Bayesian Analysis of Social Influence

The network influence model is a model for binary outcome variables that accounts for dependencies between outcomes for units that are relationally tied. The basic influence model was previously extended to afford a suite of new dependence assumptions and because of its relation to traditional Markov random field models it is often referred to as the auto logistic actor-attribute model (ALAAM). We extend on current approaches for fitting ALAAMs by presenting a comprehensive Bayesian inference scheme that supports testing of dependencies across subsets of data and the presence of missing data. We illustrate different aspects of the procedures through three empirical examples: masculinity attitudes in an all-male Australian school class, educational progression in Swedish schools, and un-employment among adults in a community sample in Australia

Modelação geográfica da fragmentação e conectividade de habitats: casos de estudo nos padrões de distribuição local de espécies selvagens

Habitat fragmentation and the resultant reduction in connectivity are process of major importance in the persistence and patterns distribution of wildlife species. This thesis focuses on habitat fragmentation and connectivity, assessing their consequences on the local patterns distribution of wildlife species. The cases studies were published and conducted with monitoring data systematized using a common database. The case studies were located in the Alentejo region between the years of 1995 and 2005. The case studies are supported by examples of local impacts of fragmentation on the habitat connectivity of birds and reptile species patterns distribution. The observed pattern-process interactions are assessing by geographic modeling techniques. Methodologies were developed based on the innovative application of spatial statistical and networks analysis. The results show that the geographic modeling represents an added value to the understanding pattern-process interactions. The findings show how much the local distribution patterns of individuals are affected by habitat disturbances; RESUMO: A fragmentação dos habitats e a conectividade são processos de importância maior na persistência e nos padrões de distribuição das espécies selvagens. Esta tese centra -se na avaliação da fragmentação e conectividade dos habitats nos padrões locais de distribuição de espécies selvagens. Para tal foram realizados casos de estudo, com dados relativos a monitorizações efectuadas no Alentejo entre os anos de 1995 e 2005 e sistematizados numa base dados. Os casos de estudo foram publicados e são suportados por exemplos de impactes locais no padrão de distribuição de espécies de aves e réptil. Foram utilizadas técnicas de modelação geográfica na descrição e avaliação dos processos e padrões observados. Aplicadas e desenvolvidas metodologias inovadoras, com o suporte de técnicas de estatística espacial e análise de redes. Os resultados mostram que a modelação geográfica representa uma maisvalia para a compreensão da dinâmica entre padrões-processos. Os resultados revelam o quanto, os padrões de distribuição local dos indivíduos são afectados pelas alterações nos habitats

Setting the Agenda for AI: Actors, Issues, and Influence in United States Artificial Intelligence Policy

As research and adoption of artificial intelligence (AI) has significantly advanced in the early 21st century, determining how to govern AI has become a global priority. Key questions include how AI should be understood as a policy domain, which policy problems are most pressing, which solutions are most viable, and who should have a say in this process. This dissertation seeks to provide key insights into the early years of AI policy, focusing on the development of the emerging AI policy agenda in the United States. To do so, it examines and reveals which issues, actors, and influence efforts are playing a prominent role in the complex, ambiguous, and contested process of agenda-setting. The research performed draws on a variety of quantitative and qualitative methodologies, including document analysis, text-as-data and time series approaches, and experimental techniques. Data examined include text from U.S. federal AI policy documents, traditional and social media discourse from federal policymakers, media, and members of the public, and engagement data collected from state legislators who participated in a field experiment. The results reveal that social and ethical dimensions of AI receive a heightened degree of attention in AI policy discourse. However, consideration of these issues remains partially superficial and subsumed into concern about AI's potential for economic innovation and role in geopolitical competition. Further findings demonstrate that policy entrepreneurs can use persuasive narratives to influence legislators about AI policy, and that these narratives are just as effective as technical information. Finally, despite pervasive calls for public participation in AI governance, the public does not appear to play a key role in directing attention to AI's social and ethical implications nor in shaping concrete policy solutions, such that the emerging AI agenda remains primarily expert-driven. The dissertation's findings and theoretical and methodological approaches offer key contributions to policy process scholarship and related fields of research, and provide a baseline on which to understand the evolution of the AI policy agenda and AI governance going forward.Ph.D

Network adjacency in shaping intra-organizational perceptions about strategic IT-business alignment

