To further support and optimise the production of diving tables for the Armed Forces of Sweden, a research team has developed a new machine called IGUM (Inert Gas UndersökningsMaskin) which aims to measure how inert gas is taken up and exhaled. Due to the new design of machine, the goal of this thesis was to statistically validate its accuracy and verify its reliability.  In the first stage, a quality assurance of the linear position conversion key of IGUM in a steady and known gas flow was conducted. This was done by collecting and analysing data in 29 experiments followed by examination with ordinary least squares, hypothesis testing, analysis of variance, bootstrapping and Bayesian hierarchical modelling. Autocorrelation among the residuals were detected but concluded to not have an impact on the results due to the bootstrap analysis. The results showed an estimated conversion key equal to 1.276 ml/linear position which was statistically significant for all 29 experiments.  In the second stage, it was examined if and how well IGUM could detect small additions of gas in a dynamic flow. The breathing machine ANSTI was used to simulate the sinus pattern of a breathing human in 24 experiments where 3 additions of 30 ml of gas manually was added into the system. The results were analysed through sinusoidal regression where three dummy variables represented the three additions of gas in each experiment. To examine if IGUM detects 30 ml for each input, the previously statistically proven conversion key at 1.276ml/linear position was used. An attempt was made to remove the seasonal trend in the data, something that was not completely successful which could influence the estimations. The results showed that IGUM indeed can detect these small gas additions, where the amount detected showed some differences between dummies and experiments. This is most likely since not enough trend has been removed, rather than IGUM not working properly.

The climate changes have arguably been one of the main concerns during the last centuries.The largest contribution of the climate change derives from humanly created greenhouse gases.One third of the greenhouse gas emissions in Sweden comes from domestic transportation.This has led the government to set a taxation on fuels to reduce the carbon dioxide emissionsfrom transportation. The Swedish government has set a target of reducing the CO2 fromdomestic transportation by 70% of 2010th level by 2030 as a part of the long run target of zeronet emissions by 2045.This thesis aims to develop the knowledge about the relation between fuel taxation and carbonemissions from domestic car traveling in Sweden. One previous study has been conductedcovering the same problem. The previous study analyzed older data which creates theopportunity for this thesis to give updated results about the issue. This analysis is based ontime-series data from Sweden between 1990-2019. Regression models will be estimated usingordinary least squares (OLS) estimates to find the coefficient values. The results indicate anegative relationship between fuel taxation and carbon emission from cars in Sweden with a99% confidence level. An increase by the fuel tax by 1 SEK/liter would save approximately600 kilotons CO2 from domestic car traveling on a year. The value of the CO2 saved by anincrease of fuel tax by 1 SEK would be approximately 4 178 062 000 SEK. However, the resultshould not be interpreted as a recommendation for a policy. A more comprehensive analysisabout the effects of fuel taxation is needed to make decisions about whether the policy shouldbe implemented. The extended analysis should account for more ecological effects but also,economic, cultural, and social effects of the fuel tax. / Klimatkrisen är onekligen ett av de oftast debatterade problemen i modern tid. Klimatetsförändringar hotar flera arters överlevnadsmöjligheter, inte minst människan. Utsläpp avväxthusgaser är i dagsläget den största orsaken till de pågående klimatförändringarna. AvSveriges växthusgasutsläpp kommer en tredjedel från inrikestransporter. För att reduceraväxthusgaserna från inrikestransporter skattesätter staten drivmedel. Staten har en målsättningom att CO2 utsläppen från inrikestransporter ska minska med 70% av 2010 års nivå till år 2030.Detta är ett etappmål för att nå det långsiktiga målet om obefintliga nettoutsläpp avväxthusgaser år 2045.Denna studie avser att undersöka sambandet mellan drivmedelsskatten och koldioxidutsläppfrån inrikes biltransporter i Sverige. Liknande studier har genomförts tidigare, men då dessastudier analyserat äldre data kan denna studie ge en mer uppdaterad bild av problemet.Analysen bygger på tidsseriedata från Sverige mellan 1990–2019. Regressionsmodellerkommer att skattas med minsta kvadratmetoden (OLS) för att finna drivmedelsskattenssamband med koldioxidutsläppen från inrikes biltransporter. Resultatet visar att det finns ensignifikant negativ relation mellan drivmedelsskatten och koldioxidutsläpp från bilar i Sverigepå 99% konfidensnivå. En ökning av drivmedelsskatten med 1 krona per liter leder till enminskning av CO2 utsläpp från bilar med cirka 600 kiloton under ett år. Denna minskningmotsvarar ett värde av cirka 4 178 062 000 SEK. Resultatet bör dock inte tolkas som enrekommendation angående drivmedelsskatt. Vid beslutsfattande kring drivmedelsskatten bören mer omfattande analys genomföras. Den mer omfattande analysen bör innehålla flerekologiska effekter, men även ekonomiska, kulturella och sociala effekter avdrivmedelsskatten.

