• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 7047
  • 1938
  • 732
  • 597
  • 595
  • 518
  • 134
  • 121
  • 114
  • 103
  • 97
  • 93
  • 85
  • 83
  • 68
  • Tagged with
  • 14755
  • 9119
  • 1970
  • 1798
  • 1637
  • 1544
  • 1301
  • 1234
  • 1231
  • 1219
  • 1053
  • 1012
  • 998
  • 957
  • 875
  • 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.
451

Essays on real options and strategic behaviour

Lambrecht, Bart Maria Andreas Corneel January 1996 (has links)
In the past decade a lot of attention has been devoted to the option valuation approach to i~vestments in financial economics. This theory provides a fl exible way of incorporating uncertainty and irreversibility into the making of the investment decision. The primary purpose of this study is to extend the contingent claim approach by introducing a strategic dimension into the investment decision. In particular we focus on the case where an investor may be preempted by one or more competitors, and where there is an advantage of acting first. Secondly, we apply the strategic options approach to some important areas in financial economics, such as corporate investment under uncertainty, corporate default , market micro-structure . and the timing of arbitrage. Apart from illustrating the wide applicability and relevance of the techniques, this also clarifies some important issues in financial economics. 'Option Games' (jointly written with William Perraudin) describes a way of incorporating strategic behaviour and asymmetric information into optimal stopping decisions under uncertainty. vVe derive optimal stopping rules when each agent's payoff is affected by the actions of other agents and these latter are of unknown type. 'Strategic Sequential Investments: an Application to Preemptive Patenting' derives the optimal investment rules for an incumbent and a challenger who both have an option to patent an innovation with stochastic payoff. We find that the optimal trigger rule is determined by a trade-off between the benefit of waiting to invest and the need to act quickly due to the competitive threat. In particular, we demonstrate that both the strategic Marshallian break-even investment trigger and the trigger obtained by the option valuation approach are in fact limit_ing polar cases of the strategic investment trigger developed in this paper. We then extend the model to a two-stage sequential investment situation where the first and the second stage respectively consist of patenting and launching the product. The model allows us to explain and analyse the phenomenon of sleeping patents. It appears that sleeping patents are more likely to occur when interest rates are low, price volatility is high or when the first stage_ cost is small relative to the second stage cost. 'Creditor Races and Contingent Claims' (jointly written with William Perraudin) presents a simple pricing model in which two debt-holders with incomplete information about each other's type decide when to foreclose on a financially-distressed firm. 'The Timing of Arbitrage: an Options Approach' presents a continuous-time modei for the timing of riskless arbitrage when the mispricing between two equivalent portfolios varies stochastically through time under the exogenous impact of liquidity trades and when there is a persistent prospect that the arbitrage bubble can 'burst'. The model endows the arbitrageur with n options to do arbitrage. When endogenously determined arbitrage bounds a re violated one or more arbitrage trades bring asset prices back within the bounds. The model is extended to the case where there are two competing arbitrageurs who have incomplete information about each other's type.
452

The Development of a Patient Decision Aid for Patients with Rectal Cancer

Scheer, Adena Sarah January 2011 (has links)
Context: Rectal cancer treatment decisions involve tradeoffs between outcomes like living with a permanent stoma versus long-term bowel dysfunction. The needs of rectal cancer patients and practitioners to partake in shared decision making are unknown. For such a complex decision, a patient decision aid that prepares patients to make informed, values-based decisions is warranted. Methods: 1) A systematic review, to characterize the prevalence of long-term dysfunction 2) Needs assessments, conducted with rectal cancer patients and practitioners, 3) Development of a decision aid. Results: 1) Significant variability exists in reporting rectal cancer outcomes. The rate of bowel dysfunction is high. 2) Rectal cancer patients recall little of the outcomes discussed preoperatively. They do not perceive having any surgical options. Practitioners are inconsistently engaging patients in shared decision-making. 3) A patient decision aid was developed that a) incorporated systematic review results and; b) addressed the needs, barriers and facilitators raised. Conclusions: Shared decision-making in rectal cancer surgery is limited. A decision aid to improve patient decision-making was developed.
453

Evaluation of a Rectal Cancer Patient Decision Aid and the Factors Influencing its Implementability in Clinical Practice