Informaatioteknologian (IT) ja liiketoiminnan välinen strateginen yhteensovittaminen on ollut IT-johtajien huolena jo vuosikymmenten ajan. Yksi mahdollinen syy tähän voi olla se, että yritysten sisällä on usein suuria näkemyseroja yhteensovittamisen tasosta ja tilasta. Tutkimuksen tavoitteena oli tunnistaa näkemyserojen syntyyn vaikuttavia tekijöitä. Tutkimuksessa IT:n ja liiketoiminnan yhteensovittamista koskevia näkemyksiä tarkasteltiin sekä muodollisten organisaatiorakenteiden että todellisten vuorovaikutussuhteiden avulla. Lisäksi tavoitteena oli etsiä vaihtoehtoisia selityksiä näkemyseroille mm. yhteisen tietämyksen asteesta, samankaltaisista taustoista liittyen ikään, sukupuoleen, koulutukseen ja yrityksen palveluksessa vietettyyn aikaan, sekä tuoreeseen IT-päätökseen liittyvistä kokemuksista. Tutkimusmenetelmänä käytettiin sosiaalisen verkostoanalyysin kvantitatiivisia menetelmiä yhden empiirisen tutkimusasetelman puitteissa. Tiedot kerättiin kyselylomakkeen avulla energiatoimialalla toimivan yrityksen johdolta, IT-henkilöstöltä sekä heidän kanssaan tiiviissä vuorovaikutussuhteissa olevilta henkilöiltä. Todellisten vuorovaikutussuhteisten selvittämisessä käytettiin sosiometrisia kysymyksiä. Tulokset osoittavat, että organisaation osastorakenteella on merkittävä vaikutus näkemysten samankaltaisuuteen. Tärkeä tekijä näkemysten samankaltaisuuden muodostumiselle on myös henkilöiden välinen työasioihin liittyvä keskustelu- tai neuvonantosuhde, jonka ei tarvitse noudattaa muodollista organisaatiorakennetta. Sen sijaan ystävyyssuhteet tai osastorajoja rikkovat muodolliset organisaatiorakenteet eivät osoittautuneet merkittäviksi tekijöiksi. Myöskään vastaajien ikä, sukupuoli, koulutus tai yrityksen palveluksessa vietetty aika eivät näyttäneet vaikuttavan näkemyksiin tai niiden samankaltaisuuteen. Sitä vaston kokemukset juuri toteutetusta IT-päätöksestä osoittautuvat tärkeiksi tekijöiksi sille, millaiseksi IT:n ja liiketoiminnan yhteen sovittaminen koettiin. Tutkimus korostaa IT:n ja liiketoiminnan strategisen yhteensovittamisen sosiaalista ulottuvuutta ja tarjoaa tiedeyhteisölle uuden tutkimussuunnan lisäämällä IT:n ja liiketoiminnan yhteensovittamista koskevaan tutkimukseen yksilöiden väliset suhteet. Erityisesti työasioihin liittyvä vuorovaikutussuhde on yhteensovittamista koskevan tutkimuksen kannalta uusi merkittävä käsite. Liikkeenjohdon näkökulmasta tutkimustulokset korostavat verkostodynamiikan tunnistamisen tärkeyttä yhteensovittamista koskevien näkemysten muodostumisess

A estrutura de interação de um sistema e-territorial: território, mercado de habitação e econometria espacial

The notion of space (abstract, mathematical), inherent to territoriality, characterizes the conventional analytical tools used in planning. However, the approach to dimensionality and geometry within these tools has been questioned. The literature review suggests the need to develop analytical mechanisms, able to relax the geometric and dimensional reference framework that has been adopted in planning decision-making tools. The development of new spatial analysis methods, within spatial econometrics as well as other disciplines which are relevant for territorial planning, provides an opportunity to review the geometric and dimensional notions and the usually applied empirical estimation strategies. Taken hierarchy as a fundamental feature to specify the interaction structure that describes territorial systems, a minimum analytical condition is adopted that supports a new analytical framework, free of strong geometric and dimensional constraints. The research program presented here is based on the codification of spatio-territoriality in housing values, in addition to the relevance of housing price models themselves in territorial planning, motivating the study of the housing market in the case-study of the Aveiro-Ílhavo territorial system. The scientific knowledge about spatial interaction structures is combined with empirical insights, from a new methodology based on simpler econometric methods. It was possible to observe that territorial interaction structures are a combination of classical geographic patterns with an unknown geometry and unknown dimensionality. The results, framed by the theoretical discussion, support the observation of territorial restructuring processes, which arise, among other factors, from the changing role of new information and communication technologies. They also reinforce the adoption of the concept of e-Territorial (local) system to frame these new territorial structural properties.A noção de espaço (abstrato, matemático), subjacente à territorialidade, constitui a base das ferramentas analíticas convencionais, usadas em planeamento. Contudo, a dimensionalidade e geometria, subjacentes a essas ferramentas, têm vindo a ser questionadas. De facto, a revisão da literatura evidencia a necessidade de desenvolver mecanismos analíticos, capazes de relaxar os referenciais geométricos e dimensionais, adotados ao longo do processo de tomada de decisão no planeamento territorial. O recente desenvolvimento de novos métodos de análise espacial, quer no âmbito da econometria espacial, quer noutras disciplinas de suporte ao planeamento, constitui uma oportunidade de rever as assunções geométricas e dimensionais adotadas, bem como as respetivas estratégias de análise das estruturas territoriais que lhe estão subjacentes. Assumindo a hierarquia como uma propriedade fundamental na organização das interações dos sistemas territoriais, considera-se esta como uma condição mínima analítica, a partir do qual se propõe um novo referencial de estimação, mais liberto das condicionantes geométrica e dimensionais usuais. Neste contexto, assumindo que as propriedades espácio – territoriais são codificadas no valor habitação bem como a relevância do tema no planeamento territorial, adota-se o mercado de habitação no sistema territorial de Aveiro – Ílhavo enquanto caso de estudo. Cruzando as sugestões da literatura científica com os resultados de uma metodologia, de base econométrica, aplicada nestes contextos, observa-se que as estruturas de interação territorial fundem os padrões geográficos expectáveis (dos modelos clássicos) com um conjunto de relações de geometria e dimensionalidade desconhecida. De facto, tendo presente o quadro teórico que aponta para a reestruturação territorial como um elemento transformador associado às novas tecnologias de informação e comunicação, as evidências encontradas vêm reforçar a perceção teórica de que se encontram a despoletar os novos sistemas (locais) e-Territoriais.Programa Doutoral em E-Planeament