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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.
151

Ambiguity and the Incentive to Export

Broll, Udo, Wong, Kit Pong 11 September 2014 (has links) (PDF)
This paper examines the optimal production and export decisions of an international firm facing exchange rate uncertainty when the firm's preferences exhibit smooth ambiguity aversion. Ambiguity is modeled by a second-order probability distribution that captures the firm's uncertainty about which of the subjective beliefs govern the exchange rate risk. Ambiguity preferences are modeled by the (second-order) expectation of a concave transformation of the (first-order) expected utility of profit conditional on each plausible subjective distribution of the exchange rate risk. Within this framework, we show that ambiguity has no impact on the firm's propensity to export to a foreign country. Ambiguity and ambiguity aversion, however, are shown to have adverse effect on the firm's incentive to export to the foreign country.
152

Värdering av prestation och riskbeteende i ung ålder : Finns det ett samband? / Estimation of perfomance and risk behavior in young age : Is there a correlation?

Gårdbro, Erik January 2015 (has links)
This paper is a study how students at a high school in Falun, Sweden, estimates their performance in an upcoming math test which is then compared with the actual grade the student performed. The students who participated also answered questions related to “risk situations” to examine whether there is a correlation between how students estimate their performance in the context and their risk behavior, and if the students act like economic models assume. In agreement with previous studies, the boys in the survey tended to be overconfident in their performance. The girls in the study were neither over- nor underconfident in her performance and no significant difference in the estimation of one's performance between the sexes could be proven. The proportion of boys who considered themselves to take greater risk than class average was greater than the proportion of girls in the question. No linear relationship between estimation of performance and risk behavior or differences in risk behavior could be found between the sexes.
153

Differential Protein Expression in the Insular Cortex and the Amygdala after Taste Memory Acquisition and Retrieval

Venkataraman, Archana 03 October 2013 (has links)
Long-term memories turn labile with reactivation and undergo a re-stabilization process, termed reconsolidation, involving molecular changes that allow updating of an existing memory trace. Such molecular changes may involve the activation of kinases and expression of proteins related to the increase of synaptic plasticity and memory formation. A kinase reported to have a role in a variety of memory tasks is the extracellular signal-regulated kinase 1/2 (ERK1/2). The downstream activation of ERK targets other regulatory enzymes, transcription factors and cytoskeletal proteins, which allow structural changes in the neuron due to protein synthesis up-regulation. Among the proteins up-regulated by ERK activity is the activity-regulated cytoskeleton-associated protein (ARC), an immediate early gene related to synaptic plasticity. The phase-dependent roles of ERK and ARC have not been examined as part of the molecular mechanisms triggered after a learning experience. In this study I used conditioned taste aversion (CTA) as the learning paradigm and investigated the expression of pERK and ARC in brain regions critical for taste information processing such as the insular cortex and the amygdala. A differential pattern of protein expression was observed in the insular cortex (IC) two hours after taste memory acquisition: pERK activity increased in the aversively conditioned group while ARC increased in the group that received only the novel taste. The central amygdala (CeA) showed a significant increase in pERK, but not ARC activity after CTA training. Immunoblotting experiments performed after memory retrieval in the appetitive group show that pERK continues to signal aversive taste to the IC with ARC exhibiting heightened expression an hour later. An increase in ARC expression 30 minutes after reactivation of the aversive taste was seen in the basolateral amygdala and the CeA exhibited a similar increase at 60 and 90 minutes. Local infusion of ARC antisense oligonucleotides within the IC interfered with the consolidation of safe taste memories, but not with their acquisition. Trace update experiments showed that ARC influences the memory switch from aversive to safe, but not the reverse. Our results indicate that ARC plays a critical role in consolidation and updating of safe taste memories, and the ARC signaling could possibly elicit ERK activation.
154

Applications of learning theory to human-bear conflict: the efficacy of aversive conditioning and conditioned taste aversion

Homstol, Lori 06 1900 (has links)
I tested the efficacy of aversive conditioning (AC) and conditioned taste aversion (CTA) on American black bears (Ursus americanus) in Whistler, British Columbia. Black bears subjected to 3-5 day AC programs responded by increasing their wariness toward humans, while control bears habituated. Bears were located closer to human developments during daylight hours after AC treatments. However, there was no difference in the proportion of utilization distribution that overlapped with developed areas in control or AC-treated bears. CTA may be effective for managing specific attractants that are difficult to secure from bears. Bears appeared to distinguish between baits treated with thiabendazole and baits that were not treated, but by using a protocol that caused severe illness and left the source of illness in doubt, I induced taste aversions to apples in 4 bears. Using both AC and CTA may help wildlife managers mitigate human-wildlife conflicts non-lethally more effectively. / Ecology
155

