Academic literature on the topic 'IPW'

The mountainous western Virginia is the source of the headwater streams for the New, the Roanoke, and the James rivers. The region is prone to flash flooding, typically the result of localized precipitation. Fortunately, within the region, there is an efficient system of instruments for real-time data gathering with IFLOWS (Integrated Flood Observing and Warning System) gages, WSR-88D Doppler radar, and high precision GPS (Global Positioning System) receiver. The focus of this research is to combine the measurements from these various sensors in an algorithmic framework to determine the flash flood magnitude. It has been found that the trend in the GPS signals serves as a precursor for rain events with a lead-time of 30 minutes to 2 hours. The methodology proposed herein takes advantage of this lead-time as the trigger to initiate alert related calculations. It is shown here that the sum of the rates of change of total cloud water, water vapor contents and logarithmic profiles of partial pressure of dry air and temperature in an atmospheric column is equal to the rain rate. The total water content is measurable as the profiles of integrated precipitable water (IPW) from the GPS, the vertically integrated liquid (VIL) from the radar (representing different phases of the atmospheric water) and the pressure and temperature profiles are available. An example problem is presented illustrating the involving the calculations.<br>Master of Science

Multicollinearity can be present in the propensity score model when estimating average treatment effects (ATEs). In this thesis, logistic ridge regression (LRR) and principal components logistic regression (PCLR) are evaluated as an alternative to ML estimation of the propensity score model. ATE estimators based on weighting (IPW), matching and stratification are assessed in a Monte Carlo simulation study to evaluate LRR and PCLR. Further, an empirical example of using LRR and PCLR on real data under multicollinearity is provided. Results from the simulation study reveal that under multicollinearity and in small samples, the use of LRR reduces bias in the matching estimator, compared to ML. In large samples PCLR yields lowest bias, and typically was found to have the lowest MSE in all estimators. PCLR matched ML in bias under IPW estimation and in some cases had lower bias. The stratification estimator was heavily biased compared to matching and IPW but both bias and MSE improved as PCLR was applied, and for some cases under LRR. The specification with PCLR in the empirical example was usually most sensitive as a strongly correlated covariate was included in the propensity score model.

Mestrado em Econometria Aplicada e Previsão<br>Esta dissertação analiza técnicas de correção do efeito do enviesamento que pode ocorrer no caso dos dados utilizados apresentarem valores em falta. Tais técnicas serão aplicadas a um modelo económico para caracterização da margem líquida de juros (MLJ) bancária, utilizando dados provinientes 15 países que pertencem ao sistema bancário da União Europeia (UE15). As variáveis que caracterizam os bancos são observados entre de 2004 e 2010. E são escolhidas seguindo Valverde et al. (2007). Adicionalmente aos regressores são acrescentadas algumas variáveis macroeconómicas. A seleção proviniente da falta de alguns valores para os regressores é tratada através da ponderação probabilistica inversa. Os ponderadores são aplicados a estimadores GMM para um modelo de dados de painel dinámico.<br>This thesis discusses techniques to correct for the potentially biasing effects of missing data. We apply the techniques on an economic model that explains the Net Interest margin (NIM) of banks, using data from 15 countries that are part of the European Union (EU15) banking system. The variables that describe banks cover the period 2004 and 2010. We use the variables that were also used in Carbó-Valverde and Fernndez (2007). In addition, also macroeconomic variables are used as regressors. The selection that occurs as a consequence of missing values in these regressor variables is dealt with by means of Inverse Probability Weighting (IPW) techniques. The weights are applied to a GMM estimator for a dynamic panel data model that would have been consistent in the absence of missing data.

Internet Protocol Telephony (IPT), also known as Voice over Internet Protocol (VoIP), has evolved from a niche technology to one that is adopted fairly well in developed countries. The aim of this research report was to determine whether IPT will also be a success in the Republic of South Africa, which is one of many developing countries. The technology was analysed and it was found that cost reduction, increased productivity and enhanced applications were the most valuable benefits the technology could offer. Particular interesting impediments of the technology were discovered and it was found that there existed both hard issues like security and quality problems, as well as softer issues like internal politics, that could hinder the global success of the technology. The adoption rate of South Africa was compared to that of industrial countries and it was found that South African organisations overall posed a wait-and-see attitude towards IPT. Various implementation models were discussed and it was found that a hybrid approach would be the most viable option for local organisations. The South African environment were analysed and it was discovered that the biggest obstacle for success in South Africa was the regulatory environment. But it was also found that the environment would soon change and that competitors, including Black Economic Empowerment companies, should use the opportunities available. Social factors like HIV/AIDS and theft as well as economic factors like the exchange rate could hamper the competitiveness of local companies using IPT. IPT technology can only be a success in South Africa if it is intensely supported by Government, implemented in the correct manner and adopted aggressively by the local market.<br>Dissertation (MBA)--University of Pretoria, 2006.<br>Graduate School of Management<br>unrestricted

