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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
601

THE EFFICACY OF AND PREFERENCE FOR CHOICE IN TOKEN ECONOMIES DURING RESPONSE ACQUISITION

Washa, Alexis 01 May 2016 (has links)
The present study evaluated preference for choice and its effect on motivation during response acquisition of receptive identification targets in children diagnosed with autism. Prior to the study a multiple stimulus without replacement preference assessment was conducted in order to determine the highly preferred stimulus. Choice was evaluated during a high-preferred, free-choice, and control condition for each participant. During the high-preferred condition, participants were only able to work for the high-preferred stimulus identified during the MSWO. During free choice, participants could choose among the five items presented in the MSWO, and during control each participant was unable to exchange his or her tokens for reinforcement. Choice was also evaluated during a concurrent-chain arrangement, where each participant was able to choose the condition he or she wanted to work under. The results showed that two out of the three participants did not show differentiation during the acquisition phase; however, during the concurrent-chain phase, all three participants demonstrated a stronger preference for free choice.
602

THE INTERACTION BETWEEN FUNCTION AND MACHINE PREFERENCE IN SLOT MACHINE GAMBLERS

Cronin, Anna Elizabeth 01 December 2014 (has links)
Gambling is a popular pastime in the United States, and it is important that we understand the class of behaviors in a behavior analytic context. The relationship between the function and preference of gambling behavior remains yet to be explored. The purpose of these two studies is to examine this relationship. Participants were asked to play a set of four computerized slot machines. Each slot machine was tied to a separated function-based outcome which they could win. In study 1, 80% of participants had a distinct preference for a single outcome. In study 2, the participants were also administered the GFA. Seven participants completed the MSWO. The relationship between the results of the GFA and the results of the free operant preference assessment did not support the hypothesis. Among other results, was data suggesting that those who score 0's on their GFA's may significantly affect the data and that the MSWO and free operant preference assessment have a strong high correlation.
603

FUNCTIONAL RESPONSE OF TEMNOCHILA VIRESCENS, EFFECT OF COMPETITION WITH THANASIMUS DUBIUS ON ADULT IPS GRANDICOLLIS SURVIVAL, AND DETERMINATION OF PHEROMONE PREFERENCE TYPES

Chism, Scott B. 01 August 2013 (has links)
Arthropod predators are able to influence the population dynamics of forest insects such as bark beetles. Two common predators of bark beetles are Temnochila virescens (F.) (Coleoptera: Trogositidae) and Thanasimus dubius (F.) (Coleoptera: Cleridae). Studies on T. virescens ecology have been few and not quantitative. Also, in recent years there has been increased focus on multiple-predator effects on the population dynamics of a single prey species, which better describes a natural system. Therefore, a series of three studies was conducted to provide a general overview of T. virescens ecology and its potential use for biological control. The first study examined the functional response of T. virescens toward its Ips prey. The second evaluated the impacts of intraguild competition between T. virescens and T. dubius adults on predation of a mutual prey species, I. grandicollis. The third determined if there were differences in pheromone preference among individual T. virescens adults. To evaluate the functional response, T. virescens and Ips grandicollis (Eichhoff) adults were combined in varying densities. Ips grandicollis survival was assessed by examining the number of prey eaten in relation to predator and prey densities. I found that a type II functional response model incorporating interference provided a good fit for the data. The interference was strong enough that a ratio-dependent model fit the data just as well as the full model. The effect of competition between T. dubius and T. virescens adults on I. grandicollis survival was determined by placing varying numbers of each predator with a set prey number. I found a significant interaction between densities of the two predators, which indicates possible emergent predator effects. The combined effect of the predators was risk reducing for prey, likely because of intraguild predation. The predator T. dubius alone was more efficient at reducing the number of prey adults successfully entering the log. This study indicates the importance of low density releases of these predators for augmentative biological control, to reduce the effects of intraspecific competition. To determine if there were differences in pheromone preference among individual T. virescens adults, a mark-release-recapture experiment was combined in the field to provide a choice test between ipsenol and ipsdienol pheromones. Temnochila virescens adults that were initially captured on ipsenol were more frequently recaptured with this pheromone, while those first captured on ipsdienol were recaptured on both pheromones. This suggests populations of T. virescens are composed of specialists attracted only to ipsenol and generalists attracted to both ipsdienol and ipsenol pheromones.
604

