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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.
441

Corporate governance, professionalisation and performance of IPO firms. The role of founders and venture capitalists.

Thiess, Rolf C. January 2010 (has links)
Combining agency theory and the resource-dependence perspective as well as signalling theory, this thesis examines the role venture capitalists (VCs) and founders play with respect to both structural board characteristics and board capital in terms of experience and prestige and whether these are linked to performance. It claims that VCs and founders shape the governance system of the firms going public and are influential in the professionalisation of the ventures especially in terms of human and social capital of its board of directors. It also argues that the board of directors represents a signal of firm quality in the initial public offering (IPO) market and should thus be linked to performance. Similarly, according to the venture capital certification hypothesis, being funded by VCs signals a firm¿s quality and potential. In order to assess these claims, this thesis employs a unique sample of matched venturecapital- backed and non-venture-capital-backed entrepreneurial IPOs that floated either on the London Stock Exchange¿s Official List or the Alternative Investment Market (AIM). Extending previous research this thesis employs more fine-grained measures and introduces new conceptually relevant variables in the analysis. The findings indicate that VCs and founders are influential in shaping corporate governance of IPO-stage ventures both from an agency and resource-provision perspective. Findings from the examination of governance and professionalisation characteristics with respect to IPO short-run performance (underpricing) indicate that it may the involvement of prestigious auditors that signal firm quality while a founder bias discount seems to exist. While evidence is found that VC involvement (and to a lesser extent director/board characteristics) is related to post-IPO market performance, this seems to depend on the time period following the IPO examined, whereas auditor prestige shows a positive association in all of these time periods. / Bradford University School of Management
442

An Examination of Two Control Processes That Operate Online During Target Directed Reaching

Grierson, Lawrence E. M. January 2008 (has links)
Examination of goal-directed aiming tasks has revealed that rapid, discrete human action is amendable to online control. This control affords humans a margin of error in movement planning and execution as well as a means of acquiring their goals when the body and/or the environment are extrinsically perturbed. For over a century, the models of online movement control that have best described the trajectories and outcomes of goal-directed reaches hold that these movements are composed of two distinct components. The first component moves the limb from its resting position towards the target. The second component is a corrective movement that is formed on the basis of a visual referencing of the moving limb and target positions. As such, the temporal and spatial characteristics of these discrete movement changes have been attributed to the limits of visual information processing. Furthermore, the absence of any discrete movement changes in the portions of movements outside of the temporal and spatial limits of vision led many investigators to conclude that first component impulses are ballistic and uncontrollable. However, recent studies involving environmental perturbation and within-subject trial-to-trial spatial variability analyses have evidenced that initial impulses are privy to online control. Because the corrections made early in movement impulses occur quicker than purely afferent visual information can be processed this form of control has been attributed to the use of forward anticipatory processes. The four studies presented here examine the nature of initial impulse control through kinematic analyses of reaches made to targets against various combinations of limb, target, and environment perturbations. This was done in order to evaluate anticipatory control's relationship with visually-regulated control and the relative influence the two processes have on the movement trajectory and performance outcome. The first study examined target-directed reaches made against illusory moving background and target relocation perturbations. The results showed the presence of early anticipatory and late visually-regulated control. Non-interactive main effects of the two perturbations on outcome accuracy revealed that the processes operate independently. The second study tested the applicability of an air discharging stylus as a tool for perturbing reach velocities. The results showed that the stylus effectively perturbed limb velocity and highlighted the presence of a limb forwarding response to either an advancing or hindering perturbation. The findings evidence the non-specific nature of anticipatory control responses. The third study examined reaches made against combinations of actual limb velocity and target position perturbations. The interactive effect of the two perturbations on reach trajectories and outcome accuracy indicated that the perturbations were salient enough to prompt parallel operation of the two control processes. Again, the control of initial movement portions was highlighted by non-specific responses to the perturbations. The fourth study examined reaches made against combinations of illusory and actual perturbations to both the anticipatory and visually-regulated control processes. Interestingly, performers withheld responses to the illusory perturbation unless they were also responding to an actual perturbation. This finding suggests that anticipatory control responses are biased during movement preparation. Furthermore, combined illusory and actual perturbations to target position had interactive effects on visually regulated control. Overall, the studies evidence that target-directed movements are mediated by two modes of control. There is an anticipatory mode of control that operates continuously and, given that reaches are made within the spatial and temporal limits of visual processing, there is also a feedback driven discrete mode of control that overlaps with the continuous mode. / Thesis / Doctor of Philosophy (PhD)
443

