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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.
61

Executive compensation and matching in the CEO labor market

Nickerson, Jordan Lee 09 July 2014 (has links)
This study examines the matching of CEOs to firms and the compensation earned by such managers in a competitive labor market. I first develop a simple competitive equilibrium model and derive predictions regarding the change in wages when an inelastic supply of CEO labor cannot match an increase in demand. The model predicts that the CEO pay-size elasticity increases when more firms compete for a fixed supply of managers. I then empirically test this prediction using industry-level IPO waves as a proxy for increased competition among firms for CEOs. Consistent with the model, I find that pay-size elasticity increases with an increase in an industry's IPO activity. I also find that increased IPO activity leads to a greater likelihood of executive transitions between firms. Overall, the findings point to the substantial role market forces play in the determination of pay in the CEO labor market. I then use a structural model to examine the distortionary effects of frictions in the CEO labor market. I estimate the switching cost to be 20% of the median firm's annual earnings. While reduced-form estimates of the switching cost serve as a lower bound on the reduction in firm value, they underestimate the overall effect which also includes the resulting inefficient firm-CEO matches. Using counterfactual analysis, the switching cost is estimated to decrease the median firm's value by 4.8%, four times larger than the reduced-form estimate. / text
62

Effects of Pay Variability and Mutual Monitoring on Employee Effort and Contract Choice

Mortenson, Kristian G January 2008 (has links)
A primary cause of income volatility for employees is job loss due to firm downsizing. Economists have suggested that firms use share contracts rather than wage contracts as one possible solution to downsizing. In my experimental setting employment contracting involves an employer who hires two employees to produce output. In each of 31 rounds, employees choose between a wage contract (status quo) and a share contract with an employer-set sharing rule. I manipulate whether the share contract incorporates a form of mutual monitoring and examine the effects on employee effort, contract preference, and welfare. The results show that, compared to wage contracts, subjects exert more effort and have higher welfare when they choose share contracts. Incorporating mutual monitoring into the share contract also increases total effort and subject welfare but does not lead to an increase in the use of share contracts.
63

System Identification and Adaptive Compensation of Friction in Manufacturing Automation Systems

Turhan, Mustafa Hakan 13 September 2013 (has links)
Industrial demands for more efficient machine tool systems have been significantly increased. In order to obtain high performance machine tool systems, researchers are focused on enhancing functioning of various components of machine tool systems. Feed drives are important component of the most of machine tool systems such as computer numerical control (CNC) machines for achieving desirable performance. An essential research stream of current interest aiming enhancement of feed drive performance is construction of control methods that help to decrease tool positioning errors in the system. An effective approach for mitigation or reduction of positioning errors is modeling, identifying, and compensating friction in appropriate manner. In addition, accurate modeling of feed drive systems is essential in elimination of these positioning errors. In this thesis, the precision control of feed drives is studied using several different control methods. Firstly, the feed drive type that has common use in machine tools is chosen to be main focus for this research, namely ball screw drive. Different dynamic models of ball screw drive are shown in detail. In addition, some of the nonlinearities that affect ball screw dynamics such as friction affects are discussed. Friction modeling needs to be performed realistically and accurately in order to design an effective compensator to cancel friction effects. In general, the friction models are divided into two categories; classic (static) and dynamic friction models. In this thesis, we present details of these models and derive linear parametrization of the key ones. Based on the derived linear parametric models, we design a least-squares on-line friction estimator and adaptive friction compensation scheme. The performance of these designs are verified via simulation and real-time experimental tests. Noting that the parameters of the base rigid body model, i.e., inertia and viscosity constants, need to be known precisely for effective high precision control tasks, including the aforementioned adaptive schemes. The second part of the thesis focuses on off-line identification of these key base model parameters. In this part, we present a real-life case study on identification of plant and built-in controller parameters and a simulator design based on this identification for a grinding CNC machine used in a gear manufacturing company.
64