Brain maturation in chickens: Biochemical, behavioural and electrophysiological investigations

Atkinson, Rebbekah Josephine January 2007 (has links)
Research Doctorate - Doctor of Philosophy (PhD) / This thesis investigates mechanisms of brain maturation by utilising the special advantages offered by the protracted maturation of neural circuits in chicken forebrain. Biochemical, behavioural and electrophysiological techniques are used in behaving animals to investigate the functional consequences of maturation changes at the molecular, behavioural and physiological levels. Two issues are addressed: (1) do immature (2 week) and mature (8 week) chickens employ different molecular mechanisms to produce changes in neuronal function after learning a behavioural task; and (2) can quantitative non-invasive measures of neuronal function be used to monitor maturation changes in chicken forebrain? Biochemical investigation of subcellular fractions using antibodies and western blots of chicken forebrain and intermediate medial mesopallium (IMM) revealed regional differences in expression levels of a number of components of the glutamatergic neurotransmitter system. The discriminative taste aversion learning (DTAL) task was used to assess whether an animal learns the same task at different ages using different intracellular signalling pathways. The patterns of biochemical change seen in the IMM after DTAL training was very different at 2 weeks and 8 weeks. Two major differences were observed. Firstly, the same type of training induced changes occurred at both ages in GluR1 and CaMKII but they occurred faster at 8 weeks. Secondly the difference in ERK and CREB responses is consistent with a change in the relative contribution made by the ERK signalling pathway and CREB requirement to learning at these two ages. These results imply that the molecular changes induced by learning a behavioural task are faster in mature than immature brain and may involve a different balance of intracellular signalling pathways. In order to be able to investigate biological mechanisms controlling maturation and to use the chicken as an animal model in which pharmacological and/or environmental agents can be screened for potentially harmful effects on brain maturation two non-invasive measures of neuronal function were investigated. One was behavioural (prepulse inhibition: PPI) and the other was electrophysiological (auditory evoked related potentials: AERP). PPI in the chicken was examined electromyographically and via whole body movement with a stabilimeter apparatus. In two strains of chicken (a meat breed and a laying breed) PPI was identified but shown to be small and variable compared to that in the rat. The results indicate that the phenomenon of PPI in the chicken is too small and variable to be used as a quantitative measure of neural circuit maturation. Quantitative analysis of the chicken AERP revealed a significant decrease in amplitude of the positive AERP component and a decrease in latency of the negative AERP component with maturation. These maturation changes were comparable to developmental changes seen in human and other mammal AERPs. Such changes may reflect changes in the intracortical synaptic organisation of the auditory cortex. This technique allowed for repeated measures to be undertaken on the same animal over a number of weeks and enabled developmental changes to be monitored. This technique was extended to investigate perturbed maturation via the induction of chemically induced hypothyroidism. Results from this study showed that the induction of late onset hypothyroidism produces measurable effects on the chicken AERP consistent with perturbation in maturation of neuronal circuits and synapses. This suggests that AERPs may be useful non-invasive functional measures of brain maturation that can be used to study the effects of endogenous or exogenous factors on brain maturation in the chicken. Since human brain also exhibits a protracted maturation period the availability of a well characterised animal model for protracted brain maturation provides an opportunity to identify molecules, genes and environmental factors that are important in the regulation of maturation. Such a model may provide the basis for developing rational therapies or prevention strategies for some neurodevelopmental disorders. The protracted maturation of neuronal circuits observed in chicken forebrain offers such a model.
156

Local futures traders and behavioural biases evidence from Australia /

Grant, Joel. January 2007 (has links)
Thesis (Ph.D.)--University of Wollongong, 2007. / Typescript. Includes bibliographical references: leaf 168-189.
157

"Hitting below the belt" : moral and legal barriers to the pursuit of risk-free conflict /

Trsek, Robert B. January 2008 (has links)
Thesis (M.S.)--School of Advanced Air and Space Studies, 2008. / "June 2008." Vita. Includes bibliographical references (p. 82-84). Also available via the Internet.
158