AN EXPLORATION OF SKIN TONE RELATED BELIEFS AND ATTITUDES AMONG ASIAN INDIAN WOMEN IN URBAN INDIA

Ahlawat, Aditi 01 August 2017 (has links)
This study explores how changes in skin tone surveillance predicted by: (a) skin tone satisfaction, (b) preference for lighter skin tone, (c) internalization of cultural standards of attractiveness, and (d) use of skin-lightening products among Asian Indian women. Exploratory analyses with demographic variables such as age, education, and marital status were also examined. Cross-cultural issues in conducting research with Asian Indian women using U.S. American standardized measures of skin tone related variables were explored. Participants were 169 Asian Indian women over the age of 18 from New Delhi, Mumbai, and other major cities in India and proficiency in English. The data were collected via an Internet-based survey with measures including the Skin Tone Specific Surveillance Subscale of the Objectification Body Consciousness Scale (OBCS, McKinley & Hyde, 1996); the Skin Color Satisfaction Scale (SCSS, Bond & Cash, 1992); Internalization subscale from the Sociocultural Attitudes towards Appearance Questionnaire -3 (SATAQ-3, Thompson, van den Berg, Gurada, & Heinberg, 2004), and a questionnaire about skin tone preference and use of skin lightening products (Hamed, Tayyem, Nimer, & Alkhatib, 2010). Results of the study indicate that an increase in skin tone surveillance was significantly predicted by decreasing skin tone satisfaction, increased preference for lighter skin tone, internalization of cultural standards of beauty and increased use of skin lightening products among the participants. Implications of this study include illuminating the role of skin tone related attitudes and beliefs among Asian Indian women in the persistence of objectification experiences among Asian Indian women to advance feminist scholarship on objectification.
605

Teacher Preference for Response Cost and Differential Reinforcement of Alternative Behavior within Token Economies

Chalmers, Andrea Harley 01 May 2018 (has links)
Previous research on implementer preference for behavioral interventions is limited. This study empirically evaluated teachers’ preference for implementing two types of token economies in a classroom to increase on-task behavior of students. The two types of token economies were response cost and differential reinforcement of alternative behavior implemented using an interdependent group contingency. The results showed both teachers preferred response cost over differential reinforcement of alternative behavior.
606

Willingness to pay for health risk reductions: The importance of scenario adjustment, household structure and type of disease

Johnson, Erica H. 06 1900 (has links)
xii, 150 p. : ill. A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number. / Environmental regulations are increasingly subjected to benefit-cost analysis as an aid to decision-making in policy. Economic benefits are most appropriately measured by the tradeoffs of other goods and services that people are willing to make to obtain reductions in risks to their lives and health. The measure of willingness to pay ( WTP ) allows for this comparison. These benefits from risk reductions are likely to vary systematically by characteristics of the individual, including the number and ages of children present in the household, and by the type of health threat under consideration. In chapter one of this dissertation, I write a brief introduction. In the second chapter, I examine an important methodological issue--the extent of "scenario adjustment" in a Stated Preference ( SP ) conjoint choice experiment in the context of a household survey concerning health risk reductions. Scenario adjustment occurs when respondents assume that a substantive alternative in a choice set, in their own particular case, will be different than the survey instrument describes. This is a potential source of bias in SP research similar to scenario rejection, but harder to detect. I analyze the impact of scenario adjustment on WTP and suggest a possible correction. In the third chapter, I address the empirical question of patterns in adults' WTP for health risk reductions. I find that demand is influenced by the presence of children, the numbers of children in different age brackets currently in the household, and, for health risks with latency periods, by the prospect of children still being present when a parent's ill health begins or death occurs. In chapter four, I find systematic differences in WTP for health risk reductions across different types of major health threats, such as Alzheimer's disease versus heart attacks. I also look for evidence of a cancer premium due to the dread factor associated with the prospect of cancer. The health threats considered include chronic heart disease, sudden heart attacks, five types of cancers, respiratory disease, stroke, diabetes, Alzheimer's disease and traffic accidents. In chapter five, I conclude. This dissertation includes previously unpublished co-authored material. / Committee in charge: Trudy Cameron, Chairperson, Economics; William Harbaugh, Member, Economics; Robin McKnight, Member, Economics; Ronald Mitchell, Outside Member, Political Science
607

