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Entrepreneurial Behavior is Still a Black Box. Three Essays on How Entrepreneurial Learning and Perceptions Can Influence Entrepreneurial Behavior and Firm Performance.
No full textNowadays, entrepreneurship has received a large amount of attention in such studies as economics, sociology, finance, and public policy. Furthermore, The European Union and national government have implemented several policy interventions aimed to encourage new firm formation. Entrepreneurial education is now reinforced in schools, colleges, and universities. Nevertheless, entrepreneurship remains to be a black box. Making everyday decisions on firm organization and management is a complex process, which depends on how entrepreneurs perceive the environment and their own entrepreneurial abilities. These perceptions influence firm behavior that can be represented by combination of different actions.
The main goal of this doctoral thesis is to examine how entrepreneurial perceptions and learning influence entrepreneur preferences for certain actions and thus, how they affect firm performance. The first essay aims to understand whether the effectiveness of the policy is altered by the behavioral assumption that entrepreneurs are overconfident about their entrepreneurial abilities and tend to be overoptimistic in the evaluation of future prospects. The essay applies the agent-based model that is a modified version of the financial fragility model of Delli Gatti et al. (2005). The simulation results suggest that the presence of misperceptions of entrepreneurial abilities influence the policy outcomes. The main purpose of the second essay is to reveal how entrepreneurial perceptions of competitive environment influence their preferences for competitive strategies. Competitive advantages of firms are defined on the basis of Porter’s (1980) model of generic strategies — differentiation and cost leadership. The results of the analysis suggest that perceived threat of competition pushes firms to take actions. The preferences for actions are explained by available resources such as human capital. The third essay aims to evaluate the impact of capital grants given to microenterprises operating in the Province of Trento, Italy in 2009 and 2010. The last essay empirically illustrates how lack of restrictions imposed on the amount of possible subsidy requests and fixed eligibility criteria has invoked subsidy-seeking behavior of firms. The results from econometric analysis suggest that subsidies have not been able to improve firm performance or to increase firm size in 2011. However, a positive effect of subsidies on the propensity to invest in training and in marketing and advertising in 2012 has been detected
Essays on Responding to Climate Change, Social Protection, and Livelihood Diversification in Rural Ethiopia
No full textThe nexus between the environment and development is often analysed through the sustainable livelihoods framework and within this framework, livelihood diversification has dominated much of the literature on sustainable livelihoods in the late 1990s and early 2000s (see Tacoli, 1998; De Haan, 1999; Ellis, 2005). This literature shows that agriculture is not the only source of livelihood for rural people in developing countries and diversifying into non-farm activities is increasingly adopted as a viable livelihood strategy and growing in its importance. Since then however, diversification seems to have lost favour in both the academic and policy discussions. Recently, with climate change and the recognition of its adverse impacts on livelihoods at the forefront in the developing world, there is a revival of interest and discussion on diversification as one of the main strategies by which rural people can respond to the challenges of climate change.
This thesis is an effort to document local ways of responding to the impacts of climate change and how existing policy instruments at macro and meso level mainly social protection schemes contribute to the efforts already undertaken by individual households at micro level.
In view of this, the thesis contains four studies which provide theoretical and empirical analysis on non-farm diversification and the role of the Productive Safety Net Programme (PSNP) in climate change adaptation in rural Ethiopia.
The first study discusses the perceptions of smallholders’ towards climate variability and change as well as local adaptation strategies based on a case study of two districts in Northern Ethiopia. The study makes use of primary data gathered from focus group discussions and in-depth interviews with farmers and secondary data on key climate variables–rainfall and temperature and compares farmers’ perceptions with climate records. The results show that farmers perceive changes in their local climate and their overall perception matches with the results from rainfall and temperature trend analysis. The study also reveals that the greatest impact of these changes in rainfall and temperature are felt on the subsistence farming, which is already hard-pressed to meet the ever-inextricable challenge of food insecurity. Smallholders are also found to employ farm-level adaptation strategies combined with diversification. However, the current level of diversification appears to be dominated by natural resource-based strategies that may not be sufficient to deal with the impacts of current climate variability and expected changes.