Essays in asset pricing

Liu, Liu January 2017 (has links)
This thesis improves our understanding of asset prices and returns as it documents a regime shift risk premium in currencies, corrects the estimation bias in the term premium of bond yields, and shows the impact of ambiguity aversion towards parameter uncertainty on equities. The thesis consists of three essays. The first essay "The Yen Risk Premiums: A Story of Regime Shifts in Bond Markets" documents a new monetary mechanism, namely the shift of monetary policies, to account for the forward premium puzzle in the USD-JPY currency pair. The shift of monetary policy regimes is modelled by a regime switching dynamic term structure model where the risk of regime shifts is priced. Our model estimation characterises two policy regimes in the Japanese bond market---a conventional monetary policy regime and an unconventional policy regime of quantitative easing. Using foreign exchange data from 1985 to 2009, we find that the shift of monetary policies generates currency risk: the yen excess return is predicted by the Japanese regime shift premium, and the emergence of the yen carry trade in the mid 1990s is associated with the transition from the conventional to the unconventional monetary policy in Japan. The second essay "Correcting Estimation Bias in Regime Switching Dynamic Term Structure Models" examines the small sample bias in the estimation of a regime switching dynamic term structure model. Using US data from 1971 to 2009, we document two regimes driven by the conditional volatility of bond yields and risk factors. In both regimes, the process of bond yields is highly persistent, which is the source of estimation bias when the sample size is small. After bias correction, the inference about expectations of future policy rates and long-maturity term premia changes dramatically in two high-volatility episodes: the 1979--1982 monetary experiment and the recent financial crisis. Empirical findings are supported by Monte Carlo simulation, which shows that correcting small sample bias leads to more accurate inference about expectations of future policy rates and term premia compared to before bias correction. The third essay "Learning about the Persistence of Recessions under Ambiguity Aversion" incorporates ambiguity aversion into the process of parameter learning and assess the asset pricing implications of the model. Ambiguity is characterised by the unknown parameter that governs the persistence of recessions, and the representative investor learns about this parameter while being ambiguity averse towards parameter uncertainty. We examine model-implied conditional moments and simulated moments of asset prices and returns, and document an uncertainty effect that characterises the difference between learning under ambiguity aversion and learning under standard recursive utility. This uncertainty effect is asymmetric across economic expansions and recessions, and this asymmetry generates in simulation a sharp increase in the equity premium at the onset of recessions, as in the recent financial crisis.
159

Essays on Decision Making under Stress / Essays on Decision Making under Stress

Cingl, Lubomír January 2016 (has links)
Název / Title Eseje o rozhodování pod stresem / Essays on Decision Making under Stress Student PhDr. Lubomír Cingl Studijní program / Study program Ekonomické teorie Školitel / Advisor PhDr. Michal Bauer, Ph.D. Abstract This dissertation comprises three thematically connected experimental studies of human behavior under non- standard conditions: time-pressure and stress. In the Introduction section I present the argument for why it is important for economists to recognize stress research as a valid part of the research in economics and how it can contribute to the growing knowledge of human behavior in general, including several examples from the literature. The first paper presented in Chapter 2 examines the effect of time pressure on the individual propensity to herd, while the remaining two papers examine the effect of acute stress on risk-preferences and herding behavior, respectively. Herding behavior is a very important phenomenon in human decision making since social influence is very frequent in our lives and economic decisions: consider traders in financial markets, wait-and-see investors, but also purchase behavior due to fads, fashion and top-ten lists. Risk preferences are another essential factor which determines many important economic outcomes, and the assumption of their stability is a...
160

Anxiety-Relief Conditioning: An Empirical Investigation

LeTendre, Dana 08 1900 (has links)
The current study investigated the efficacy of Wolpe's original (1954) paradigm of anxiety-relief conditioning. The procedure consisted of administering a mildly aversive electric shock to a subject for several seconds until the subject said the word "Relax," and the shock was terminated. Repeated pairings were claimed by Wolpe to condition physiological relief to the cue word, "Relax," which could then be employed in order to reduce anxiety in various anxiety provoking situations. Since there does not appear to be a generally accepted theoretical rationale to account for the reported efficacy of anxiety-relief conditioning, several theoretical rationales were discussed. In addition, a distinction was made between the anxiety-relief paradigm described by Wolpe (1954) and the aversion-relief paradigm employed by subsequent investigators (Gaupp, Stern, & Galbraith, 1972; Solyom, McClure, Heseltine, Ledwidge, & Solyom, 1972; Thorpe, Schmidt, Brown, & Castell, 1964). It was suggested that this distinction might be used to account for the failure of the current investigation to support the efficacy of anxiety-relief conditioning, as a review of the major study supporting its efficacy (Turnage & Wenrich, 1974) indicated that aversion-relief, rather than anxiety-relief, may have been employed. In the absence of strong supportive evidence for the efficacy of Wolpe's anxiety-relief paradigm, the need for further research elucidating the relevant parameters was discussed, and specific areas requiring more intensive study were delineated.

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