Choice difficulty and risk perceptions in environmental economics

Duquette, Eric Nigel, 1978- 09 1900 (has links)
xv, 173 p. : ill. (some col.) A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number. / Economists typically assume that individuals behave in accordance with rational choice theory. In practice, however, individual behavior can deviate from the predictions of models founded upon basic economic theory. The extent to which these deviations are important to individual decision-making in environmental economics, and thus to the development of sound environmental policies, is not fully understood. The objective in this dissertation research is to investigate potential deviations from rational choice behavior in some environmental economics contexts and to identify their relevance to environmental policy. Chapter I uses a stated-preference survey for the valuation of environmental health-risk reductions in which respondents rate the subjective difficulty of each key choice they are asked to consider. Existing literature identifies many potential categories of biases in the empirically estimated valuation of non-market goods in stated-preference research. One potential source of bias stems from the "objective complexity" of the choice scenario. I find that existing objective measures of choice set complexity do not fully explain subjective choice difficulty ratings in this valuation survey. Instead, subjective difficulty appears to result from the interplay among objective complexity, preferences, and cognitive resource constraints. In Chapter II, I consider the possible consequences of choice difficulty from the standpoint of neuroeconomics. Within the scope of neuroeconomics, one can identify some neurobiological correlates of economic decision-making activity. I study the apparent effects of choice difficulty on the neurobiological encoding of individuals' value assessments. Information from this study provides a neurological basis for deviations from simple economic theory based on conventional models of rational choice. Chapter III examines risk perceptions that may influence individuals' decisions to migrate within the U.S. to reduce potential health and economic risks related to climate change. My analysis treats historical patterns of migration among counties as a function of varying spatial and temporal patterns in tornado activity, along with other spatially and temporally delineated variables intended to capture the evolution of subjective perceptions of these tornado risks. Results suggest that the perception of risk from extreme weather events can have a small but statistically discernible effect on migration behavior across sociodemographic groups for both out-migrants and in-migrants. / Committee in charge: Trudy Cameron, Chairperson, Economics; William Harbaugh, Member, Economics; Jason Lindo, Member, Economics; Ulrich Mayr, Outside Member, Psychology
608

Essays on the Recreational Value of Avian Biodiversity

Kolstoe, Sonja 27 October 2016 (has links)
This dissertation uses a convenience sample of members of eBird, a large citizen science project maintained by the Cornell University's Laboratory of Ornithology, to explore the value of avian biodiversity to bird watchers. Panel data (i.e. longitudinal data) are highly desirable for preference estimation. Fortuitously, the diaries of birding excursions by eBird members provide a rich source of spatial data on trips taken, over time by the same individuals, to a variety of birding destinations. Origin and destination data can be combined with exogenous species prevalence information. These combined data sources permit estimation of utility-theoretic choice models that allow derivation of the marginal utilities of avian biodiversity measures as well as the marginal utility of net income (i.e. consumption of other goods and services). Ratios of these marginal utilities yield marginal willingness to pay (MWTP) estimates for numbers of bird species (or numbers of species of different types, in richer specifications). MWTP for levels of other attributes of birding destinations are also derived (e.g. ecosystem type, management regime, seasonal variations, a time trend).\\ The chapters are organized as follows: Chapter 2 is a stand-alone paper that demonstrates the feasibility of a travel-cost based random utility model with the eBird data. This chapter focuses on measuring the total number of bird species at each birding hotspot in Washington and Oregon states. This chapter does not differentiate among types of birders beyond using their recent birding activities in an analysis of habit formation or variety-seeking behavior. For this model, beyond past behavior, a representative consumer is postulated. Chapter 3 starts from the basic specifications identified in Chapter 2 and explores heterogeneous preferences among consumers as well as their preferences for species richness and for different categories of birds. This chapter explores whether different types of birds are relatively more attractive to different types of birders (for example, by gender or by age or by neighborhood characteristics and educational attainment). Chapter 4 is an extension of the work in Chapter 3 to explore how changing site attributes in the face of climate change effects birder welfare. This dissertation includes previously unpublished co-authored material. / 10000-01-01
609

Graphical preference representation under a possibilistic framework / Représentation graphique des préférences dans le cadre de la théorie de possibilités