The second study uses the Ethiopian Rural Household Survey (ERHS) over the period 1994–2009 to analyse the factors that determine participation and returns from non-farm activities in rural Ethiopia. This study uses both the number of activities and income to measure non-farm diversification and estimates a range of micro econometric models. The results suggest that many of the variables that determine non-farm diversification belong to pull factors and are therefore a reflection of accumulation strategies. Despite this dominant pattern, however, it is likely that the poor are also diversifying into non-farm activities to earn income during agricultural off-seasons to smooth consumption. The third study examines the impact of non-farm income diversification on income distribution and poverty using Gini–coefficient decomposition, fixed effects and probit models. These analyses reveal that non-farm income diversification has a positive impact on rural households’ welfare and income distribution. This result strengthens the argument that non-farm income diversification can be a good strategy to lessen agricultural risks. The fourth study uses a sub-sample of the ERHS for the period 2004 and 2009 to examine the impact of the Productive Safety Net Programme (PSNP) as the main social protection scheme on household non-farm income diversification as an adaptation strategy to climate change. This is an impact evaluation study that employs the Difference-in-Differences approach combined with Propensity Score Matching for a panel of 1306 rural households. The results indicate that receiving transfers from the PSNP, on average increases income from non-farm activities and confirms the hypothesis that social protection can promote positive adaptation strategies and serve as effective means of reducing the vulnerability of smallholders to climate change induced shocks
Assessing solar radiation components over the alpine region Advanced modeling techniques for environmental and technological applications.
No full textThis thesis examines various methods for estimating the spatial distribution of solar radiation, and in particular its diffuse and direct components in mountainous regions. The study area is the Province of Bolzano (Italy). The motivation behind this work is that radiation components are an essential input for a series of applications, such as modeling various natural processes, assessing the effect of atmospheric pollutants on Earth's climate, and planning technological applications converting solar energy into electric power. The main mechanisms that should be considered when estimating solar radiation are: absorption and scattering by clouds and aerosols, and shading, reflections and sky obstructions by terrain. Ground-based measurements capture all these effects, but are unevenly distributed and poorly available in the Italian Alps. Consequently they are inadequate for assessing spatially distributed incoming radiation through interpolation. Furthermore conventional weather stations generally do not measure radiation components. As an alternative, decomposition methods can be applied for splitting global irradiance into the direct and diffuse components. In this study a logistic function was developed from the data measured at three alpine sites in Italy and Switzerland. The validation of this model gave MAB = 51 Wm^-2, and MBD = -17 Wm^-2 for the hourly averages of diffuse radiation.
In addition, artificial intelligence methods, such as artificial neural networks (ANN), can be applied for reproducing the functional relationship between radiation components and meteorological and geometrical factors. Here a multilayer perceptron ANN model was implemented which derives diffuse irradiance from global irradiance and other predictors. Results show good accuracy (MAB in [32,43] Wm^-2, and MBD in [-7,-25] Wm^-2) suggesting that ANN are an interesting tool for decomposing solar radiation into direct and diffuse, and they can reach low error and high generality. On the other hand, radiative transfer models (RTM) can describe accurately the effect of aerosols and clouds. Indeed in this study the RTM libRadtran was exploited for calculating vertical profiles of direct aerosol radiative forcing, atmospheric absorption and heating rate from measurements of black carbon, aerosol number size distribution and chemical composition. This allowed to model the effect of aerosols on radiation and climate. However, despite their flexibility in including as much information as available on the atmosphere, RTM are computationally expensive, thus their operational application requires optimization strategies.