Land Rights and Expropriation in Ethiopia

Ambaye, Daniel Weldegebriel January 2013 (has links)
This study examines and analyses the expropriation laws and practices in Ethiopia. The objective of the thesis is to analyze and describe the land rights and expropriation laws in Ethiopia and to compare them with the practice in order to determine the fairness of compensation. The study is made against the Ethiopian Constitution and other subsidiary legislations which provide the basic land rights and the nature and details of expropriation. The basic argument made in this thesis is that even if the Ethiopian Constitution provides and guarantees common ownership of land (together with the state) to the people, this right has not been fully realized whether in terms of land accessibility, enjoyablity, and payment of fair compensation in the event of expropriation. The reasons have to do either with the faulty nature of the laws or with their implementation by public authorities. From the outset, the constitution excludes land as a subject of compensation. For this reason, land is being excluded from the compensation package and hence it has no value for the holder. Urban land holders are denied location value of their property, which they can collect it otherwise during sale, and hence the compensation becomes unfair. Similarly, rural farmers are denied compensation for the complete loss of their farm land. The denial of compensation for the value of the land is categorically in contradiction with the very principle of joint ownership of land by the people and the state. There are also other reasons which are related to the law or its practical applicability, such as valuation process which reduces the amount of compensation. There are also property interests which are not included as compensable interests. Payment of compensation is one factor for secure property right and hence sustainable development. To ensure fair compensation in the event of compensation, a legal and policy level reform is necessary to address and amend the existing problems. Further, to harmonize the laws and practices is imperative to reduce the amount of injustice existed in today’s expropriation procedure in Ethiopia. / <p>QC 20131122</p>
65

Investigation of Reactive Power Control and Compensation for HVDC systems

Zhang, Yi 07 October 2011 (has links)
This thesis attempts to investigate the performance of various reactive power compensation devices, examine the mechanism of reactive power compensation for HVDC systems, and develop guidelines for the design of reactive power compensation schemes for HVDC systems. The capabilities of various reactive power compensators to enhance power system stability are compared in both steady and transient states. An understanding of the capabilities of these compensators provides a basis for further investigation of their performance in HVDC systems. The reactive power requirements of HVDC converters are studied. The voltage dependencies of the HVDC converters at different control modes are derived, which allow for predictions of how HVDC converters impact AC system voltage stability. The transient performance of reactive power compensation options for HVDC Systems is studied by comparing their behavior during DC fault recovery, Temporary Overvoltage (TOV), and commutation failure. How to quantify the system strength when reactive compensators are connected to the converter bus is investigated. A new series of indices are developed based on the Apparent Short Circuit Ratio Increase (ASCRI). The inertia of a synchronous condenser and its impact on the frequency stability of an AC/DC system are discussed. By modelling the inverter side AC system in greater detail, the frequency stability and rotor angle stability following fault transients is examined based on time domain simulation. Finally, a guideline for designing dynamic reactive power compensation for HVDC systems is proposed.
66

Investigation of Reactive Power Control and Compensation for HVDC systems

Zhang, Yi 07 October 2011 (has links)
This thesis attempts to investigate the performance of various reactive power compensation devices, examine the mechanism of reactive power compensation for HVDC systems, and develop guidelines for the design of reactive power compensation schemes for HVDC systems. The capabilities of various reactive power compensators to enhance power system stability are compared in both steady and transient states. An understanding of the capabilities of these compensators provides a basis for further investigation of their performance in HVDC systems. The reactive power requirements of HVDC converters are studied. The voltage dependencies of the HVDC converters at different control modes are derived, which allow for predictions of how HVDC converters impact AC system voltage stability. The transient performance of reactive power compensation options for HVDC Systems is studied by comparing their behavior during DC fault recovery, Temporary Overvoltage (TOV), and commutation failure. How to quantify the system strength when reactive compensators are connected to the converter bus is investigated. A new series of indices are developed based on the Apparent Short Circuit Ratio Increase (ASCRI). The inertia of a synchronous condenser and its impact on the frequency stability of an AC/DC system are discussed. By modelling the inverter side AC system in greater detail, the frequency stability and rotor angle stability following fault transients is examined based on time domain simulation. Finally, a guideline for designing dynamic reactive power compensation for HVDC systems is proposed.
67

