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5663 Uppsatser om First difference model - Sida 1 av 378

Utveckling och utvördering av statistiska metoder för att öka träffsäkerheten hos lokala vindprognoser

Wind is used as an energy source all over the world. To be able to use this effectively, there is a need for as good forecasts and forecast models as possible. One of these models is Coupled Ocean/Atmosphere Mesoscale Prediction System (COAMPS®) that is used to calculate short time forecasts. This model is used here to calculate wind speeds at two different areas in Västra Götaland, Bengtsfors and Vänersborg. There are also wind measurements with SODAR stations for these areas.

Valutamarknadens effektivitet - En studie av växelkurser utifrån UIP med förväntningar

This essay discusses and evaluates the international currency market in regards to efficiency. To prove the theory that, the difference between expected and actual exchange rates is explained by the difference in expected and actual interest rates and the difference in expected and actual inflation between countries, a model was developed. This model was inspired by the paper of Sebastian Edwards (1982), and is based on three theories; UIP, IS/LM and the Efficient Markets Hypothesis. The model uses 16 regressions estimated from three pairs of curriencies: $/SEK, £/SEK and ?/SEK.

Kan vi prata om det? Deliberativ demokrati, mångfald och politisk kamp

In recent years the liberal representative democracy has been subject of a substantial critique because of its inability to accommodate difference and createa genuinely democratic political process. One such critique comes from the theory of deliberative democracy. Supporters of deliberative democracy try to promote a model of democracy that take its vantage point in free and equal deliberationbetween all relevant actors in a political community. This model has with some success opposed the aggregative model of democracy, and in important ways turned the attention to the potential of deliberative processes.However, the deliberative model is still somewhat underdeveloped when it comes to issues of diversity and difference. This essay deals with such deficiencies by analysing deliberative democracy in the light of the critiquelaunched by difference- and radical democrats.

Prognostisering av räntabilitet på eget kapital - En jämförelsestudie av tre regressionsmodellers prognosförmåga applicerat på svenska data

A multivariate cross-sectional model is used in this thesis to proxy for expected earnings and to estimate return on equity for 214 companies over the period 2009-2013, using Swedish data. The model, which has never been tested on Swedish data before, is first confirmed to function as a forecasting model for expected return. Furthermore, the model is evaluated through a comparison with two univariate models based on the assumption that return on equity follows a mean reversion process. Forecast accuracy is calculated as the difference of estimated returns and actual returns. The results show that the univariate models' forecasts are superior to the multivariate model's..

Simulering av filtrerade skärmfärger

This report present a working model for simulation of what happens to colors displayed on screens when they are observed through optical filters. The results of the model can be used to visually, on one screen, simulate another screen with an applied optical filter. The model can also produce CIE color difference values for the simulated screen colors. The model is data driven and requires spectral measurements for at least the screen to be simulated and the physical filters that will be used. The model is divided into three separate modules or steps where each of the modules can be easily replaced by alternative implementations or solutions.

Den moderna kommunikationen : En rapport om instant messaging och hur det används av unga vuxna studenter.

This paper describes the development of a simulation model for the ambulance flow in the Västra Götalands-region of Sweden, and an analysis tool for the output of the simulation model. The aim of the simulation model was to be able to evaluate the outcome from changes in the ambulance operations, such as a reorganization of ambulances or an increase in intensity of the ambulance calls. This evaluation is meant to serve as decision support for the strategic planning of the ambulance operations. The analysis tool was developed to visualize the abundant geographical data produced by the simulation model in a meaningful way. The simulation model was validated against historical data which showed that the dispatch time for the highest prioritized ambulance calls corresponds well with historical data.

Avancerad scenarioanalys för ambulansplanering

This paper describes the development of a simulation model for the ambulance flow in the Västra Götalands-region of Sweden, and an analysis tool for the output of the simulation model. The aim of the simulation model was to be able to evaluate the outcome from changes in the ambulance operations, such as a reorganization of ambulances or an increase in intensity of the ambulance calls. This evaluation is meant to serve as decision support for the strategic planning of the ambulance operations. The analysis tool was developed to visualize the abundant geographical data produced by the simulation model in a meaningful way. The simulation model was validated against historical data which showed that the dispatch time for the highest prioritized ambulance calls corresponds well with historical data.

Alternativ till fortsatt elektrisk generering i Olidan

In this thesis a possible cost effective runner change of some of the units in the hydroelectric power station Olidan is investigated. The possibility to drive a unit at the same efficiency point through a change of the turbine shaft speed and the rate of discharge is tested. Furthermore the theories behind model testing, determination of efficiency increase from model to prototype and efficiency measurements shall be discussed and analyzed with Olidan as a starting point.A predicted curve has been built on information from model tests and field measurements on the existing runners and runner data from the test of the new model. The predicted curve shows the difference in efficiency between an existing runner and a modern one. It is the difference in efficiency that is used in the calculations that are to show whether changing to a pair of new runners will be cost effective or not.