Wu, Robert January 2015 (has links)
A rectal cancer patient decision aid (PtDA) was developed to help patients consider the benefits and risks associated with two surgical treatment options. The current thesis evaluated the effect of the PtDA on patients and explored surgeons’ perceived factors influencing the implementation of the PtDA in clinical practice. Using a before and after study design, the PtDA was given to patients with rectal cancer at a cancer assessment center. Based on 28 patients recruited, the PtDA improved their knowledge, lowered decisional conflict, and patients rated it acceptable. A cross-sectional survey was mailed to 105 Canadian colorectal surgeons and 49 responded (46.7% response rate). Commonly perceived barriers were time constraint, need for multiple visits, and additional personnel and facilitators were simplifying the decision aid, adding to content, and translating to other languages. The PtDA improved patient decision making outcomes but requires interventions to overcome surgeon-identified barriers to use in clinical practice.
454

The effect of anxiety and defensiveness on testing expectation theories of decision making

Wilson, William Taylor January 1965 (has links)
The general purpose of this study was to examine one approach to the study of the relationship of personality variables to expectation theories of gambling. The Coombs and Bezembinder (1964) method of testing expectation theories of gambling behaviour was used to determine how many, among a group of 77 subjects, obeyed each of four expectation theories. These four expectation theories were: EV theory, assuming the maximization of the product of objective prize values and actual probabilities of winning; EU theory, assuming maximization of the product of subjective prize values and actual probabilities of winning; SEV theory, assuming the maximization of the product of objective prize values and subjective probabilities of winning; and SEU theory, assuming the maximization of the product of subjective value of the prize and the subjective probability of winning. The Coombs and Bezembinder method consists of comparing an estimate of an individual's consistency of choices independent of expectation theory assumptions with estimates of consistency under assumptions basic to each of the four expectation theories. A lower value of the consistency estimate under assumptions of a given expectation theory than the value calculated independently of any expectation theory assumptions leads to rejection of that particular theory as a model for the subject's behavior. The Coombs and Bezembinder technique for determining whether an individual obeys the four expectation theories leads to the prediction of an ordering of the expectation theories with respect to the number of subjects who do not satisfy them. The procedure in the present study involved the presentation of 96 pairs of one-outcome gambles to 77 subjects in an introductory psychology class. A subject was required on each pair to choose between a gamble combining high risk with a large prize and a gamble combining a low risk with a small prize. It was found that EV theory was rejected for 57 subjects, EU theory for 31 subjects, SEV theory for 26 subjects and SEU theory for 14 subjects. The hypothesis of monotonicity in the number of rejections for the two sequences SEU-SEV-EV and SEU-EU-EV was accepted. A second hypothesis, that a higher proportion of females will obey the expectation theories than will males, was rejected. The subjects were subdivided into high and low anxious and high and low defensive groups groups on the basis of scores obtained on the Alpert and Haber Test Anxiety Scale and the Crowne and Marlowe Defensiveness Scale. An examination of the data was sufficient to reject the hypothesis that more low anxious-low defensive and high anxious-high defensive subjects would obey the four expectation theories than would subjects who were either low anxious-high defensive or high anxious-low defensive. There were, however, some statistically significant results obtained on the basis of several ad hoc analyses. Fewer high defensive males than low defensive males appeared to obey SEV theory. Furthermore, fewer males who were either high anxious-high defensive or low anxious-low defensive obeyed SEU and SEV theory than did males who were either low anxious-high defensive or high anxious-low defensive. On the basis of these results, it was recommended that further research be conducted on the relationships of personality variables to expectation theories of gambling. It was noted that the use of the Tversky method of testing expectation theories would permit the simultaneous examination of two approaches to the relationship of personality variables to decision making (personality variables versus propensity for risk and personality variables versus rationality of decision). Finally, with respect to technique, it was recommended that better ways of assessing personality variables be found and the subjects be fully trained and run individually through the experiment. / Arts, Faculty of / Psychology, Department of / Graduate
455

Teaching from the student's point-of-view : a developmental perspective

Levitt, Lori Nadine January 1988 (has links)
This study was an exploratory study of how teachers, when faced with classroom problems which are ill-defined problems, identify and interpret the student's point-of-view. The extent to which the concept of "teacher as problem finder" may describe those teachers who have the structures and strategies necessary for teaching from a developmental perspective was also examined. The non-random sample consisted of 27 primary and intermediate level teachers who participated in district-sponsored in-service courses designed to introduce them to a developmental perspective on education. Participants were asked to complete 'The Student Anecdotes Task' and a questionnaire on their background and experience. Teachers' responses to four questions which accompanied each anecdotal task were rated according to cognitive process variables associated with problem finding and subsequent problem solving. These included: problem formulation, integrative complexity, quality of point-of-view and developmental teaching strategies. Additional variables of interest to the study included, concern for problem finding and several demographic variables. The results suggested that the variables of problem formulation, integrative complexity and quality of point-of-view as well as the developmental teaching strategies may affect how teachers identify and interpret the student's point-of-view in ill-defined problem situations. Implications for teacher education and studies of teacher thinking were discussed. The need for clinical interviews augmented by classroom observations was emphasized for future studies. Several research questions, related to the cognitive process variables identified in this study to affect the teacher's ability to teach from a developmental perspective, were generated. / Education, Faculty of / Educational and Counselling Psychology, and Special Education (ECPS), Department of / Graduate
456