Gouider, Héla 30 October 2017 (has links)
La modélisation structurée de préférences, fondée sur les notions d'indépendance préférentielle, a un potentiel énorme pour fournir des approches efficaces pour la représentation et le raisonnement sur les préférences des décideurs dans les applications de la vie réelle. Cette thèse soulève la question de la représentation des préférences par une structure graphique. Nous proposons une nouvelle lecture de réseaux possibilistes, que nous appelons p-pref nets, où les degrés de possibilité représentent des degrés de satisfaction. L'approche utilise des poids de possibilité non instanciés (appelés poids symboliques), pour définir les tables de préférences conditionnelles. Ces tables donnent naissance à des vecteurs de poids symboliques qui codent les préférences qui sont satisfaites et celles qui sont violées dans un contexte donné. Nous nous concentrons ensuite sur les aspects théoriques de la manipulation de ces vecteurs. En effet, la comparaison de ces vecteurs peut s'appuyer sur différentes méthodes: celles induites par la règle de chaînage basée sur le produit ou celle basée sur le minimum que sous-tend le réseau possibiliste, les raffinements du minimum le discrimin, ou leximin, ainsi que l'ordre Pareto, et le Pareto symétrique qui le raffine. Nous prouvons que la comparaison par produit correspond exactement au celle du Pareto symétrique et nous nous concentrons sur les avantages de ce dernier par rapport aux autres méthodes. En outre, nous montrons que l'ordre du produit est consistant avec celui obtenu en comparant des ensembles de préférences satisfaites des tables. L'image est complétée par la proposition des algorithmes d'optimisation et de dominance pour les p-pref nets. Dans ce travail, nous discutons divers outils graphiques pour la représentation des préférences. Nous nous focalisons en particulier sur les CP-nets car ils partagent la même structure graphique que les p-pref nets et sont basés sur la même nature de préférences. Nous prouvons que les ordres induits par les CP-nets ne peuvent pas contredire ceux des p-pref nets et nous avons fixé les contraintes nécessaires pour raffiner les ordres des p-pref nets afin de capturer les contraintes Ceteris Paribus des CP-nets. Cela indique que les CP-nets représentent potentiellement une sous-classe des p-pref nets avec des contraintes. Ensuite, nous fournissons une comparaison approfondie entre les différents modèles graphiques qualitatifs et quantitatifs, et les p-pref nets. Nous en déduisons que ces derniers peuvent être placés à mi- chemin entre les modèles qualitatifs et les modèles quantitatifs puisqu'ils ne nécessitent pas une instanciation complète des poids symboliques alors que des informations supplémentaires sur l'importance des poids peuvent être prises en compte. La dernière partie de ce travail est consacrée à l'extension du modèle proposé pour représenter les préférences de plusieurs agents. Dans un premier temps, nous proposons l'utilisation de réseaux possibilistes où les préférences sont de type tout ou rien et nous définissons le conditionnement dans le cas de distributions booléennes. Nous montrons par ailleurs que ces réseaux multi-agents ont une contrepartie logique utile pour vérifier la cohérence des agents. Nous expliquons les étapes principales pour transformer ces réseaux en format logique. Enfin, nous décrivons une extension pour représenter des préférences nuancées et fournissons des algorithmes pour les requêtes d'optimisation et de dominance. / Structured modeling of preference statements, grounded in the notions of preferential independence, has tremendous potential to provide efficient approaches for modeling and reasoning about decision maker preferences in real-life applications. This thesis raises the question of representing preferences through a graphical structure. We propose a new reading of possibilistic networks, that we call p-pref nets, where possibility weights represent satisfaction degrees. The approach uses non-instantiated possibility weights, which we call symbolic weights, to define conditional preference tables. These conditional preference tables give birth to vectors of symbolic weights that reflect the preferences that are satisfied and those that are violated in a considered situation. We then focus on the theoretical aspects of handling of these vectors. Indeed, the comparison of such vectors may rely on different orderings: the ones induced by the product-based, or the minimum based chain rule underlying the possibilistic network, the discrimin, or leximin refinements of the minimum- based ordering, as well as Pareto ordering, and the symmetric Pareto ordering that refines it. We prove that the product-based comparison corresponds exactly to symmetric Pareto and we focus on its assets compared to the other ordering methods. Besides, we show that productbased ordering is consistent with the ordering obtained by comparing sets of satisfied preference tables. The picture is then completed by the proposition of algorithms for handling optimization and dominance queries. In this work we discuss various graphical tools for preference representation. We shed light particularly on CP-nets since they share the same graphical structure as p-pref nets and are based on the same preference statements. We prove that the CP-net orderings cannot contradict those of the p-pref nets and we found suitable additional constraints to refine p-pref net orderings in order to capture Ceteris Paribus constraints of CP-nets. This indicates that CP-nets potentially represent a subclass of p-pref nets with constraints. Finally, we provide an thorough comparison between the different qualitative and quantitative graphical models and p-pref nets. We deduce that the latter can be positioned halfway between qualitative and quantitative models since they do not need a full instantiation of the symbolic weights while additional information about the relative strengths of these weights can be taken into account. The last part of this work is dedicated to extent the proposed model to represent multiple agents preferences. As a first step, we propose the use of possibilistic networks for representing all or nothing multiple agents preferences and define conditioning in the case of Boolean possibilities. These multiple agents networks have a logical counterpart helpful for checking agents consistency. We explain the main steps for transforming multiple agents networks into logical format. Finally, we outline an extension with priority levels of these networks and provide algorithms for handling optimization and dominance queries.
610

Escolha intertemporal e consumo de cigarros : recompensa imediata ou benefício futuro?

