We show that, for a utility function U: R to R having reasonable asymptotic elasticity, the optimal investment process H. S is a super-martingale under each equivalent martingale measure Q, such that E[V(dQ/dP)] < "unendlich", where V is conjugate to U. Similar results for the special case of the exponential utility were recently obtained by Delbaen, Grandits, Rheinländer, Samperi, Schweizer, Stricker as well as Kabanov, Stricker. This result gives rise to a rather delicate analysis of the "good definition" of "allowed" trading strategies H for the financial market S. One offspring of these considerations leads to the subsequent - at first glance paradoxical - example. There is a financial market consisting of a deterministic bond and two risky financial assets (S_t^1, S_t^2)_0<=t<=T such that, for an agent whose preferences are modeled by expected exponential utility at time T, it is optimal to constantly hold one unit of asset S^1. However, if we pass to the market consisting only of the bond and the first risky asset S^1, and leaving the information structure unchanged, this trading strategy is not optimal any more: in this smaller market it is optimal to invest the initial endowment into the bond. (author's abstract) / Series: Working Papers SFB "Adaptive Information Systems and Modelling in Economics and Management Science"

This study examines knowledge of grammar by receptive bilinguals (RBs) - heritage speakers who describe themselves as capable of fluent comprehension in Labrador Inuttitut (an endangered dialect of Inuktitut), but of little or no speech production in it. Despite the growing research on incomplete acquisition, RBs have yet to be studied as a specific population. Participants (8 fluent bilinguals, 17 RBs, 3 low-proficiency RBs) performed a morpheme comprehension task and a grammaticality judgment task. General measures of their comprehension and production abilities included a story retelling task as an overall assessment of comprehension, a vocabulary test, an elicited imitation task, and a production task. This data was complemented by language behaviour interviews. The results showed that RBs have good, though not perfect, comprehension and basic vocabulary, but speech production is very difficult for them. They have grammatical knowledge, but it is incomplete: Knowledge of some structures is robust, and their comprehension is fluent (past vs. future contrast, aspectual morphemes); others are missing (temporal remoteness degrees); and yet for others (case and agreement), RBs have the category and know its position in the word structure, but have difficulty connecting the features with the morphemes expressing them. These findings explain the significant asymmetry between comprehension and production in RBs: In comprehension, incomplete knowledge may result in loss of some aspects of meaning, but in many cases it can be compensated for by pragmatic knowledge and extralinguistic context, while in production, it can result in the selection of an incorrect morpheme or inability to select a morpheme. Low-proficiency RBs have partial comprehension, small vocabulary, and almost no production. They do not understand most functional morphemes; however, they show knowledge of the basic properties such as the position of the obligatory agreement marker on the verb. This study provides data on an understudied language and an understudied population at the extreme end of unbalanced bilingualism. The findings have implications both for the psycholinguistics of bilingualism and for language revitalization, especially in the context of a language shift in indigenous language communities, where RBs are often the last generation to have competence in the indigenous language.

This study examines knowledge of grammar by receptive bilinguals (RBs) - heritage speakers who describe themselves as capable of fluent comprehension in Labrador Inuttitut (an endangered dialect of Inuktitut), but of little or no speech production in it. Despite the growing research on incomplete acquisition, RBs have yet to be studied as a specific population. Participants (8 fluent bilinguals, 17 RBs, 3 low-proficiency RBs) performed a morpheme comprehension task and a grammaticality judgment task. General measures of their comprehension and production abilities included a story retelling task as an overall assessment of comprehension, a vocabulary test, an elicited imitation task, and a production task. This data was complemented by language behaviour interviews. The results showed that RBs have good, though not perfect, comprehension and basic vocabulary, but speech production is very difficult for them. They have grammatical knowledge, but it is incomplete: Knowledge of some structures is robust, and their comprehension is fluent (past vs. future contrast, aspectual morphemes); others are missing (temporal remoteness degrees); and yet for others (case and agreement), RBs have the category and know its position in the word structure, but have difficulty connecting the features with the morphemes expressing them. These findings explain the significant asymmetry between comprehension and production in RBs: In comprehension, incomplete knowledge may result in loss of some aspects of meaning, but in many cases it can be compensated for by pragmatic knowledge and extralinguistic context, while in production, it can result in the selection of an incorrect morpheme or inability to select a morpheme. Low-proficiency RBs have partial comprehension, small vocabulary, and almost no production. They do not understand most functional morphemes; however, they show knowledge of the basic properties such as the position of the obligatory agreement marker on the verb. This study provides data on an understudied language and an understudied population at the extreme end of unbalanced bilingualism. The findings have implications both for the psycholinguistics of bilingualism and for language revitalization, especially in the context of a language shift in indigenous language communities, where RBs are often the last generation to have competence in the indigenous language.

