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Behavioural asset pricing in Chinese stock marketsXu, Yihan January 2011 (has links)
This thesis addresses asset pricing in Chinese A-share stock markets using a dataset consisting of all shares listed in Shanghai and Shenzhen stock exchanges from January 1997 to December 2007. The empirical work is carried out based on two theoretical foundations: the efficient market hypothesis and behavioural finance. It examines and compares the validity of two traditional asset pricing models and two behavioural asset pricing models. The investigation is initially performed within a traditional asset pricing framework. The three-factor Fama-French model is estimated and then augmented by additional macroeconomic and bond market variables. The results suggest that these traditional asset pricing models fail to explain fully the time-variation of stock returns in Chinese stock markets, leaving non-normally distributed and heteroskedastic residuals, calling for further explanatory variables and suggesting the existence of a structure break. Indeed, the macroeconomic and bond market factors provide little help to the asset pricing model. Using the Fama-French model as the benchmark, further research is done by investigating investor sentiment as the third dimension beside returns and risks. Investor sentiment helps explain the mis-pricing component of returns in the Fama-French model and the time-variation in the factors themselves. Incorporating investor sentiment into the asset pricing model improves the model performance, lessening the importance of the Fama-French factors, and suggesting that in China, sentiment affects both the way in which investors judge risks as well as portfolio returns directly. The sentiment effect on asset pricing is also examined under a nonlinear Markov-switching framework. The stochastic regime-dependent model reveals that stock returns in China are driven by fundamental factors in bear and low volatility markets but are prone to sentiment and become uncoupled from fundamental risks in bull and high volatility markets.
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The Operation and Administration of Elementary School Arts Association:Kaohsiung Municipal Yen-Chen Primary School As An ExampleTAI, Hui-mei 18 October 2004 (has links)
Participating students¡¦ association at school can enhance the students¡¦ learning, all kinds of life skills and social abilities. It¡¦s not simply a part of curriculum courses, but with more significance on cultivating the concept of being gregarious and law-abiding. Arising out of this, it comprehends positively the purpose of being well-developed education.
The subject of this thesis is ¡§the Operation and Administration on the Student Arts Association at Elementary Schools¡¨, enphasizing mainly on the influences on students who have already participated the arts asssociation. From my observation on the anterior research, they emphasized more on the study of music asssociation as well as pedagogy, instead of expanding thoroughly on the operation and administration on arts asssociation.
This thesis takes seven arts organizations as case studies, they separately are: Orchestra, Choir, Taiwanese Golden Loin Dance, Jazz Dance Group, Arts Association, Recorder Association, and Pottery-flute Association. The purposes of this research are, firstly, make a thorough investigation on the operation mode of the Elementary Schools¡¦ Arts Association, by the theory and method of management; secondly, in order to comprehend the operation mode of Yen-Chen Elementary School¡¦s Arts association, the interviews of each individual case are applied. Also, the interview groups can be divided into five: administrants, professors, students, graduated students, and parents of students, to the amount of twenty-two cases.
This thesis draws two main conclusions.One is the suggestions for operation and administration:(1)arts association demand clearer objectives;(2)they require stronger organization;(3)they call for a flexible staff;(4)they need concise plans which should be excuted with good use of resourses;(5)with the ideas of ¡¥positive aspiration¡¦ and ¡¥encouragement leadership¡¦, arts associations aim to converge comradship;(6)arts association are supposed to recruit new members and hold the old ones;(7)The mainipulation of funds should be made public;(8)Relations among arts associations should be intensified.
The other part suggests that students not only learn professions, but also cultivate appreciation. Students make friends, develop abilities and have a good time in clubs. Therefore, most of students join the same association when they go to high schools.
This thesis is devided into five chapters. Chapter One is the introduction about research background and theme; Chapter Two is the literature review and theory framework; Chapter Three is the method; Chapter Four is the research process; Chapter Five is the conclusion and suggestions.