Price adjustment and vacancies on theStockholm market ? Estimation of rent levelsdue to office-allocations

The Stockholm office market segment have for a long time been considered a safe havenwhen it comes to withstand negative turmoil in the form of rental compression due toeconomic fluctuation, especially in the CBD demographic. Recently however, a large numberof banks and institutions, amounting to some 200000 square meters, have decided to relocateto more peripheral locations with the aim of cost reductions on rent. This mass exodus isstudied with focus on rental dynamics as the result of increased vacancies. Other variables arestock changes and employment. The method is econometric combined with an interviewseries.

Modell för fördelning av kostnader i lager

Distrilux International AB, a company within the Electrolux-group, works among other things with storing of products from other companies in the Electrolux-group. This rapport contains a cost analysis of the two Distrilux warehouses in Motala and Mariestad. The company offers five services in these warehouses, in-loading of products from a local factory and from external factories, storing, out-loading of products to Sweden (domestic) and for export. Since there has been some hesitation of the accuracy of the price-model of today, a master's thesis has been advertised. The purpose of the thesis has been to investigate the agreement of the price-model of today and the apportionment of the costing in warehouses.The main problem is to determine which activities is to be considered important in the price-model.

Produktivitet och kvalitet vid stickvägs- respektive beståndsgående förstagallring :

Nowadays the majority of the thinnings made in Swedish forests are done by machines, harvesters and forwarders. The most common model in thinning with a harvester is strip-road operated thinning and stand-operated thinning with one intermediate passage between the strip-roads. This study is a time study with some quality follow ups on a strip-road operated thinning model, a stand-operated thinning model with one intermediate passage between the strip-roads and a stand-operated thinning model with two intermediate passages between the strip-roads. The machines in the study were a small harvester (Forestline MPM C90) and a medium sized forwarder (Timberjack 1110). The study was made in Litsnäset outside the city of Östersund in Sweden and was made during the autumn 2007. In a lodgepole pine stand six study units (0,6 ha) were thinned with the three different models, two study units per model.

Värdeförändring på butiksfastigheter och makroekonomiska variabler - en ekonometrisk studie av samvariation

The purpose of this Bachelor thesis in Economics at Lund University is to try to establish the correlation between the value change of retail real estate buildings in Sweden and macro economic variables. The principal method is the multiple regression model and it is used to estimate the basic model. The basic model is enhanced by estimating some 30 models and the result is two good models. The difference between the basic model and the two better models are small but important. In the lagged basic model, the same variables are used as in the basic model but with different time lags.

Protein i korn : En torkstudie utförd med etablerade analysmetoder på tre kornsorter

A study was performed to evaluate whether established methods of analysis of protein content in barley (Kjeldahl, Dumas, or NIT (short for Near Infrared Transmittance)) gives different results for wet and dried barley. This was carried out because there are concerns regarding the well-worn NIT prediction model giving different results for these conditions and that such an error causes significant price fluctuations on the market. By performing analyses of samples, both before and after drying, of the three different barley varieties Tipple, Prestige, and Quench, with all the techniques, data was obtained that could be analyzed statistically. The study showed that the NIT prediction model gives results for wet barley that is about 0.29 percentage points higher compared to dried barley. This difference was also statistically significant when a t-test was performed.

En studie om införandet av expected loss model : - En mer tillförlitlig och relevant metod för nedskrivning av finansiella tillgångar?

Accounting has been critized for being one of the leading factors in the latest financial crisis. One of the primary problem areas was identified as delayed recogonition of losses on financial instruments. Consequently, a new impairment model is being developed and is to be namned expected loss model. The difference from the present model, incurred loss model, is that it takes losses into consideration on an much earlier level. Even though the model may be theoretically feasible, in practice it may implicate a number of issues.

Datormodellering av en värmelagrande betongväggs inverkan på det termiska klimatet i ett växthus

This report describes the building of a computer model that makes it possible to simulate the thermal climate in a greenhouse. The computer model is built on the physical theory of heat exchange that occur in a greenhouse, such as radiation and convective heat exchange. The model also includes the heat storage that is active in a greenhouse.The computer model is used to simulate the thermal climate in a greenhouse under three periods, winter, spring and summer. It also investigates which effect a concrete wall has on the thermal climate in a greenhouse. The purpose of putting a concrete wall in the greenhouse model is to investigate the possibility to store heat during the day and then use this heat when the temperature drops during the night.The result from the simulations shows that a concrete wall levels the big difference in temperature that normally occurs under a day in a greenhouse.

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