Thesis (Ph.D.) - University of St Andrews, May 2007.

abstract: This work is driven by two facts. First, the majority of households in the U.S. obtain health insurance through their employer. Second, around 20% of working age households choose not to purchase health insurance. The link between employment and health insurance has potentially large implications for household selection into employment and participation in public health insurance programs. In these two essays, I address the role of public and private provisions of health insurance on household employment and insurance decisions, the distribution of welfare, and the aggregate economy. In the first essay, I quantify the effects of key parts of the 2010 health care reform legislation. I construct a lifecycle incomplete markets model with an endogenous choice of health insurance coverage and calibrate it to U.S. data. I find that the reform decreases the fraction of uninsured households by 94% and increases ex-ante household welfare by 2.3% in consumption equivalence. The main driving force behind the reduction in the uninsured population is the health insurance mandate, although I find no significant welfare loss associated with the elimination of the mandatory health insurance provision. In the second essay, I provide a quantitative analysis of the role of medical expenditure risk in the employment and insurance decisions of households approaching retirement. I construct a dynamic general equilibrium model of the household that allows for self-selection into employment and health insurance coverage. I find that the welfare cost of medical expenditure risk is large at 5% of lifetime consumption equivalence for the non-institutionalized population. In addition, the provision of health insurance through the employer accounts for 20% of hours worked for households ages 60-64. Finally, I provide an quantitative analysis of changes in Medicare minimum eligibility age in a series of policy experiments. / Dissertation/Thesis / Ph.D. Economics 2011

We study a family of random walks defined on certain Euclidean lattices that are related to incidence matrices of balanced incomplete block designs. We estimate the return probability of these random walks and use it to determine the asymptotics of the number of balanced incomplete block design matrices. We also consider the problem of collisions of independent simple random walks on graphs. We prove some new results in the collision problem, improve some existing ones, and provide counterexamples to illustrate the complexity of the problem.

abstract: Bayesian networks are powerful tools in system reliability assessment due to their flexibility in modeling the reliability structure of complex systems. This dissertation develops Bayesian network models for system reliability analysis through the use of Bayesian inference techniques. Bayesian networks generalize fault trees by allowing components and subsystems to be related by conditional probabilities instead of deterministic relationships; thus, they provide analytical advantages to the situation when the failure structure is not well understood, especially during the product design stage. In order to tackle this problem, one needs to utilize auxiliary information such as the reliability information from similar products and domain expertise. For this purpose, a Bayesian network approach is proposed to incorporate data from functional analysis and parent products. The functions with low reliability and their impact on other functions in the network are identified, so that design changes can be suggested for system reliability improvement. A complex system does not necessarily have all components being monitored at the same time, causing another challenge in the reliability assessment problem. Sometimes there are a limited number of sensors deployed in the system to monitor the states of some components or subsystems, but not all of them. Data simultaneously collected from multiple sensors on the same system are analyzed using a Bayesian network approach, and the conditional probabilities of the network are estimated by combining failure information and expert opinions at both system and component levels. Several data scenarios with discrete, continuous and hybrid data (both discrete and continuous data) are analyzed. Posterior distributions of the reliability parameters of the system and components are assessed using simultaneous data. Finally, a Bayesian framework is proposed to incorporate different sources of prior information and reconcile these different sources, including expert opinions and component information, in order to form a prior distribution for the system. Incorporating expert opinion in the form of pseudo-observations substantially simplifies statistical modeling, as opposed to the pooling techniques and supra Bayesian methods used for combining prior distributions in the literature. The methods proposed are demonstrated with several case studies. / Dissertation/Thesis / Doctoral Dissertation Industrial Engineering 2016