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Impact of Product Market Competition on Expected ReturnsLiu, Chung-Shin 12 1900 (has links)
x, 94 p. : ill. (some col.) / This paper examines how competition faced by firms affects asset risk and expected returns. Contrary to Hou and Robinson's (2006) findings, I find that cross-industry variation in competition, as measured by the concentration ratio, is not a robust determinant of unconditional expected stock returns. In contrast, within-industry competition, as measured by relative price markup, is positively related to expected stock returns. Moreover, this relation is not captured by commonly used models of expected returns. When using the Markov regime-switching model advocated by Perez-Quiros and Timmermann (2000), I test and find support for Aguerrevere's (2009) recent model of competition find risk dynamics. In particular, systematic risk is greater in more competitive industries during bad times and greater in more concentrated industries during good times. In addition, real investment by firms facing greater competition leads real investment by firms facing less competition, supporting Aguerrevere's notion that less competition results in higher growth options and hence higher risk in good times. / Committee in charge: Dr. Roberto Gutierrez, Chair;
Dr. Roberto Gutierrez, Advisor;
Dr. Diane Del Guercio, Inside Member;
Dr. John Chalmers, Inside Member;
Dr. Bruce Blonigen, Outside Member
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Marginally Interpretable Generalized Linear Mixed ModelsGory, Jeffrey J. 26 October 2017 (has links)
No description available.
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Essays on Consumption-based Asset Pricing ModelsBin Li Unknown Date (has links)
Consumption-based asset pricing models (CCAPMs) connect asset returns with consumption growth. The poor empirical performance of early consumption models has led to the development of a number of more sophisticated models. Nevertheless, most models focus on the US markets, and very few CCAPMs have been examined in the Australian context. Given the importance of CCAPMs, the purpose of this thesis is to examine the connections between asset returns in the Australian market and consumption variables. The thesis also extends the analysis to examine CCAPMs in an international setting. There are four essays in this thesis. The first essay undertakes a thorough investigation of the empirical support for consumption-based asset pricing models in the context of several major Australian asset classes. Using the generalised method of moments (GMM) econometric approach, my study begins with the classic CCAPM originally tested by Hansen and Singleton (1982, 1983). The empirical analysis is then extended to test more-recent specifications of the CCAPM, including the habit-formation models of Abel (1990) and Campbell and Cochrane (2000), and the time nonseparable model of Epstein and Zin (1991). For each of the models examined, the results provide cautious support for the CCAPM especially in relation to equity returns. Size-sorted portfolios (in particular, portfolios of small stocks) and fixed-income returns cause the CCAPM restriction to be rejected. It also presents results that raise questions over the benefits from extensions of the classic CCAPM, such as habit-persistence and recursive utility models. The second essay studies the empirical performance of a linearised version of the classic CCAPM in the Australian market. The studies of Faff and Oliver (1998) and Faff (1998) are extended by employing more recent data and examining 25 size/BM portfolios as well as industry portfolios. It is found that by using the lagged portfolio returns, the linearised CCAPM for both industry portfolios and 25 size/BM portfolios is generally not rejected. The third essay empirically examines conditional CCAPMs where the conditioning variables are consumption factors such as the consumption-wealth ratio proposed by Lettau and Ludvigson (2001a, 2001b), the surplus consumption ratio (Campbell and Cochrane, 1999), and the labour income to consumption ratio (Santos and Veronesi, 2006). Here long-horizon return predictability tests are conducted using these factors and cross-sectional tests on whether these factors are priced using both 25 Size/BM portfolios and industry portfolios. Utilising the Fama-MacBeth (1973) procedure, it is found that conditional models perform better than unconditional models. However, these conditional models do not outperform the Fama-French three-factor model. The fourth essay tests the world CCAPMs. Using data for 17 countries, the following are tested: the classic world CCAPM under the assumption of complete international markets integration, the heterogeneous world CCAPM under the framework of Constantinides and Duffie (1996) and the world habit models. The finding here is that a large risk aversion is needed to resolve the equity premium puzzle for the classic world CCAPM; however, adding a cross-country consumption dispersion factor into the model significantly lowers the coefficients of