Thesis (Ph. D.)--California Institute of Technology, 1954. / Advisor names found in the Acknowledgments pages of the thesis. Title from home page. Viewed 02/18/2010. Includes bibliographical references.

New Product Development is vital to the performance of high-tech firms given the rapid change in technology and markets that they face. Drawing on the ambidexterity literature this study focuses on how firms can employ Ambidextrous Market Learning (AML), that is, the use of exploratory and exploitative market learning strategies simultaneously, to develop successful innovative products. Despite the exponential growth of studies focusing on ambidexterity, the literature portrays the ambidexterity concept as a present or absent like phenomena. However, in the current study, AML is conceptualised as a continuum of market knowledge that acts as a key source essential in creating customer value in the form of new products. Whilst research into ambidexterity contains abundant evidence of the positive effects of ambidexterity on firm performance, yet there is little discussion in the literature on the effects of AML on product advantage and the role of product innovativeness. A conceptual model comprising the relationship between AML, product advantage and product innovativeness is developed and empirically tested using 178 UK-based high-tech firms. The findings indicate that AML firms tend to develop products that have high product advantage. The study further focuses on how product innovativeness and product advantage constructs interact to create new product financial performance. Findings also suggest that marketing and technological discontinuity (product innovativeness from the firm s perspective) respectively has a negative and a positive moderating impact on product advantage. In addition, modelling product innovativeness from the customers perspective (customer discontinuity) in the same model sheds new light on the relationship between product advantage, product innovativeness and product performance. By further examining the moderating effects of marketing and technological discontinuity on the link between AML and product advantage, the analyses reveals the different scenarios in which the benefits of AML firms may outweigh its implementation cost.

This thesis includes three substantive empirical studies (in Chapters 3, 4 and 5), where each study uses the same econometric methodology, named Regression Discontinuity design, which has an attractive feature - local randomisation. This feature has given the superiority of the method over the other evaluation methods in estimating unbiased treatment effects. Besides, the fuzzy Regression Discontinuity design can control for the endogeneity of the treatment variable, which is another advantage of the method. In each of the studies considered, the endogeneity problem exists. The application of the fuzzy Regression Discontinuity design is itself a contribution in each of the studies. Moreover, each study contributes in its own field. In Chapter 3, we investigate how much the Social Safety Net programs, that provide free food, or cash, or both to the food insecure households in Bangladesh, improve calorie consumption of the beneficiary households. Using Household Income and Expenditure Survey 2005, we find that the effect of the programs is around 843 kilo calorie, which is substantial compared to the previous studies. In Chapter 4, we examine how much was the impact of Education Maintenance Allowance, a program that provided weekly allowance to the young people in Years 12 and 13 in England, on the staying rate in the post compulsory full-time education. The program was abolished in 2010. Using the Longitudinal Survey of Young People in England, we find that the effect of the program was substantial - around 15 percent. The effect of a £1 increase in weekly allowance was around 1 percent. These effects were mainly on the white young people. Using the household survey data - Family Expenditure Survey (1968-2009) - in UK, Chapter 5 establishes that before 1981 consumption substantially fell at the retirement age. This fall is less severe after 1980. However, throughout the data period, consumption fall at the retirement age is fully explained by the expected fall in income, which contradicts the life cycle model, where a consumption growth is independent of an income growth.

The following document presents my dissertation composition. The work is written for eight performers, including flute, clarinet, saxophone, French horn, percussion, violin, viola, and Double Bass. The duration of the piece is approximately sixteen minutes, in a single movement. This composition explores forms of discontinuity within continuous textures, and includes particular theatrical and staging elements.

This dissertation studies household income and consumption. In the first chapter, I identify the causal effect of retirement on health service utilization in China. In the second chapter, I investigates the impact that retirement has on the family support network of “sandwich” generations in China. In the third chapter, I propose a new estimator for linear quantile regression models with generated regressors, and apply it to study Engel curves for various commodity consumption for families in the UK. In the first chapter, I apply a regression discontinuity design by exploiting the exogenous mandatory retirement age rules in China in order to identify the causal effect of retirement on health service utilization. In China, the social insurance Urban Employee Basic Medical Insurance (UEBMI) provision continues after individuals retire. Employees, however, stop paying the premium and enjoy reduced cost sharing after they retire. Individual medical expenses, insurance costs, and benefits are recorded in the China Household Finance Survey 2013 (CHFS). Significantly, males and females respond differently to this decrease in the relative price of health insurance at the time of retirement. Females are generally more willing to increase their out-of-pocket expenditures in order to take advantage of better health insurance benefits and utilize more medical care. Males, by contrast, do not respond to this change in relative price in the same manner. In the second chapter, I investigates the impact that retirement has on the family support networks of “sandwich” generations in China. These middle-aged households have an inter-generational support network that includes both upward transfers (their parents or parents-in-law), as well as downward transfers (their children). I use micro data from CHARLS (China Health and Retirement Longitudinal Study) concerning middle-aged and elderly households in order to evaluate the changes that retirement can have on this family support network, primarily by exploiting the exogenous mandatory retirement age rules in China. I make the identifying assumption that inter-generational transfers would evolve more smoothly if households would not retire and apply a regression discontinuity approach. I find that retirement induces “sandwich” generations to switch roles in the private network as well as in the public transfer channel; indeed, is 55 percentage point more likely that households will switch from resource providers to resource recipients in the channel of private transfers. In addition, these “sandwich” generations are about 47 percentage point more likely to receive money from their non-coresident children when they retire. In the third chapter, we studies estimation and inference for linear quantile regression models with generated regressors. We suggest a practical two-step estimation procedure, where the generated regressors are computed in the first step. The asymptotic properties of the two-step estimator, namely, consistency and asymptotic normality are established. We show that the asymptotic variance-covariance matrix needs to be adjusted to account for the first-step estimation error. We propose a general estimator for the asymptotic variance-covariance, establish its consistency, and develop testing procedures for linear hypotheses in these models. Monte Carlo simulations to evaluate the finite-sample performance of the estimation and inference procedures are provided. Finally, we apply the proposed methods to study Engel curves for various commodities using data from the UK Family Expenditure Survey. We document strong heterogeneity in the estimated Engel curves along the conditional distribution of the budget share of each commodity. The empirical application also emphasizes that correctly estimating confidence intervals for the estimated Engel curves by the proposed estimator is of importance for inference.