Dissertação de Mestrado em Design, com a especialização em Produto apresentada na Faculdade de Arquitetura da Universidade de Lisboa para obtenção do grau de Mestre.<br>Cerca de 80% da informação que o ser humano recebe é através da visão. Para pessoas cegas e com perda de visão severa a mais simples atividade do dia-a-dia pode tornar-se num desafio.
A identificação de produtos é um problema comum para estas pessoas, principalmente produtos alimentares, sempre que a pessoa necessita de ir às compras, na despensa em casa ou em cada refeição do dia em que é necessário cozinhar. Para ajudar a população portadora de deficiência visual, a enfrentar este problema, esta dissertação tem como objeto de estudo o desenvolvimento de um equipamento/dispositivo que resolva este obstáculo de maneira a dar-lhe mais autonomia. Durante o desenvolvimento deste estudo foi importante salientar temas como o “Design Inclusivo”, o “Interação Produto/ Utilizador”, “Deficiência Visual” e a “Identificação de produtos”. Em termos metodológicos foi realizada, nesta dissertação, uma investigação de natureza mista assente em métodos intervencionistas e não-intervencionistas. Elaborou-se uma revisão da literatura, com o objetivo de reunir as bases teóricas das áreas de estudo; recorreu- se a uma análise de casos de estudo; fez-se um levantamento dos dispositivos existentes no mercado recorrendo a um estudo de casos; foram realizadas conversas informais, mas essenciais ao desenvolvimento do projeto e ainda se concretizou uma entrevista exploratória com um grupo de amostragem. Aplicando ainda uma metodologia não-intervencionista, foram feitos inquéritos por entrevista ao grupo de amostragem, colaborador e especialista, com o intuito de perceber que alterações seriam necessárias para a evolução do projeto. Simultaneamente, e numa vertente mais prática de investigação ativa, foram criados diversos modelos-teste do dispositivo, em que o último modelo, mais próximo daquilo que seria o dispositivo na realidade, foi utilizado para a realização de uma avaliação e simulação da utilização do mesmo, com o grupo de amostragem. Deste modo, espera-se que este processo de investigação permita mostrar a importância de uma melhor maneira de identificar produtos alimentares que facilite a rotina diária das pessoas portadoras de de ciência visual, melhorando consequentemente a sua qualidade de vida.<br>ABSTRACT: About 80% of the information that the human being receives is through vision. For blind people and with severe vision loss, the simplest day-today activity can become a challenge.
Product identification is a common problem for these people, especially food products, whenever they need to go shopping, in the pantry at home or at each meal of the day when it is necessary to cook. To help the population with visual imparment dealing with this problem, this dissertation has as object of study, the development of an equipment/device that can solve this problem in order to give more autonomy. During the development of this study it was important to highlight themes such as “Inclusive Design”, “Product-User Interaction”, “Visual Impairment” and “Product Identification”.
In methodological terms it was made, in this dissertation, a mixed nature investigation with interventionist and non-interventionist methods. A review of the literature was made, aiming to gather the theoretical bases of the study areas; It was made an analysis of study cases; a survey of the existing devices on the market was done using case studies; informal conversations were carried out, but they were essential to the development of the Project, it was also done an exploratory interview with a sampling group. Applying a non- interventionist methodology, were elaborated surveys by interview to the sampling group, a collaborator and a specialist, in order to understand what changes would be necessary for the evolution of the project. Simultaneously, and in a more practical eld of active investigation, several test models of the device were created, in which the last one, closer to what the device would actually be, was used to carry out an evaluation and simulation of its use, with the sampling group. Therefore, is expected that this process of investigation shows the importance of a better way to identify food products that facilitates the daily routine of blind or visually impaired people, giving them the desired autonomy.<br>N/A

The thesis aims to apply the theoretical approach of IPOs and financial services firm valuation on the Czech subsidiary of KBC: ČSOB. The theoretical part reviews the process of IPO with typical features of IPOs, and the pricing of IPO is discussed with the focus on theory of banks valuation. The empirical part of the thesis provides a financial analysis of the ČSOB, business plan and the valuation of the bank as of 30 September 2010 with the price of the actual IPO. This part aims at practical application of the theory of IPO and valuation. Al in all, the aim of the thesis is to apply theoretical knowledge of the IPOs on the practical case of ČSOB. Various analyses such as of KBC, ČSOB, Czech banking market, development of IPOs in CEE are used in order to apply and determine the reasons for the IPO, its timing, price and potential structure of investors.