Three Essays on Total Returns to the Employment Relationship

Lee, Byron Y. S. 31 August 2011 (has links)
This dissertation examines the total returns to the employment relationship from a variety of perspectives. In the first chapter, I examine different forms of training and study its influence on individual turnover. My second chapter examines the impact of mandatory volunteer/work experience in high school on the employment and wage decisions of youths. In my final chapter, I examine flexible work hours as a moderator in the relationship between workplace strategy and organizational performance. The first chapter highlights the importance of the type of training provided to the employee in order to avoid voluntary turnover. I compare the impact of institutional training compared to course training on voluntary turnover. Estimates indicate that employees who receive course training are more likely to leave the firm for another job, while employees who receive institutional training are more likely to stay with the firm. The results indicate that different types of training have differential impacts on the employee’s turnover decision. The second chapter utilizes a provincial policy reform that requires either working at a paid job or volunteering as a mandatory high school graduation requirement and examines its impact on employment outcomes. I propose that this reform causes a change in the perceptions of work by individuals which may lead them to sacrifice income for an altruistic purpose. In addition, the low quality of jobs found working or volunteering in high school may result in a distaste for work and hence provide motivation for enrolling in post-secondary education. The empirical results support this argument as the reform resulted in an increased likelihood of high school graduates to pursue post-secondary education, while those who entered the labour force had a lower probability of employment and lower wages. The final chapter examines the generalizeable conditions under which flexible work schedules are beneficial to firm performance. I find that flextime is not a best practice that is applicable across all firm environments. Instead, flextime only increases profitability when implemented within a workforce strategy focused on employees. Conversely, flextime when implemented with a cost-reduction strategy has detrimental effects on firm profits.
68

Three Essays on Total Returns to the Employment Relationship

Lee, Byron Y. S. 31 August 2011 (has links)
This dissertation examines the total returns to the employment relationship from a variety of perspectives. In the first chapter, I examine different forms of training and study its influence on individual turnover. My second chapter examines the impact of mandatory volunteer/work experience in high school on the employment and wage decisions of youths. In my final chapter, I examine flexible work hours as a moderator in the relationship between workplace strategy and organizational performance. The first chapter highlights the importance of the type of training provided to the employee in order to avoid voluntary turnover. I compare the impact of institutional training compared to course training on voluntary turnover. Estimates indicate that employees who receive course training are more likely to leave the firm for another job, while employees who receive institutional training are more likely to stay with the firm. The results indicate that different types of training have differential impacts on the employee’s turnover decision. The second chapter utilizes a provincial policy reform that requires either working at a paid job or volunteering as a mandatory high school graduation requirement and examines its impact on employment outcomes. I propose that this reform causes a change in the perceptions of work by individuals which may lead them to sacrifice income for an altruistic purpose. In addition, the low quality of jobs found working or volunteering in high school may result in a distaste for work and hence provide motivation for enrolling in post-secondary education. The empirical results support this argument as the reform resulted in an increased likelihood of high school graduates to pursue post-secondary education, while those who entered the labour force had a lower probability of employment and lower wages. The final chapter examines the generalizeable conditions under which flexible work schedules are beneficial to firm performance. I find that flextime is not a best practice that is applicable across all firm environments. Instead, flextime only increases profitability when implemented within a workforce strategy focused on employees. Conversely, flextime when implemented with a cost-reduction strategy has detrimental effects on firm profits.
69

Do Older and Younger Adults Use and Benefit from Memory Aids?