Algorithms based on satellite data can overcome these limitations. They exploit RTM-based look up tables for modeling clear-sky radiation, and derive the radiative effect of clouds from remote observations of reflected radiation. However results strongly depend on the spatial resolution of satellite data and on the accuracy of the external input. In this thesis the algorithm HelioMont, developed by MeteoSwiss, was validated at three alpine locations. This algorithm exploits high temporal resolution METEOSAT satellite data (1 km at nadir). Results indicate that the algorithm is able to provide monthly climatologies of both global irradiance and its components over complex terrain with an error of 10 Wm^-2. However the estimation of the diffuse and direct components of irradiance on daily and hourly time scale is associated with an error exceeding 50 Wm^-2, especially under clear-sky conditions. This problem is attributable to the low spatial and temporal resolution of aerosol distribution in the atmosphere used in the clear-sky scheme. To quantify the potential improvement, daily averages of accurate aerosol and water vapor data were exploited at the AERONET stations of Bolzano and Davos. Clear-sky radiation was simulated by the RTM libRadtran, and low values of bias were found between RTM simulations and ground measurements. This confirmed that HelioMont performance would benefit from more accurate local-scale aerosol boundary conditions. In summary, the analysis of different methods demonstrates that algorithms based on geostationary satellite data are a suitable tool for reproducing both the temporal and the spatial variability of surface radiation at regional scale. However better performances are achievable with a more detailed characterization of the local-scale clear-sky atmospheric conditions. In contrast, for plot scale applications, either the logistic function or ANN can be used for retrieving solar radiation components
Semantic Aware Representing and Intelligent Processing of Information in an Experimental domain: the Seismic Engineering Research Case
No full textSeismic Engineering research projects’ experiments generate an enormous amount of data that would benefit researchers and experimentalists of the community if could be shared with their semantics. Semantics is the meaning of a data element and a term alike. For example, the semantics of the term experiment is a scientific research performed to conduct a controlled test or investigation. Ontology is a key technique by which one can annotate semantics and provide a common, comprehensible foundation for the resources on the Semantic Web. The development of the domain ontology requires expertise both in the domain to model as well as in the ontology development. This means that people from very different backgrounds, such as Seismic Engineering and Computer Science should be involved in the process of creating ontology. With the invention of the Semantic Web, computing paradigm is experiencing a shift from databases to Knowledge Bases (KBs), in which ontologies play a major role in enabling reasoning power that can make implicit facts explicit to produce better results for users. To enable an ontology and a dataset automatically exploring the relevant ontology and datasets from the external sources, these can be linked to the Linked Open Data (LOD) cloud, which is an online repository of a large amount of interconnected datasets published in RDF. Throughout the past few decades, database technologies have been advancing continuously and showing their potential in dealing with large collection of data, but they were not originally designed to deal with the semantics of data. Managing data with the Semantic Web tools offers a number of advantages over database tools, including classifying, matching, mapping and querying data. Hence we translate our database based system that was managing the data of Seismic Engineering research projects and experiments into KB-based system. In addition, we also link our ontology and datasets to the LOD cloud. In this thesis, we have been working to address the following issues. To the best of knowledge the Semantic Web still lacks the ontology that can be used for representing information related to Seismic Engineering research projects and experiments. Publishing vocabulary in this domain has largely been overlooked and no suitable vocabulary is yet developed in this very domain to model data in RDF. The vocabulary is an essential component that can provide logistics to a data engineer when modeling data in RDF to include them in the LOD cloud. Ontology integration is another challenge that we had to tackle. To manage the data of a specific field of interest, domain specific ontologies provide essential support. However, they alone can hardly be sufficient to assign meaning also to the generic terms that often appear in a data source. That necessitates the use of the integrated knowledge of the generic ontology and the domain specific one. To address the aforementioned issues, this thesis presents the development of a Seismic Engineering Research Projects and Experiments Ontology (SEPREMO) with a focus on