Use of a developmental theory of parental cognition to construct a model of parental decision-making strategies

Fulmer, Kaye Alison 05 1900 (has links)
In recent years researchers interested in family decision making have argued for the need to apply a conceptual framework to the study of parental decision making about child-rearing issues. This study is an attempt to construct a theory-based model of parental decision-making strategies. Two theoretical approaches were employed; a structural-developmental approach to provide an understanding of parental cognition, and an information processing approach to the study of decision-making strategies. Previous research has demonstrated that pressure of time and task complexity were important in influencing the selection and use of information. These two factors were manipulated by the researcher. A model of parental decision-making strategies was proposed and tested in a pilot study. The decision was made to reduce the number of variables to those which demonstrated the potential to make a significant contribution to an understanding of parental decision making. These variables were tested in the main study. Sixty mothers participated in the study. They represented a wide range of socio-economic and educational backgrounds as well as number of years of parenting experience and age. Participants completed Newberger’s Level of Parental Awareness Interview and four decision tasks about two childrearing issues. The decision tasks were presented on information boards. The model of parental decision-making strategies was tested using multivariate analysis of variance with repeated measures. Significant effects were obtained for level of parental awareness, pressure of time, task complexity and number of years of formal education. The reduced model explained much of the variance in parental decision-making strategies (71%). Specific hypotheses concerning level of parental awareness and information use were supported. The results inform theory and practice. Support was found for the theory-based model and for Liben’s view of a rapprochement between developmental theory and information-processing theory. Parents with more knowledge about parenting used less information and more variability in their decision making. Support was found for Newberger’s measure and construct. Practical implications for parent education were curricula described. / Education, Faculty of / Educational and Counselling Psychology, and Special Education (ECPS), Department of / Graduate
457

Studies in utility theory

Larsson, Stig Owe January 1978 (has links)
Since vonNeumann and Morgenstern made their contributions, the expected utility criterion (EUC) has been the most accepted criterion in decision theory. Following their axiomatic approach justifying EUC, several other studies have been made suggesting the same criterion but under slightly different axiomatic systems. However, critics have found several simple decision problems (called paradoxes) which seem to contradict the conclusions of EUC; that is, the paradoxes contradict one or more of the axioms made to support EUC. The criticisms are based on empirical studies made in regard to the paradoxes. It is not always obvious, however, which axiom(s) is not accepted, since each approach to EUC gives a set of sufficient rather than necessary assumptions for EUC to hold. In Part I of the thesis a set of axioms which are necessary for EUC to hold is specified. Each of these axioms contains a basic assumption of a decision maker's behaviour. Therefore by considering the paradoxes in terms of these axioms, a better understanding is obtained with regard to which properties of EUC seem to be contradicted by the paradoxes. The conclusion of this study shows that most people contradict EUC because it does not differentiate between a "known" risk and an "unknown" risk. In Knight's terminology, there is a distinction between decision making under risk and uncertainty. Most empirical studies show that these differences are of such substantial proportions that there is a questionable justification for using the expected utility criterion for decision making under uncertainty. Although many alternatives to EUC for decision making under uncertainty exist, there are very few criteria for decision problems which fall between risk and uncertainty, that is, partial risk problems. Those existing are of an ad hoc nature. As a normative theory the EUC is far superior to any of these criteria in spite of its lack of distinction between risk and uncertainty. In the second part of the thesis an alternative normative criterion is suggested for decision making under partial risk and uncertainty. As an extension of EUC, this criterion distinguishes between risk and uncertainty. This theory expands on Ellsberg's suggestion that "ambiguity" influences one's preference among a set of alternatives. In this extension a more precise definition of "ambiguity" is needed and one is suggested here as a relation on the inner and outer measure of an event. The extension of EUC is then obtained by considering a more general set function, termed P-measure, which would depend on a set's ambiguity rather than a probability measure on the sets of rewards. It is concluded by an axiomatic development that the P-measure must be a non-negative mono-tonic set function which is not necessarily additive. It is also shown that the standard paradoxes related to paradoxes based on "known" versus "unknown" probabilities may be explained by this method and would therefore suggest an alternative to EUC for decision making under partial risk and uncertainty. / Business, Sauder School of / Unknown
458