Schryer, Emily 20 June 2012 (has links)
This research examines age differences in the use and value of memory compensation strategies for everyday memory tasks. Chapter 1 reviews the literature on memory compensation and aging. According to Selective Optimization with Compensation (SOC) model, older adults may be more likely than younger adults to take advantage of memory compensation strategies when they are available. Chapter 2 describes a diary study in which older and younger participants rated the extent to which they use compensation strategies in everyday life and reported everyday memory errors over the course of a week. Older adults reported fewer memory errors than younger adults and more use of memory aids. However, use of memory aids was unrelated to frequency of memory errors in either age group. Chapter 3 reports a laboratory experiment on the use of memory aids for recalling phone messages. Participants listened to phone messages while simultaneously completing a seating chart, and were asked to report the content of the messages to the experimenter. Participants were either allowed to use a memory aid for the phone message task, or not. Older participants reported using compensation strategies more frequently in everyday life, but they were no more likely than younger participants to search for or employ an aid in the phone message task. Using a memory aid was differentially beneficial, improving performance more for older than younger participants. In Chapter 4, participants completed two phone message recall and two seating plan tasks. Participants were encouraged to use whatever in the room that they might find helpful. On one round of tasks a pen was tied to a clipboard and participants could use it to write down the phone messages. On the other round no pen was available. The order of the trials was counterbalanced across participants. This design examined the calibration between participants’ use of memory aids and their performance on the recall task – whether participants’ performance on the first trial predicted their subsequent use of memory aids, and whether participants who chose to use a memory aid when it was available on the first trial performed particularly poorly on the second trial when no aid was present. As in Study 1, older adults reported using memory aids more frequently in everyday life but age was unassociated with whether or not participants used the pen when one was available. There was little evidence of calibration. Participants’ memory performance on an initial trial had little impact on their use of a memory aid on a subsequent trial. Participants who used a memory aid on the first trial actually recalled more phone message details on the second trial (without the aid) than those who did not. This was true for both age groups. Chapter 5 reflects on older and younger adults self-reported and observed uses of memory compensation strategies. Across all 3 studies older adults reported using external memory aids more frequently in everyday life. However, contrary to the SOC model, in Studies 2 and 3 there were no age differences in older and younger adults’ use of a pen to write down phone messages on the lab task. Nor was participants’ choice to use the memory aid associated with their unaided performance on the task. These results do not support the prediction derived from SOC that older adults use compensation strategies more frequently or more sensitively than younger adults. However, using the memory did improve performance on the task more for older than for younger adults. These results support the hypothesis that external memory aids are a particularly valuable strategy for older adults and suggest the need to better understand why some individuals engage in compensation use and others do not.
70