the management of research projects and experiments. We have used DERA methodology for ontology development. The developed ontology was evaluated by a number of domain experts. Data originating from scientific experiments such as cyclic and pseudodynamic tests were also published in RDF. We exploited the power of Semantic Web technologies, namely Jena, Virtuoso and VirtGraph tools in order to publish, storage and manage RDF data, respectively. Finally, a system was developed with the full integration of ontology, experimental data and tools, to evaluate the effectiveness of the KB-based approach; it yielded favorable outcomes. For ontology integration with WordNet, we implemented a semi-automatic facet based algorithm. We also present an approach for publishing both the ontology and the experimental data into the LOD Cloud. In order to model the concepts complementing the vocabulary that we need for the experimental data representation, we suitably extended the SEPREMO ontology. Moreover, the work focuses on RDF data sets interlinking technique by aligning concepts and entities scattered over the cloud
Drag-free Spacecraft Technologies: criticalities in the initialization of geodesic motion
No full textPresent and future space missions rely on systems of increasingly demanding performance for being successful. Drag-free technology is one of the technologies that is fundamental for LISA-Pathfinder, a European Space Agency mission whose launch is planned for the end of September 2015. A purely drag-free object is defined by the absence of all external forces other than gravity. This is not a natural condition and therefore a shield has to be used in order to eliminate the effect of undesired interactions. In space, this is achieved by properly designing the spacecraft that surrounds the object, usually called test mass (TM). Once the TM is subjected to gravity alone its motion is used as a reference for the spacecraft orbit. The satellite orbit is controlled by measuring the relative TM-to-spacecraft position and feeding back the command to the propulsion system that counteracts any non gravitational force acting on the spacecraft. Ideally, the TM should be free from all forces and the hosting spacecraft should follow a pure geodesic orbit. However, the purity of the orbit depends on the spacecraft’s capability of protecting the TM from disturbances, which indeed has limitations.
According to a NASA study, such a concept is capable of decreasing operation and fuel costs, increasing navigation accuracy. At the same time, a drag-free motion is required in many missions of fundamental physics. eLISA is an ESA concept mission aimed at opening a new window to the universe, black holes, and massive binary systems by means of gravitational waves. This mission will be extremely challenging and needs to be demonstrated in flight. LISA-Pathfinder is in charge of proving this concept by demonstrating the possibility of reducing the non-gravitational disturbance below a certain demanding threshold. The success of this mission relies on recent technologies in the field of propulsion, interferometry, and space mechanisms. In this frame, the system holding the TM during launch and releasing it in free-fall before the science phase represents a single point of failure for the whole mission. This thesis describes the phenomena, operations, issues, tests, activities, and simulations linked to the release following a system engineering approach. Great emphasis is given to the adhesion (or cold welding) that interferes with the release.
Experimental studies have been carried out to investigate this phenomenon in conditions representative of the LISA-Pathfinder flight environment. The last part of the thesis is dedicated to the preliminary design of the housing of the TM in the frame for a low-cost mission conceived at Stanford (USA). Analysis and results are through out presented and discussed. The goal of this thesis is a summary of the activities aimed at a successful LISA-Pathfinder mission. The ambition is to increase the maturity of the technology needed in drag-free projects and therefore provide a starting point for future fascinating and challenging missions of this kind
From Energy Efficient to Energy Neutral Wireless Sensor Networks
No full textEnergy autonomy for Wireless Sensor Networks (WSNs) is a key to involve industry stakeholders willing to spend billions on the Internet of Things. By offering the lifetime of only a few years, traditional battery powered WSNs are neither practical nor profitable due to their high maintenance cost. Powering WSNs with energy harvesters can overcome this limitation and increase mean time-to-maintenance to tens of years. However, the primary challenge in realizing an energy neutral operation is to reduce the consumed energy drastically to match with the harvested energy. This dissertation proposes techniques to minimize the overhead of two main activities: communication and sampling. It does so by making a key observation: a plethora of applications can accept low accuracy of sensed phenomenon without sacrificing the application requirements. This fact enables us to reduce consumed