consumption risk aversion. Unconditional linear factor models are also studied where it is found that the world consumption growth and the dispersion of the cross-sectional consumption growth provide some explanatory basis for the variation in the cross section of excess stock returns. More sophisticated consumption models perform better than the classic world CCAPM. This thesis makes a worthwhile contribution to the research literature on CCAPMs in Australia which up to now has been limited. It performs out-of-sample tests of major CCAPMs utilising several Australian asset classes. It not only provides some insights into the return predictability of the aggregate market index in Australia, but also presents some evidence of the explanation of the cross section of stock returns using consumption variables. Further, this thesis adds to the understanding of the
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Modèles d'appariement du greffon à son hôte, gestion de file d'attente et évaluation du bénéfice de survie en transplantation hépatique à partir de la base nationale de l'Agence de la Biomédecine. / Liver transplantation graft-to-recipient matching models, queue management and evaluation of the survival benefit : study based on the Agency of Biomedicine national databaseWinter, Audrey 28 September 2017 (has links)
La transplantation hépatique (TH) est la seule intervention possible en cas de défaillance hépatique terminale. Une des limitations majeures à la TH est la pénurie d'organes. Pour pallier ce problème, les critères de sélection des donneurs ont été élargis avec l'utilisation de foie de donneurs dits à "critères étendus" (extended criteria donor (ECD)). Cependant, il n'existe pas de définition univoque de ces foies ECD. Un score donneur américain a donc été mis en place : le Donor Risk Index (DRI), pour qualifier ces greffons. Mais à qui doit-on donner ces greffons "limites"? En effet, une utilisation appropriée des greffons ECD pourrait réduire la pénurie d'organes. Le but de cette thèse est d'établir un nouveau système d'allocation des greffons qui permettrait à chaque greffon d'être transplanté au candidat dont la transplantation permettra le plus grand bénéfice de survie et d'évaluer l'appariement entre donneurs et receveurs en tenant compte des greffons ECD.La première étape a consisté à effectuer une validation externe du DRI ainsi que du score qui en découle : l'Eurotransplant-DRI. Toutefois la calibration et la discrimination n'étaient pas maintenus dans la base française. Un nouveau score pronostique donneur a donc été élaboré : le DRI-Optimatch, à l'aide d'un modèle de Cox donneur ajusté sur les covariables receveur. Le modèle a été validé par bootstrap avec correction de la performance par l'optimisme.La seconde étape consista à explorer l'appariement entre donneur et receveur afin d'attribuer les greffons ECD de manière optimale. Il a été tenu compte des critères donneurs et receveurs, tels qu'évalués par le DRI-Optimatch et par le MELD (Model for End-stage Liver Disease, score pronostique receveur), respectivement. La méthode de stratification séquentielle retenue s'inspire du principe de l'essai contrôlé randomisé. Nous avons alors estimé, à l'aide de rapport de risques, quel bénéfice de survie un patient donné (repéré à l'aide du MELD) pourrait avoir avec un greffon donné (repéré à l'aide du DRI-Optimatch) en le comparant avec le groupe de référence composé des patients (même MELD), éligibles à la greffe, restés sur liste dans l'attente d'un meilleur greffon (DRI-Optimatch plus petit).Dans une troisième étape, nous avons développé un système d'allocation basé sur le bénéfice de survie alliant deux grands principes dans l'allocation de greffons; l'urgence et l'utilité. Dans ce type de système, un greffon alloué est attribué au patient avec la plus grande différence entre la durée de vie post-transplantation prédite et la durée estimée sur la liste d'attente pour un donneur spécifique. Ce modèle est principalement basé sur deux modèles de Cox : un pré-greffe et un post-greffe. Dans ces deux modèles l'évènement d'intérêt étant le décès du patient, pour le modèle pré-greffe, la censure dépendante a été prise en compte. En effet, sur liste d'attente le décès est bien souvent censuré par un autre évènement : la transplantation. Une méthode dérivée de l'Inverse Probability of Censoring Weighting a été utilisée pour pondérer chaque observation. De plus, données longitudinales et données de survie ont aussi été utilisées. Un modèle "en partie conditionnel", permettant d'estimer l'effet de covariables dépendantes du temps en présence de censure dépendante, a été utilisé pour modéliser la survie pré-greffe.Après avoir développé un nouveau système d'allocation, la quatrième et dernière étape, nous a permis de l'évaluer à travers de simulation d'évènement discret ou DES : Discret Event Simulation. / Liver transplantation (LT) is the only life-saving procedure for liver failure. One of the major impediments to LT is the shortage of organs. To decrease organ shortage, donor selection criteria were expanded with the use of extended