A Data Assimilation Scheme for the One-dimensional Shallow Water Equations

Khan, Ramsha January 2017 (has links)
For accurate prediction of tsunami wave propagation, information on the system of PDEs modelling its evolution and full initial and/or boundary data is required. However the latter is not generally fully available, and so the primary objective becomes to find an optimal estimate of these conditions, using available information. Data Assimilation is a methodology used to optimally integrate observed measurements into a mathematical model, to generate a better estimate of some control parameter, such as the initial condition of the wave, or the sea floor bathymetry. In this study, we considered the shallow water equations in both linear and non-linear form as an approximation for ocean wave propagation, and derived a data assimilation scheme based on the calculus of variations, the purpose of which is to optimise some distorted form of the initial condition to give a prediction closer to the exact initial data. We considered two possible forms of distortion, by adding noise to our initial wave, and by rescaling the wave amplitude. Multiple cases were analysed, with observations measured at different points in our spatial domain, as well as variations in the number of observation points. We found that the error between measurements and observation data was sufficiently minimised across all cases. A relationship was found between the number of measurement points and the error, dependent on the choice of where measurements were taken. In the linear case, since the wave form simply translates a fixed form, multiple measurement points did not necessarily provide more information. In the nonlinear case, because the waveform changes shape as it translates, adding more measurement points provides more information about the dynamics and the wave shape. This is reflected in the fact that in the nonlinear case adding more points gave a bigger decrease in error, and much closer convergence of the optimised guess for our initial condition to the exact initial wave profile. / Thesis / Master of Science (MSc) / In ocean wave modelling, information on the system dynamics and full initial and/or boundary data is required. When the latter is not fully available the primary objective is to find an optimal estimate of these conditions, using available information. Data Assimilation is a methodology used to optimally integrate observed measurements into a mathematical model, to generate a better estimate of some control parameter, such as the initial condition of the wave, or the sea floor bathymetry. In this study, we considered the shallow water equations in both linear and non-linear form as an approximation for ocean wave propagation, and derived a data assimilation scheme to optimise some distorted form of the initial condition to generate predictions converging to the exact initial data. The error between measurements and observation data was sufficiently minimised across all cases. A relationship was found between the number of measurement points and the error, dependent on the choice of where measurements were taken.
444

Inequalities related to Lech's conjecture and other problems in local and graded algebra

Cheng Meng (17591913) 07 December 2023 (has links)
<p dir="ltr">This thesis consists of four parts that study different topics in commutative algebra. The main results of the first part of the dissertation are in Chapter 3, which is based on the author’s paper [1]. Let R be a commutative Noetherian ring graded by a torsionfree abelian group G. We introduce the notion of G-graded irreducibility and prove that G-graded irreducibility is equivalent to irreducibility in the usual sense. This is a generalization of a result by Chen and Kim in the Z-graded case. We also discuss the concept of the index of reducibility and give an inequality for the indices of reducibility between any radical non-graded ideal and its largest graded subideal. The second topic is developed in Chapter 4 which is based on the author’s paper [2]. In this chapter, we prove that if P is a prime ideal of inside a polynomial ring S with dim S/P = r, and adjoining s general linear forms to the prime ideal changes the (r − s)-th Hilbert coefficient of the quotient ring by 1 and doesn’t change the 0th to (r − s − 1)-th Hilbert coefficients where s ≤ r, then the depth of S/P is n − s − 1. This criterion also tells us about possible restrictions on the generic initial ideal of a prime ideal inside a polynomial ring. The third part of the thesis is Chapter 5 which is based on the author’s paper [3]. Let R be a polynomial ring over a field. We introduce the concept of sequentially almost Cohen-Macaulay modules, describe the extremal rays of the cone of local cohomology tables of finitely generated graded R-modules which are sequentially almost Cohen-Macaulay, and also describe some cases when the local cohomology table of a module of dimension 3 has a nontrivial decomposition. The last part is Chapter 6 which is based on the author’s paper [4]. We introduce the notion of strongly Lech-independent ideals as a generalization of Lech-independent ideals defined by Lech and Hanes, and use this notion to derive inequalities on multiplicities of ideals. In particular, we prove a new case of Lech’s conjecture, namely, if (R, m) → (S, n) is a flat local extension of local rings with dim R = dim S, the completion of S is the completion of a standard graded ring over a field k with respect to the homogeneous maximal ideal, and the completion of mS is the completion of a homogeneous ideal, then e(R) ≤ e(S).</p>
445

Minimizing initial margin requirements using computational optimization

Ahlman Bohm, Jacob January 2023 (has links)
Trading contracts with future commitments requires posting a collateral, called initial margin requirement, to cover associated risks. Differences in estimating those risks and varying risk appetites can however lead to identical contracts having different initial margin requirements at different market places. This creates a potential for minimizing those requirements by reallocating contracts. The task of minimizing the requirement is identified as a black-box optimization problem with constraints. The aim of this project was to investigate that optimization problem, how it can best be tackled, and comparing different techniques for doing so. Based on the results and obstacles encountered along the way, some guidelines are then outlined to provide assistance for whomever is interested in solving this or similar problems. The project consisted both of a literature study to examine existing knowledge within the subject of optimization, and an implementation phase to empirically test how well that knowledge can be put to use in this case. During the latter various algorithms were tested in a number of different scenarios. Focus was put on practical aspects that could be important in a real situation, such as how much they could decrease the initial margin requirement, execution time, and ease of implementation. As part of the literature study, three algorithms were found which were evaluated further: simulated annealing, differential evolution, and particle swarm optimization. They all work without prior knowledge of the function to be optimized, and are thus suitable for black-box optimization. Results from the implementation part showed largely similar performance between all three algorithms, indicating that other aspects such as ease of implementation or parallelization potential can be more important to consider when choosing which one to use. They were all well able to optimize different portfolios in a number of different cases. However, in more complex situations they required much more time to do so, showing a potential need to speed up the process.
446