energy by radically revising the network stack design, all the way from the application layer to underlying hardware. At the application layer, the relaxed requirements make it possible to propose techniques to reduce the data exchanges among the nodes, the most power hungry operation in WSNs. For example, we propose a simple yet efficient prediction based data collection technique called Derivative-Based Prediction (DBP) that enables data suppression up to 99%. With the remaining ultra-low application data rate, a full system-wide evaluation reveals that the dominating overhead of the lower layers greatly limits the gains enabled by DBP. A cross-layer optimization of the network stack is then designed specifically to strip off the unnecessary overhead to gain one order of magnitude longer lifetime. Although a huge saving in relative terms, the resulting power consumption is still much higher than tens of microwatts, the power usually achievable from a reasonably sized harvester deployed in an indoor environment. Therefore, we consider a novel combination of hardware components to further reduce power consumption. Our work demonstrates that using wake-up receivers along with DBP results in long idle periods with only rare occurrences of power hungry states such as radio transmissions and receptions. Low power modes, provided by various components of the underlying hardware platform, are adopted in the idle periods to conserve energy. In concrete real-world case studies, the lifetime is estimated to improve by two orders of magnitude. Thanks to the software and hardware features proposed above, the overall power consumption is reduced to a point where the sampling cost constitutes a significant portion of it. To reduce the cost of sampling, we introduce the concept of Model-based Sensing in which we push prediction based data collection as close as possible to the hardware sensing elements. This hardware-software co-design results in a system that consumes only a few microwatts, a point where even harvesters deployed in challenging indoor conditions can sustain the operation of nodes. This dissertation advances the state of art on energy efficient WSNs in several dimensions. First, it bridges the gap between theory and practice by providing the first ever system-wide evaluation of prediction based data collection in real-world WSNs. Second, new software based optimizations and novel hardware components are proposed that can deliver three orders of magnitude reduction in power consumption. Third, it provides tools to estimate the harvestable energy in real WSNs. By using these tools, the work highlights that the energy consumed by the proposed mechanisms is indeed lower than the energy harvested. By closing the gap between supply and demand of energy, the dissertation takes a concrete step in the direction of achieving completely energy neutral WSNs
The Conflict-Cooperation Nexus. Politicisation, Security and Domestic Institutions in EU-Russia Energy Relations
No full textOver the last decade, EU–Russia gas relations have witnessed significant deterioration—the bilateral agenda has been narrowed down to ad hoc consultations, disputes over investment and long-term contract provisions have multiplied, and disagreements between the EU and Russia have significantly hindered the multilateral process of the Energy Charter Treaty (the ECT). This deterioration seems to be rather paradoxical in light of high gas interdependence between the EU and Russia and a rich history of well-established cooperation during the Cold War under profound ideological and strategic constraints. In addition, conflictual patterns in EU–Russia gas relations occurred in the beginning of the 2000s, during the period of high oil prices and growing global natural gas demand—the period when enhancement of cooperation would be a more expected outcome. Therefore, the core research question of the thesis addresses the puzzle: why, despite decades of cooperation during the Cold War between Western European countries and the USSR, have EU–Russia gas relations become conflictual since the 2000s? By answering this research question, the study seeks to contribute to the analysis of institutionalisation of energy relations and to reveal factors that lead to cooperative or conflictual outcomes. So far, IR research inquiries in the field have prioritised resource and normative determinisms in addressing the success or failure of energy cooperation, which assume a geopolitical-realist struggle for energy resources and a priori benevolence of free markets in line with the neoliberal economic agenda respectively. The broader geopolitical approach has explained energy conflicts by structural factors of unequal resource allocation across the world and attributed a direct impact of a state resource base (an energy-rich or energy-poor state) on states’ behaviour in the international arena. Another strand of the literature, ‘the market approach’, has also viewed problematic cooperation as a result of different interests of energy producers and consumers—but from a slightly different perspective. Limited institutionalisation of interactions has been explained