system. The specific goal of the proposed methodology is to identify homogeneous extra-urban areas through their objective characterisation at different scales (from the territorial to the farm level), in order to classify the whole rural landscape, and in particular to identify peri-urban agricultural areas. The thesis presents the overall architecture of the proposed methodology and the in-depth description of its levels of analysis. The method is then tested and validated on a representative case study in the Po Valley (Italy).

Housing tenure structures differ considerably across OECD countries. Typically, the share of owner-occupied housing is very high in Southern European countries (Spain, Italy, Greece), while relatively low in Austria, Germany, France, the Netherlands and in some Nordic countries such as Sweden, Finland and Denmark (see Catte et al. [2004]). This share has increased in most OECD countries during last two decades. Italy, Spain, Portugal, the Netherlands and Belgium registered the largest increases from the eighties to the mid of the first decade of the century. In the UK, the homeonwership rate increased steadily up to 2005, then dropped sharply in the last few years. High homeownership rates and their increments have been in part determined by pro-ownership policies implemented throughout most OECD countries. Such policies can take the vest of tax reliefs for mortgage interest payments, exemptions for capital gains taxation applied to residential property, or generous subsidies for low-income families to reduce the costs of homeownership. Although the orientation of several governments, particularly in Europe, has been to promote homeownership, economists have raised several concerns about the consequences of large homeownership shares on the functioning of the labour market. The analysis of the relation between the housing tenure and the labour market dates back to mid-nineties, when Andrew Oswald pinned on high homeownership rates the blame for the high unemployment rates in Europe (Oswald [1996], Oswald [1997], Oswald [1999]). Making use of aggregate data, Oswald found a strong positive statistical association between the two rates at the international and regional level. Thus, his receipt to reduce unemployment was strikingly at odds with the prevailing political wisdom: "We can put Europe back to work . . . by reducing homeownership" (Oswald [1999])1. Oswald identified five mechanisms that drive the positive impact on unemployment. These are mostly related to the idea that the mobility constraints imposed by homeownership introduce frictions in the labour market which harm its efficiency. The first and most important, is a direct effect. Owner occupiers incur higher transaction costs for selling home and moving to a new accommodation, which can be even higher whenever capital gains for houses are taxed and there are no exemptions. The other four mechanisms can be thought as externalities of homeownership. Second, where the rental market is thin, everyone, regardless of the housing tenure, can have difficulties in finding the accommodation close to the job they aspire to, so that efficient job matches are hindered. This is the case even for mobile people who would be happy to move for job reasons, such as young still living in the family-home in a kind of free-rent status. Third, owning the accommodation hampers also job-to-job changes and prolong poor job matches hence harming the whole economic system efficiency. Fourth, owner-occupiers are more likely than renters to lobby for deterring entrepreneurs from investing in their residential area. Fifth, since owners commute much more than renters, and over longer distances, higher homeownership rates in the area lead to higher transport costs and possibly to congestion costs, which make getting to work more costly for everyone and act as a sort of unemployment benefits in increasing the relative attractiveness of not working. Although the argument underlying a positive relationship between homeownership and unemployment originates from macroeconomic evidence, its theoretical foundations are mainly microeconomic and a vast part of the empirical research carried out subsequently has been based on micro data. The typical test of the so-called "Oswald thesis" consists in estimating the homeownership effect on the duration of the unemployment spell or, less often, on the probability to be unemployed. The expected sign is positive, along the main idea that higher mobility costs due to property holding reduce the willingness to accept job offers which require a residential move. Fewer studies, and only recently, have focused on the employment duration, testing whether homeownership can reduce job finding rates also for people already employed. Generally, empirical tests on micro data find no support for the Oswald hypothesis, and in most cases even that homeowners have shorter unemployment spells and lower likelihood to be unemployed, which are exactly counter-Oswald results. However, homeownership seems to increase job stability by hampering job-to-job changes for people already employed. As regards unemployment outcomes, the existing literature has put forward two possible reasons for the falsification of the Oswald hypothesis. The first one looks at the different