The association between compensation and outcome after injury

Harris, Ian A January 2006 (has links)
Doctor of Philosophy / Work-related injuries and road traffic injuries are common causes of morbidity and are major contributors to the burden of disease worldwide. In developed countries, these injuries are often covered under compensation schemes, and the costs of administering these schemes is high. The compensation systems have been put in place to improve the health outcomes, both physical and mental, of those injured under such systems; yet there is a widespread belief, and some evidence, that patients treated under these schemes may have worse outcomes than if they were treated outside the compensation system. Chapter One of this thesis explores the literature pertaining to any effect that compensation may have on patient outcomes. It is noted that the concept of “compensation neurosis” dates from the nineteenth century, with such injuries as “railway spine”, in which passengers involved in even minor train accidents at the time, would often have chronic and widespread symptoms, usually with little physical pathology. Other illnesses have been similarly labelled over time, and similarities are also seen in currently diagnosed conditions such as repetition strain injury, back pain and whiplash. There are also similarities in a condition that has been labelled “shell shock”, “battle fatigue”, and “post-traumatic stress disorder”; the latter diagnosis originating in veterans of the Vietnam War. While there is evidence of compensation status contributing to the diagnosis of some of these conditions, and to poor outcomes in patients diagnosed with these conditions, there is little understanding of the mechanism of this association. In contrast to popular stereotypes, the literature review shows that malingering does not contribute significantly to the effect of compensation on health outcomes. Secondary gain is likely to play an important role, but secondary gain is not simply confined to financial gain, it also includes gains made from avoidance of workplace stress and home and family duties. Other psychosocial factors, such as who is blamed for an injury (which may lead to retribution as a secondary gain) or the injured person’s educational and occupational status, may also influence this compensation effect. The literature review concludes that while the association between compensation and health after injury has been widely reported, the effect is inconsistent. These inconsistencies are due, at least in part, to differences in definitions of compensation (for example, claiming compensation versus using a lawyer), the use of different and poorly defined diagnoses (for example, back pain), a lack of control groups (many studies did not include uncompensated patients), and the lack of accounting for the many possible confounding factors (such as measures of injury severity or disease severity, and socio-economic and psychological factors). The literature review also highlighted the variety of different outcomes that had been used in previous studies, and the paucity of literature regarding the effect of compensation on general health outcomes. This thesis aims to explore the association between compensation status and health outcome after injury. It addresses many of the methodological issues of the previously published literature by, i selecting study populations of patients with measurable injuries, ii clearly defining and separating aspects of compensation status, iii including control groups of non-compensated patients with similar injuries iv allowing for a wide variety of possible confounders, and v using clearly defined outcome measures, concentrating on general health outcomes. Before commencing the clinical studies reported in Chapters Three and Four, a systematic review and meta-analysis was performed to quantify and analyse the effect of compensation on outcome after surgery. This allowed a clearly defined population of studies to be included, and was relevant to the thesis as the surgeries were performed as treatment of patients who had sustained injuries. The study, which is reported in Chapter Two, hypothesised that outcomes after surgery would be significantly worse for patients treated under compensation schemes. The study used the following data sources: Medline (1966 to 2003), Embase (1980 to 2003), CINAHL, Cochrane Controlled Trials Register, reference lists of retrieved articles and textbooks, and contact with experts in the field. The review included any trial of surgical intervention where compensation status was reported and results were compared according to that status, and no restrictions were placed on study design, language or publication date. Data extracted were study type, study quality, surgical procedure, outcome, country of origin, length and completeness of follow-up, and compensation type. Studies were selected by two unblinded independent reviewers, and data were extracted by two reviewers independently. Data were analysed using Cochrane Review Manager (version 4.2). Two hundred and eleven papers satisfied the inclusion criteria. Of these, 175 stated that the presence of compensation (worker's compensation with or without litigation) was associated with a worse outcome, 35 found no difference or did not describe a difference, and one paper described a benefit associated with compensation. A meta-analysis of 129 papers with available data (20,498 patients) revealed the summary odds ratio for an unsatisfactory outcome in compensated patients to be 3.79 (95% confidence interval 3.28 to 4.37, random effects model). Grouping studies by country, procedure, length of follow-up, completeness of follow-up, study type, and type of compensation showed the association to be consistent for all sub-groups. This study concludes that compensation status is associated with poor outcome after surgery, and that this effect is significant, clinically important and consistent. Therefore, the study hypothesis is accepted. However, as data were obtained from observational studies and were not homogeneous, the summary effect should be interpreted with caution. Determination of the mechanism for the association between compensation status and poor outcome, shown in the literature review (Chapter One) and the systematic review (Chapter Two) required further study. Two studies were designed to further explore this association and these are reported in Chapters Three and Four. The retrospective study reported in Chapter Three, the