by different models of gas markets producers and consumers choose. Thus, consumers favour a model of the competitive liberalised gas market (a market actor model), while producers would opt for a model of vertically-integrated monopoly and resource nationalism (a geopolitical actor model) in order to preserve control over resources. Pointing to a number of opposite cases, this study disregards the straightforward assumption that there is a direct link between a resource base and states’ strategies in the international arena. Bringing domestic conditions back to these debates, the study argues that increasing differences between the EU and Russia’s domestic institutional models of the gas market have been the main factor that has triggered conflictual patterns in EU–Russia gas relations since the 2000s. These domestic institutional changes have replaced attempts to build a strategic partnership with ad hoc consultations at the level of practical implementation, and have triggered broader deinstitutionalisation of multilateral gas governance in Europe. The three case studies analyse three instances of EU–Russia gas relations, tracing the crucial differences to determine the outcome—cooperation (a creation of a new or enhancement of an existing international institution), institutionalised conflict (disagreements regarding institutional settings of interactions, which are discussed and settled within the procedures of pre-existing or negotiated international institutions), or institutional conflict (expansion of disagreements beyond the pre-existing or negotiated framework of international institutions, which are no more accepted by the parties for conflict resolution) between the parties. The thesis contributes to ongoing debates about the impact of domestic institutions on actors’ policy strategies in the international arena, bringing insights from energy economics, energy law, and regulatory studies to IR. It argues that differences in domestic models under conditions of high interdependence might lead to politicisation of gas market issues and broader aspects of energy governance. The study also enriches debates about energy security, arguing that energy security depends also on a stable and predictable institutional framework for interactions, which inter alia requires compatibility of actors’ domestic models
Vescovi, re, imperatori: Anastasio Bibliotecario tra Occidente e Oriente
No full textLa tesi di dottorato ha l'obiettivo di indagare la corrispondenza di Anastasio Bibliotecario, la cui attività a Roma raggiunse il culmine tra gli anni Sessanta e Settanta del IX secolo: egli fu collaboratore di tre papi, ebbe contatti con gli imperatori Ludovico II e Carlo il Calvo, fu ottimo conoscitore della lingua greca e della cultura bizantina e intermediario da un lato tra mondo franco e papato, dall’altro tra imperatore d’Occidente e imperatore d’Oriente. Nelle lettere anastasiane, sia in quelle scritte in maniera autonoma, sia in quelle readatte svolgendo incarichi più o meno ufficiali, è possibile individuare linguaggi, metafore, espressioni, citazioni, stili di volta diversi a seconda dei destinatari: tra questi, Adone di Vienne e Incmaro di Reims; Carlo il Calvo e Ludovico II, con il quale Anastasio sembra tessere una lunga e intensa collaborazione; e infine l’imperatore d’Oriente Basilio I. Poiché Anastasio fu coinvolto nelle principali questioni della metà del IX secolo, le lettere anastasiane nascono in contesti estremamente eterogenei: le problematiche questioni sorte tra i vescovi franchi (in particolare, per quanto riguarda il conflitto fra Incmaro di Reims e il nipote omonimo vescovo di Laon); i rapporti tra papato e Carolingi nella gestione degli affari interni ai regni e nella questione dell’incoronazione imperiale; i complessi rapporti fra Oriente e Occidente nella definizione dell’equilibrio delle funzioni dei due imperatori e della politica nel sud Italia; le tensioni generate dallo scisma di Fozio. All’interno di questi contesti, l'analisi delle lettere anastasiane permette quindi di individuare di volta in volta le diverse scelte comunicative rispondenti a specifiche scelte e linee politiche. Per visulizzare il testo greco è necessario istallare il font Hellenica
The Neural Representation of Polysemy: The Case of Dot-objects
No full textAbstract and concrete concepts are generally considered fundamentally distinct categories. However, many concepts have both concrete and abstract senses, for instance "book" can refer to both a physical object (as in "a torn book") and the abstract content (as in "an interesting book"). How is the meaning of such concepts represented in the brain? In this thesis, we address this question in the light of Pustejovsky’s dot-object hypothesis (Pustejovsky, 1995, 2011). According to the hypothesis, words such as "book" and "lunch" are dot-objects: a class of logically polysemous words which have multiple senses that are closely bound together. As a result of the close binding, both senses can be accessed simultaneously (as in "read the book"), however sometimes only a single aspect is emphasised by the context (e.g. "the book burned", "he summarised the book").