In a fast-paced office setting, information workers inevitably experience expected and unexpected interruptions daily. As the volume and the diversity of information and application types grow, the impact of frequent interruptions on their task performance gets more severe. To manage the negative effects of interruptions on work performance, workers often engage in task management activities to ensure they are better prepared to resume suspended task less stressfully. However, managing tasks causes additional cognitive burden and a time cost to users who already are experiencing the tight attention and time economies. This dissertation presents an approach to augmenting users' task performance by allowing them to manage and retrieve desired work contexts with ease. The Context Browser, the implementation of the proposed approach, is designed to help the users to explore narratives of their workspace manner and restore their previous work contexts. The goals of implementing the Context Browser are to 1) unload the users? burden of taking care of their task-related or task status information promptly and thus help them focus solely on executing a given task, 2) allow them to browse their previous workspace intuitively, and 3) enhance continuity of their tasks by supporting them to retrieve desired work context more quickly and easily. In order to validate the proposed approach, a user study comparing task performances of the group with the Context Browser to the one without the Context Browser was conducted. The study produced both quantitative and qualitative results. The study confirmed that with the Context Browser subjects expressed better quantitative numbers than the ones without. Subjects using the Context Browser were able to restore and retrieve their desired work setting and task-related information more quickly and correctly. Qualitative results showed that the subjects using the Context Browser found that various contextual cues and the interfaces responsible for providing the cues offered effective artifacts to help them recover both cognitive and work contexts, while the other subjects experienced a difficult time in restoring the desired contexts that were necessary to perform their assigned tasks. In addition, we re-invited 6 subjects from the group without the Context Browser 6 weeks after the study. We asked them to perform the same tasks as the ones they did 6 weeks before with the Context Browser. It showed that with the Context Browser they outperformed their previous performance even after a lengthy period.

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Os trabalhos artísticos e exposições empreendidos durante a pesquisa de Mestrado - 2014 a 2016 - foram motivados por investigações e vivências na cidade de São Paulo. Configurados a partir de reflexões sobre a paisagem urbana e sobre aspectos históricos e contemporâneos peculiares a essa cidade, à sua arquitetura, ao seu urbanismo e às suas narrativas. No entanto, algumas obras excedem o âmbito desta cidade. Pretende-se que seja comum a todas elas uma experiência poética centrada na produção de descontinuidades espaciais e temporais. O \"tempo\" - a duração temporal de uma experiência, a manipulação de sua intensidade, de sua continuidade ou de sua paralização - foi elemento estudado em todos os casos. / The artworks and exhibitions undertaken during Master research - 2014 to 2016 - were motivated by investigation and experiences in the city of São Paulo. They took shape from reflections upon the urban landscape and on historical and contemporary aspects peculiar to this city, its architecture, its urbanism and its narratives. However, some works are beyond the scope of this city. It is intended to be common to all propositions a poetic experience centered on the production of spatial and temporal discontinuities. The \"time\" - the temporal duration of an experience, the elaboration of its intensity, its continuity or its paralysis - was studied in every case.

Os trabalhos artísticos e exposições empreendidos durante a pesquisa de Mestrado - 2014 a 2016 - foram motivados por investigações e vivências na cidade de São Paulo. Configurados a partir de reflexões sobre a paisagem urbana e sobre aspectos históricos e contemporâneos peculiares a essa cidade, à sua arquitetura, ao seu urbanismo e às suas narrativas. No entanto, algumas obras excedem o âmbito desta cidade. Pretende-se que seja comum a todas elas uma experiência poética centrada na produção de descontinuidades espaciais e temporais. O \"tempo\" - a duração temporal de uma experiência, a manipulação de sua intensidade, de sua continuidade ou de sua paralização - foi elemento estudado em todos os casos. / The artworks and exhibitions undertaken during Master research - 2014 to 2016 - were motivated by investigation and experiences in the city of São Paulo. They took shape from reflections upon the urban landscape and on historical and contemporary aspects peculiar to this city, its architecture, its urbanism and its narratives. However, some works are beyond the scope of this city. It is intended to be common to all propositions a poetic experience centered on the production of spatial and temporal discontinuities. The \"time\" - the temporal duration of an experience, the elaboration of its intensity, its continuity or its paralysis - was studied in every case.

The surface roughness of unfilled rock discontinuities has a major influence on the hydro-mechanical behaviour of discontinuous rock masses. Although it is widely recognized that surface roughness is comprised of large-scale (waviness) and small-scale (unevenness) components, most investigations of surface roughness have been restricted to small fracture surfaces (<1m2). Hence, the large-scale components of roughness are often neglected. Furthermore, these investigations typically define roughness using two-dimensional profiles rather than three-dimensional surfaces, which can lead to biased estimates of roughness. These limitations have led to some contradictory findings regarding roughness scale effects. This thesis aims to resolve some of these issues. The main findings indicate that discontinuity roughness increases as a function of the sampling window size contrary to what is commonly assumed. More importantly, it is shown that the estimated roughness significantly decreases as the resolution of surface measurements decrease, which could lead to the under estimations of roughness and, consequently, discontinuity shear strength.