effect of mobility costs on job search behavior in the local and in the non-local labour market. In fact, homeowners may have higher reservation wages for jobs which require a residential move (nonlocal market), but also lower reservation wages for jobs which do not (local market), so that job finding rates for the latter may be as high as to offset the lower rates for jobs in a distant area. Thus, whether the total job finding rate is lower for homeowners or for renters is just an empirical matter which depends on the magnitude of these two opposite effects. The second explanation points out the need for a refinement in the definition of the residential status. On the one hand, one should distinguish between owners who have to comply with mortgage payments and outright owners, as housing financial commitments can bear higher pressure to return to work or to keep on with the current job. For mortgage-holders, these financial constraints can counteract the effect of the reduced mobility due to ownership. On the other hand, unemployment outcomes can be different also for private and social renters. In fact, below-market rent, long waiting lists, security of tenure and the restricted transferability within social housing, can harm the relative performance of social renters. In this work, we aim at investigating the validity of the "Oswald thesis" taking into account the recent refinements by following both a theoretical and an empirical approach. The focus will be on UK micro data. In particular, we will make use of the two leading UK Surveys, the UK Quarterly Labour Force Survey and the British Household Panel Survey. In the first chapter, we investigate the relation between job search effort of unemployed and housing tenure. We test this relation focusing on the impact of the UK Jobseeker's Allowance reform introduced in the UK in October 1996, whose main aspect was a strengthening of search requirements for eligibility to the unemployment benefit. We revisit a simple model of search in which we introduce moving costs and housing costs to capture the two channels through which the degree of attachment to the accommodation influences search behaviour. Our theory suggests that a tightening in job search requirements, as implied by this reform, raises movements off benefit of non-employed with low search intensity and that this effect should adjust in size depending on the different housing tenure. We draw a dataset from the Labour Force Survey for the period 1995-1997, and by means of a Difference-in-Differences approach we analyze the impact of the reform on the claimant outflow. Average Treatment Effect estimates suggest that the impact of the reform is related to housing tenure. Specifically, renters account for a major portion of claimants who were crowded out of the benefit without finding a job, while the effect on outright owners and mortgagers is lower. Empirical evidence from our dataset clearly confirms that mortgagers search for a job more intensively than renters, as our model predicts. This latter finding is consistent with a higher estimated treatment effect for renters, since a high initial search intensity seems the key to insulate oneself from the impact of the tightening of search requirements. In the second chapter we attempt to reconcile the empirical evidence with the argument in favour of a negative effect of homeownership on exit rates from unemployment. Taking into account some likely reasons for the falsification of the Oswald's thesis, we provide evidence which supports it. At first, in a theoretical model of endogenous job search adapted to distinguish between local and non-local labour markets, we show that homeowners higher moving costs imply unambiguously lower search and lower job finding rates, even though an opposite effect works for jobs which do not require a move. Then, in the empirical analysis we make use of data drawn from the British Household Panel Survey to compare job search intensity measures by housing tenure. In defining the residential status, we distinguish between outright owners and mortgage-holders, and between social and private renters. We find that, controlling for housing costs and for the four-fold tenure definition, non-employed outright owners have definitely a lower attachment to the labour market than renters, and that this effect is even more evident when we compare them to private renters. In the third chapter, we analyse the impact of the housing tenure on labour market outcomes using individual data from the UK labour Force Survey. We estimate both a binary model for the probability to be unemployed and a hazard model for exits out of unemployment. In both models we test for endogeneity of housing tenure. In the binary model, exogeneity is rejected so we perform endogenous multinomial treatment effects estimates. In the hazard model, we find no evidence of unobserved heterogeneity thus estimates are performed assuming exogeneity. Results show that mortgagers have the lowest probability to be unemployed and the highest job finding rates, while social renters exhibit the worst performance. Whether private renters perform better than outright owners is a matter of debate: while we have no evidence in favour of this claim, the evidence in favour of the opposite is only modest.