Diefenthäler, Juliana Martins January 2017 (has links)
Nos últimos anos, um grande número de estudos tem investigado o consumo de cigarros com base em uma teoria que permeia uma relação entre custos e benefícios, envolvendo trocas entre consequências em curto e longo prazo, que tem sido proposta para explicar porque escolhas insalubres – incluindo exemplos nos âmbitos de poupança, procrastinação, vício e auto-confiança – ocorrem, apesar de refletirem prejuízos. Esta abordagem, aqui definida como preferência de tempo, é um fenômeno conhecido quando os benefícios estão no presente e os custos são projetados para o futuro, permeando a teoria de tomada de decisões ao longo do tempo (escolha intertemporal) – que reflete uma escolha entre uma recompensa menor imediata e uma recompensa maior atrasada. A fim de analisar a relação de escolha entre ganhos e perdas imediatos e atrasados, em diferentes contextos, e os diversos fatores que influenciam essa escolha, um questionário foi desenvolvido a partir de artigos anteriores (Kirby, 2009; Myerson et al., 2016) e aplicado a uma amostra da população de fumantes. O objetivo das análises do presente estudo baseia-se em avaliar a influência de variáveis como domínio, gênero, idade e impulsividade em cada uma das condições do questionário, chegando a conclusões a respeito da influência das mesmas, dependendo de variáveis como contexto, tipo e efeito. Os resultados do estudo comprovam que a preferência de tempo é uma medida válida para predizer o processo de tomada de decisão de consumidores de cigarros, o que significa que fumantes são mais propensos a escolher resultados imediatos em vez de resultados atrasados. Isto indica que, de modo geral, fumantes preferem recompensas imediatas do que benefícios futuros. No entanto, os resultados do estudo apontam que, sob determinadas condições, esse efeito de preferência de tempo se reduz, aumentando a propensão de escolha por resultados atrasados em vez de resultados imediatos. Estas circunstâncias foram encontradas em diferenças relacionadas ao contexto (fumo x genérico), diferenças relacionadas ao efeito de sinal (ganho x perda), diferenças em relação aos domínios (financeiro, saúde, estético e social), diferenças a cerca do modo de comprometimento de participação (pessoal x outros) e diferenças relacionadas às características demográficas dos respondentes (faixa etária e gênero). / In the last past years, a large number of studies have investigated cigarette smoking based on a theory that permeates a relationship between costs and benefits, involving trade-offs between short and long-term consequences, which has been proposed to explain why unhealthy choices, including exemples in the areas of savings, procrastination, addiction and self-confidence - occur, even though they reflect losses. This approach, here defined as time preference, is a known phenomenon when benefits are at the present and costs are projected into the future, permeating a decision-making theory over time (intertemporal choice) - which reflect a choice between a immediate but small reward and a larger but late reward. In order to analyze these choices between immediate and delayed gains and losses in different contexts, and the various factors that influence this choice, a questionnaire was developed based on previous articles (Kirby, 2009, Myerson et al., 2016) and applied into a sample of the population of smokers. The objective of the present study is to evaluate the influence of variables such as domain, gender, age and impulsivity in each of the conditions of the questionnaire, leading to conclusions about their influence, depending on variables such as context, type and effect. The results of the study prove that time preference is a valid measure to predict the decision-making process of smokers, which means that smokers are more likely to choose immediate outcomes rather than late outcomes. This indicates that, overall, smokers prefer immediate rewards than future benefits. However, the study results point out that, under certain conditions, this time preference effect is reduced, increasing the tendency to choose for delayed results rather than immediate results. These circumstances were found in differences related to the context (smoking x generic), differences related to the sign effect (gain x loss), differences in relation to the domains (financial, health, aesthetic and social), differences about the mode of commitment of participation (personal x other) and differences related to the demographic characteristics of the respondents (age rage and gender).

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