criteria donor (ECD). However, an unequivocal definition of these ECD livers was not available. To address this issue, an American Donor Risk Index (DRI) was developed to qualify those grafts. But to whom should those ECD grafts be given? Indeed, a proper use of ECD grafts could reduce organ shortage. The aim of this thesis is to establish a new graft allocation system which would allow each graft to be transplanted in the candidate whose LT will allow the greatest survival benefit; and to evaluate the matching between donors and recipients taking into account ECD grafts.The first step was the external validation of the DRI as well as the resultant Eurotransplant-DRI score. However, calibration and discrimination were not maintained on the French database. A new prognostic donor score: the DRI-Optimatch was then developed using a Cox donor model with adjustment on recipient covariates. The model was validated by bootstrapping with correction of the performance by the optimism.The second step was to explore the matching between donors and recipients in order to allocate ECD grafts optimally. Consideration should be given to the donor and recipient criteria, as assessed by the DRI-Optimatch and the Model for End-stage Liver Disease (MELD), respectively. The sequential stratification method retained is based on the randomized controlled trial principle. We then estimated, through hazard ratios, the survival benefit for different categories of MELD and DRI-Optimatch compared against the group of candidates remaining on the wait list (WL) and waiting for a transplant with a graft of better quality (lower DRI-Optimatch).In the third step, we have developed an allocation system based on survival benefit combining the two main principles in graft allocation; urgency and utility. In this system, a graft is allocated to the patient with the greatest difference between the predicted post-transplant life and the estimated waiting time for a specific donor. This model is mainly based on two Cox models: pre-LT and post-LT. In these two models the event of interest being the death of the patient, for the pre-graft model, the dependent censoring was taken into account. Indeed, on the WL, death is often censored by another event: transplantation. A method derived from Inverse Probability of Censoring Weighting was used to weight each observation. In addition, longitudinal data and survival data were also used. A partly conditional model, to estimate the effect of time-dependent covariates in the presence of dependent censoring, was therefore used for the pre-LT model.After developing a new allocation system, the fourth and final step was to evaluate it through Discrete Event Simulation (DES).
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Reversing Cancer Cell Fate: Driving Therapeutic Differentiation of Hepatoblastoma to Functional Hepatocyte-Like CellsSmith, Jordan L. 20 March 2020 (has links)
Background & Aims: Despite advances in surgical care and chemotherapeutic regimens, the five-year survival rate for Stage IV Hepatoblastoma (HB), the predominant pediatric liver tumor, remains at 27%. YAP1 and β-Catenin co-activation occurs in 80% of children’s HB; however, a lack of conditional genetic models precludes exploration of tumor maintenance and therapeutic targets. Thus, the clinical need for a targeted therapy remains unmet. Given the predominance of YAP1 and β-catenin activation in children’s tumors, I sought to evaluate YAP1 as a therapeutic target in HB.
Approach & Results: Herein, I engineered the first conditional murine model of HB using hydrodynamic injection to deliver transposon plasmids encoding inducible YAP1S127A, constitutive β-CateninDelN90, and a luciferase reporter to murine liver. Tumor regression was evaluated using in vivo bioluminescent imaging, and tumor landscape characterized using RNA sequencing, ATAC sequencing and DNA foot-printing. Here I show that YAP1 withdrawal in mice mediates >90% tumor regression with survival for 230+ days. Mechanistically, YAP1 withdrawal promotes apoptosis in a subset of tumor cells and in remaining cells induces a cell fate switch driving therapeutic differentiation of HB tumors into Ki-67 negative “hbHep cells.” hbHep cells have hepatocyte-like morphology and partially restored mature hepatocyte gene expression. YAP1 withdrawal drives formation of hbHeps by modulating liver differentiation transcription factor (TF) occupancy. Indeed, tumor-derived hbHeps, consistent with their reprogrammed transcriptional landscape, regain partial hepatocyte function and can rescue liver damage in mice.
Conclusions: YAP1 withdrawal, without modulation of oncogenic β-Catenin, significantly regresses hepatoblastoma, providing the first in vivo data to support YAP1 as a therapeutic target for HB. Modulating YAP1 expression alone is sufficient to drive long-term regression in hepatoblastoma because it promotes cell death in a subset of tumor cells and modulates transcription factor occupancy to reverse the fate of residual tumor cells to mimic functional hepatocytes.
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