We argue that the complex meanings of the dot-objects are represented and manipulated in semantic hubs in the brain, where all aspects of conceptual knowledge converge and are represented in a modality-independent manner (thus accommodating diverse aspects of knowledge such as that cakes are made of pastry and are related to both birthdays and diabetes). We present three experiments investigating the neural representation of three dot-object categories with clear concrete and abstract senses: print matter such as "book" (OBJECT • INFORMATION), meal concepts such as "lunch" (FOOD • EVENT), and institution such as "church" (BUILDING • ORGANISATION). In all the experiments, participants read the dot-objects in a minimal context which elicited either the concrete or the abstract interpretation (e.g. "open the book" / "consult the book", "cook the lunch" / "organise the lunch"). We found the neural distinction between the concrete and abstract interpretations of the dot-objects differed from the concrete-abstract distinction observed for mono-sense nouns; instead the differential effect was most evident in the anterior temporal lobe (ATL), an area argue to be the semantic hub. The result suggests that 1) the distinct senses of a dot-object are associated with a single, unspecified structure in the mental lexicon, thus aligning with the dot-object theory; 2) when in context, the semantic representation is specified by instantiation to a particular sense. In addition, we also observed variations between the book-like and the lunch-like dot-objects, suggesting a graded representation mechanism within the ATL. Finally the third experiment showed that the MEG gamma-band frequency power could distinguish the neural correlates of the concrete and abstract interpretations; notably the divergence occurred 400ms and later post-stimulus onset. Given the established role in the literature of the gamma-band in integration processes, we conclude that the meaning instantiation only occurred at the later integration stage
The Arousing Risk: Influences of positive and negative arousal on preferences for economic risk
No full textStandard economic models explain decision making under risk as a utility maximization process. Developments in cognitive psychology and neuroeconomics showed the volatility of such conceptualization highlighting human bounded rationality and discussing the role of decision maker’s affective state (basic reactions to any emotionally charged event) in cognitive evaluation of risk (risk as feeling). In particular, an affective-based evaluation of choice options may determine whether decision maker’s behavior will be risk averse or risk seeking. Evidence indicates that affective reactions carry over significant information about the goodness of certain choice options directly influencing risk taking behavior. Affective influences on decisions may be directly associated with the evaluation of the choice options and the anticipation of future outcomes (integral affect) or may be associated with stimuli or event unrelated to the decision at hand, for example contextual factors or environmental cues (incidental affect). A classic advertisement strategy, such as a smiling face presented in association with a good, is an example of contextual affective manipulation. Research shows that experiencing a positive affective state may lead to risk aversion behavior while negative affect may lead to risk seeking. However, previous studies mostly adopted a valence-based approach to the study of affect ignoring its multidimensional nature. In particular, the role of arousal has been largely neglected. Recent studies showed that emotional states with the same valence may have opposite consequences on risk taking. Therefore, the main purpose of the series of studies described in this dissertation was to investigate the effect of inducing incidental affective states at high and low levels of negative arousal or positive arousal on preferences for monetary options varying in risk. Research shows that elevated arousal is associated with cognitive depletion, increased sensitivity to rewards, immediate gratification, less resistance to temptation. Therefore, we hypothesized that affective states characterized by high levels of arousal might increase preferences for the riskier option. We further predicted that including arousing stimuli as contextual factor of a decision scenario would capture individual attention interfering with information processing of risk. In order to achieve this goal, in a first series of experiments we asked participants to make choices between couples of two-outcomes lotteries with the same expected value but different risk. Arousal was manipulated by presenting participants with visual stimuli (IAPS pictures) varying in the level of arousal (high or low) keeping the valence unvaried (negative or positive). By adopting the technique of contextual priming, participants were simultaneously exposed to stimuli (the lotteries) and the contextual factor (the arousing/unarousing image). An effect of arousal on predicting risky choice was found. Probability of selecting the riskier lottery was higher when an arousing stimuli (unpleasant or pleasant) was included as part of the decision context. In some cases, positive arousal was found to interact with gender: risk taking was higher in males than females when a pleasant arousing cue was presented. In a second series of studies, participants performed the same task and, by using an eye tracker, eye fixations and looking times were recorded. The predicted effect of arousal on attention was found. Participants spent more time looking at the arousing image (unpleasant or pleasant). This result is in line with arousal theories which correlate the level of arousal to attention allocated to the arousing stimuli. Furthermore, participants seemed to process less risky information (as indicated by decreased looking times toward the riskier option) when the arousing stimuli was contextually presented, as opposed to when the unarousing stimuli was presented