The accuracy of analyst ratings following the IPO quiet period

Lach, Patrick Adam 03 May 2008 (has links)
This study examines the long-run accuracy of analyst recommendations issued at the expiration of the initial public offering (IPO) quiet period and examines the relation between the Global Settlement, NYSE Rule 472, NASD Rule 2711, and analyst recommendations. It is expected that firms which receive positive recommendations will outperform the market and firms with neutral recommendations. In addition, it is expected that banks named in the Global Settlement will become more selective when issuing recommendations. This study examines firms engaging in IPOs from July 9, 2002 through December 31, 2005 and finds that analyst ratings have become more balanced following the Global Settlement, NYSE Rule 472, and NASD Rule 2711. When controlling for firm size, underpricing, rating heterogeneity, and analyst affiliation, firms which receive positive analyst ratings experience greater buy-and-hold abnormal returns than firms which do not. Furthermore, firms which receive multiple “buy” ratings outperform firms which receive only one “buy” rating when controlling for underpricing firm size, and the number of neutral ratings. Banks named in the Global Settlement appear to be more selective when issuing positive recommendations. Firms which receive a positive rating from a bank named in the Global Settlement outperform firms which receive a positive rating from a bank not named in the Global Settlement. Lastly, prior to the Global Settlement, it appears that sanctioned banks issued ratings one level higher than they should have. Firms which received positive ratings experienced neutral performance and firms which received natural ratings experienced negative performance. Since the Global Settlement, sanctioned banks appear to issue accurate ratings since positive ratings are associated with increased buy-and-hold abnormal returns and neutral ratings do not significantly impact firm performance.
447

The asymmetric information content of REIT IPOs

Steele, Dennis Franklin 11 December 2009 (has links)
This study examines asymmetric information content of REIT IPOs as compared to that of industrial IPOs matched by similar asset size, underwriter reputation ranking, and partial adjustment of the offer-price from the midpoint of the original file range. The asymmetric information level is proxied by the relative bid-ask spread (RELSPREAD), adverse selection component of Glosten and Harris (GH, 1988), and the adverse selection component of Lin, Sanger, and Booth (LSB, 1995). All three measures are estimated over 45- and 60-day windows. Using a sample of 78 equity REIT IPOs and 123 Industrial IPOs for the period of January 1, 1993 to December 31, 2007, the results indicate that REIT IPOs have less asymmetric information content as compared to mature industrial firms. All results control for leverage, beginning assets size, issue proceeds, underpricing, partial adjustment, number of IPOs within the same year, venture capital backing, underwriter reputation, average daily volume, average daily price, specialist’s inventory risk, and the turnover ratio. The results also control for the Nasdaq and NYSE rule change of minimum tick increments from 1/8th to 1/16th on June 2, 1997, and June 24, 1997, respectively. The findings provide strong support for the hypothesis that REIT IPOs have less asymmetric information content than non-REIT IPOs.
448

CONSOLIDATION ANALYSES OF GREATER CINCINNATI SOILS CINCINNATI, OHIO

DAYAL, NISHANT January 2006 (has links)
No description available.
449

Analysis and Control of the Boussinesq and Korteweg-de Vries Equations

Rivas, Ivonne January 2011 (has links)
No description available.
450

POWER AND THE ALLOCATION OF EQUITY AND CONTROL IN INITIAL PUBLIC OFFERINGS: A RESOURCE-DEPENDENCY APPROACH TO SIGNALING AND UNDERPRICING

Pearlstein, John Samuel January 2008 (has links)
The implication that first day returns of initial public offerings are a consequence of the imbalance of power between issuer and underwriter has been suggested more than it has been tested. An important tool in such an analysis has been missing. Using a resource contribution approach to bargaining power, measures of underwriter and issuer power are created. Significant results with both measures show that consistent with theory, underwriter power is positively associated with underpricing, while issuer power's association is negative. The underwriter power measure compares favorably in this study to Carter-Manaster's prestige measure. The theory presented also suggests that issuers and underwriters engage in a short-term cooperative agreement to bring critical resources to issuers to enhance their initial public offering. Contributed resources form the basis for each firms bargaining power which is strongest when setting the initial file price. Results show the importance of resource power on the distribution of proceeds and how power changes during the registration process. Finally this theory expands signaling theory and suggests that issuers under the influence and direction of their underwriter make pre-IPO organizational changes to send signals of quality to preemptively address investor's concerns. These pre-IPO gambits are intended to increase IPO proceeds, but come at a price. Theories of power are used to create a measure of the relative strength of these actors and find that making TMT changes significantly decreases underpricing. Although underwriter power is significantly associated with change, relative power does not reduce the amount of change signaled. / Business Administration

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