Major Trauma Outcome Study (MTOS), aimed to explore the association between physical, psychosocial, and compensation-related factors and general health after major physical trauma. The primary hypothesis predicted significantly poorer health outcomes in patients involved in pursuing compensation, allowing for possible confounders and interactions. The study also examined other health outcomes that are commonly associated with compensation, and examined patient satisfaction. Consecutive patients presenting to a regional trauma centre with major trauma (defined as an Injury Severity Score greater than 15) were surveyed between one and six years after their injury. The possible predictive factors measured were: general patient factors (age, gender, the presence of chronic illnesses, and the time since the injury), injury severity factors (injury severity score, admission to intensive care, and presence of a significant head injury), socio-economic factors (education level, household income, and employment status at the time of injury and at follow-up), and claim-related factors (whether a claim was pursued, the type of claim, whether the claim had settled, the time to settlement, the time since settlement, whether a lawyer was used, and who the patient blamed for the injury). Multiple linear regression was used to develop a model with general health (as measured by the physical and mental component summaries of the SF-36 General Health Survey) as the primary outcome. The secondary outcomes analysed were: neck pain, back pain, post-traumatic stress disorder, and patient satisfaction. On multivariate analysis, better physical health was significantly associated with increasing time since the injury, and with lower Injury Severity Scores. Regarding psychosocial factors, the education level and household income at the time of injury were not significantly associated with physical health, but pursuit of compensation, having an unsettled claim, and the use of a lawyer were strongly associated with poor physical health. Measures of injury severity or socio-economic status were not associated with mental health. However, the presence of chronic illnesses and having an unsettled compensation claim were strongly associated with poor mental health. Regarding the secondary outcomes, increasing neck pain and back pain were both significantly associated with lower education levels and the use of a lawyer, but not significantly associated with claiming compensation. The severity of symptoms related to post-traumatic stress disorder was not associated with measures of injury severity, but was significantly and independently associated with the use of a lawyer, having an unsettled compensation claim, and blaming others (not themselves) for the injury. The strongest predictor of patients’ dissatisfaction with their progress since the injury was having an unsettled compensation claim, and as with the other secondary outcomes, patient satisfaction was not significantly associated with injury severity factors. Factors relating to the compensation process were among the strongest predictors of poor health after major trauma, and were stronger predictors than measures of injury severity. The hypothesis that general physical and mental health would be poorer in patients involved in seeking compensation for their injury was accepted. This study concludes that the processes involved with claiming compensation after major trauma may contribute to poor health outcomes. The prospective study reported in Chapter Four, the Motor Vehicle Accident Outcome Study (MVAOS), aimed to explore the effect of compensation related factors on general health in patients suffering major fractures after motor vehicle accidents (MVAs). The study hypothesized that general health would be poorer in patients claiming compensation for their injuries. Patients presenting to 15 hospitals with one or more major fractures (any long bone fracture, or fracture of the pelvis, patella, calcaneus or talus) after a motor vehicle accident were invited to participate in this prospective study. Initial data was obtained from the patient and the treating doctors. Both the patients and treating surgeons were followed up with a final questionnaire at six months post injury. General factors (age, gender, treating hospital, country of birth, presence of chronic illnesses and job satisfaction), injury factors (mechanism of injury, number of fractures, and the presence of any non-orthopaedic injuries), socioeconomic factors (education level, income, and employment status), and compensation-related factors (whether a claim was made, the type of claim, whether a lawyer was used, and who was blamed for the injury) were used as explanatory variables. The primary outcome was general health as measured by the physical and mental component summaries of the SF-36 General Health Survey. The secondary outcomes were neck pain, back pain, and patients’ ratings of satisfaction with progress and of recovery. Multiple linear regression was used to develop predictive models for each outcome. Completed questionnaires were received from 232 (77.1%) of the 301 patients included in the study. Poor physical health at six months was strongly associated with increasing age, having more than one fracture, and using a lawyer, but not with pursuit of a compensation claim. Poor mental health was associated with using a lawyer and decreasing household income. Increasing neck pain and back pain were both associated with the use of a lawyer and with lower education levels. Higher patient satisfaction and patient-rated recovery were both strongly associated with blaming oneself for the injury, and neither were associated with pursuit of compensation. Although the use of a lawyer was a strong predictor of the primary outcomes, the pursuit of a compensation claim was not remotely associated with these outcomes, and therefore the study hypothesis was rejected. The studies reported in this thesis are compared in the final chapter, which concludes that poor health outcomes after injury are consistently and strongly associated with aspects of the compensation process, particularly the pursuit of a compensation claim, involvement of a lawyer, and having an unsettled claim. Compensation systems may be harmful to the patients that these systems were designed to benefit. Identification of the harmful features present in compensation systems my allow modification of these systems to improve patient outcomes.

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