Decision analysis applied to ground water exploration

Aginah, Benedict Anekwe January 1979 (has links)
An outline of the essential steps needed in ground water exploration is given. Since drilling for ground water involves a lot of uncertainty, the main concepts of Bayesian decision theory are briefly reviewed. Three models for analyzing ground water decision problems are developed with an emphasis on the well-owner's utility or desirability to actually venture to invest on a water-drilling project. Finally, use of the decision models is Illustrated by applications to a) Ryder Lake District (in British Columbia) - an area where water supply is a problem, with the only source being from underground; and to b) Inches Creek study area where approximately 4500 gallons per minute of ground water is needed for salmon enhancement facilities. / Applied Science, Faculty of / Civil Engineering, Department of / Unknown
459

Groupthink in decision making : testing for its existence, effects and prevention

Kyle, Neil John January 1980 (has links)
Groupthink is a theory concerning decision making developed by Janis (1972) on a case study basis. He uses the theory to explain several international fiascoes such as the Bay of Pigs invasion of Cuba. Highly cohesive, isolated groups operating in stressful circumstances, under highly assertive leaders may support the leader's position in the attempt to maintain group consensus. Experimental research reviewed by the present author is reinterpreted as not supporting the theory. Criticisms concerning the original development of the theory and the possibility of obtaining disconfirming evidence are outlined. The present experiment obtained for subjects 192 staff members from government and corporate organizations. Leadership style, cohesiveness and stress were manipulated to simulate the groupthink conditions. The four-person groups attempted to develop solutions to two current social problems: (1) Canadian immigration, and (2) capital punishment. The sessions were taperecorded and subjects were given post-experimental questionnaires. The questionnaires provided information for manipulation checks and the attempt to observe specific symptoms of groupthink. The audio-tapes were rated by two independent observers for the quality of the decision making discussions. The proposed solutions (in transcript form) were rated for their quality by experts from Immigration and law. Groupthink theory was not supported by the analyses at the various levels. The independent variable manipulations were moderately successful. The results indicated that leadership style played the dominant role in affecting both the group atmosphere and the quality of the decision making. These findings are interpreted as being consistent with earlier research on groupthink theory. It was also found that the time limitations employed in the study influenced the task oriented dimensions of the group processes It was suggested that the role of leadership may be more crucial to group-think theory than is the role of group cohesiveness. However, before reaching a decision on the validity of the groupthink theory based upon the current laboratory research, it is recommended that groupthink be tested in a fashion more appropriate to the level of analysis of the theory. / Arts, Faculty of / Psychology, Department of / Graduate
460

Feminism and collectivity : the integrative function

Light, Linda Louise January 1981 (has links)
Collectivity, (a non-bureaucratic, non-hierarchical participatory-democratic organizational form) has been developed as an alternative to bureaucracy in some Western industrial societies. Such an organizational form, although existing independently of the feminist movement, is one important tool used by that movement to accomplish its goals. Collectivity has a particularly close relationship with what I have called integrative feminism, which focuses on a synthesis of feminine and masculine polarities both in society and within individuals, on a re-definition and sharing of power, and on an emphasis on the feminine sphere in order to redress the present imbalance between the masculine and the feminine in Western society. Collectivity, with its emphasis on democratization and feminization of the work process, shares many of the goals of integrative feminism. The purpose of the thesis, then, is to demonstrate the masculine nature of traditional bureaucracy and the feminine nature of collectivity, and thus the relationship between integrative feminism and collectivity. The point of view taken in this thesis is that the sexual polarization that exists throughout Western industrial society is not a natural outcome of the biological differences between the sexes, but is socially determined and therefore changeable by social means. The thesis argues that this polarization, manifested in one-sided personality development for both sexes and the division of social life into an over-valued masculine (productive) sphere and an under-valued feminine (maintenance) sphere, which emphasize different functions, characteristics and values, is destructive to human and social growth. It also argues that sexual polarization is a significant factor in the crisis the world is now facing, which involves the domination of the powerless by the powerful, domestic and international conflict, and, in the West, too-rapid growth and over-consumption. While certain limitations restrict the general application of collectivity as a universal organizational form (for example, social demands for productivity and disparity between the ideology of collectivity and the dominant ideology), it may be that elements of collectivity can be effectively combined with elements of bureaucracy in a variety of contexts. The data on which the argument is based includes the literature of feminism, organizations, and social movements; previous research done on the Vancouver Women's Health Collective; and personal experience in social movement activity. / Arts, Faculty of / Sociology, Department of / Graduate

Page generated in 0.0773 seconds