Magister Public Health - MPH / Ethiopia has achieved its target for Millennium Development Goal 4 by recording 69 %reduction in its under-five mortality. The proportion of fully immunized children in Ethiopia has increased from 14 % in 2000 to 24 % in 2011. Though progress has been made, about 3 out of 4 children still remain incompletely immunized. The purpose of this study is to determine the socio-demographic and socioeconomic factors associated with incomplete immunization among children aged 12-23 months in Ethiopia. This study is based on secondary analysis of the 2011 Ethiopia Demographic and Health Survey. Information on 1,889 mothers of children aged 12–23 months were extracted from the children dataset. Records from vaccination cards and mothers’ self-reported data were used to determine vaccine coverage. The association between child immunization status and determinants of non-utilization of immunization services was assessed using bivariate and multivariate analyses. The findings of this study showed that the prevalence of incompletely immunized children is 70.9%. Children of mothers from the poor (AOR = 2.27; 95 % CI: 1.34 – 3.82) wealth quintile were more likely to be incompletely immunized. Children of mothers from Affar (AOR = 15.80; 95 % CI: 7.12 – 35.03), Amhara (AOR = 4.27; 95 %CI: 2.31 – 7.88), Oromiya (AOR = 8.10; 95 % CI: 4.60 – 14.25), Somali (AOR = 4.91;95 % CI: 2.65 – 9.10), Benishangul-Gumuz (AOR = 4.20; 95% CI: 2.34 – 7.57),Southern Nations Nationalities and Peoples’ (AOR = 4.76; 95 % CI: 2.53 – 8.94), Gambela (AOR = 7.75; 95 % CI: 3.68 – 16.30) and Harari (AOR = 3.22; 95 % CI: 1.77 –5.89) regions were more likely to be incompletely immunized. Mothers with inadequate exposure to media (AOR = 1.60; 95% CI: 1.21 – 2.14), who are not aware of community conversation programme (AOR = 1.80; 95% CI: 1.40 – 2.32) and who attended no antenatal care (AOR = 2.21; 95% CI: 1.72 – 2.83) were more likely to have incompletely immunized children. Despite efforts to increase rates of childhood immunization, the proportion of children with incomplete immunization in Ethiopia is considerably high. Therefore, targeted interventions at the identified socio-demographic factors are needed to increase immunization rates.

No description available.

In this thesis two dierent problems regarding real options are studied. The rst paper discusses the valuation of a timing option in an irreversible investment when the underlying model is incomplete. It is well known that in a complete model there is no nite optimal time at which to invest if the underlying asset, in our case the value of the developed project, does not pay out any strictly positive cash ows. In an incomplete model, the situation is dierent. Depending on the market price of risk in the model, there could be an optimal nite investment time even though the underlying asset does not pay out any strictly positive cash ows. Several examples of incomplete models are analyzed, and the value of the investment opportunity is calculated in each of them. The second paper concerns the valuation of random start American perpetual options. This type of perpetuate American option has the feature that it can not be exercised until a random time has occured. The reason for studying this type of option is that it provides a way of modelling the initiating of a project, e.g. the optimal time to build on a piece of land, which can not occur until a permit, or some other form of clearance, is given. The random time in the project application represents the time at which the permit is given. Two concrete examples of how to calculate the value of random start options is given. / <p>QC 20160607</p>