In this dissertation we introduce two variable selection procedures for multivariate responses. Our procedures are based on sufficient dimension reduction concepts and are model-free. In the first procedure we consider the dual marginal coordinate hypotheses, where the role of the predictor and the response is not important. Motivated by canonical correlation analysis (CCA), we propose a CCA-based test for the dual marginal coordinate hypotheses, and devise a joint backward selection algorithm for dual model-free variable selection. The second procedure is based on ordinary least squares (OLS). We derive and study the asymptotic properties of the OLS-based test under the normality assumption of the predictors as well as an asymmetry assumption. When these assumptions are violated, the asymptotic test with elliptical trimming and clustering is still valid with desirable numerical performances. A backward selection algorithm for the predictor is also provided for the OLS-based test. The performances of the proposed tests and the variable selection procedures are evaluated through synthetic examples and a real data analysis. / Statistics

The Forest Vegetation Simulator (FVS) is a growth and yield modeling system widely-used for predicting stand and tree-level attributes for management and planning applications in North American forests. The accuracy of FVS predictions for a range of tree and stand level attributes depends a great deal on the performance of the diameter increment model and its predictions of change in diameter at breast height (DBH) over time. To address the challenge of predicting growth in highly variable and geographically expansive forest systems, FVS was designed to include an internal calibration algorithm that makes use of growth observations, when available, from permanent inventory plots. The basic idea is that observed growth rates on a collection of remeasured trees are used to adjust or "calibrate" FVS diameter growth predictions. Therefore, DBH modeling was the focus of this investigation. Five methods were proposed for local calibration of individual tree DBH growth predictions and compared to two sets of results generated without calibration. Data from the US Forest Service's Forest Inventory and Analysis (FIA) program were used to test the methods for eleven widely-distributed forest tree species in Virginia. Two calibration approaches were based on median prediction errors from locally-observed DBH increments spanning a five year average time interval. Two were based on simple linear regression models fitted to the locally-observed prediction errors, and one method employed a mixed effects regression model with a random intercept term estimated from locally-observed DBH increments. Data witholding, specifically a leave-one-out cross-validation was used to compare results of the methods tested. Results showed that any of the calibration approaches tested in general led to improved accuracy of DBH growth predictions, with either of the median-based methods or regression based methods performing better than the random-effects-based approach. Equivalence testing showed that median or regression-based local calibration methods met error tolerances within ± 12% of observed DBH increments for all species with the random effects approach meeting a larger tolerance of ± 17%. These results showed improvement over uncalibrated models, which failed to meet tolerances as high as ± 30% for some species in a newly-fitted DBH growth model for Virginia, and as high as ± 170% for an existing model fitted to data from a much larger region of the Southeastern United States. Local calibration of regional DBH increment models provides an effective means of substantially reducing prediction errors when a relatively small set of observations are available from local sources such as permanent forest inventory plots, or the FIA database. / MS / The Forest Vegetation Simulator (FVS) is a growth and yield model widely-used for predicting stand dynamics, management and decision support in North American forests. Diameter increment is a major component in modeling tree growth. The system of integrated analytical tools in FVS is primarily based on the performance of the diameter increment model and the subsequent use of predicted in diameter at breast height (DBH) over time in forecasting tree attributes. To address the challenge of predicting growth in highly variable and geographically expansive forest systems, FVS was designed to include an internal calibration algorithm that makes use of growth observations, when available, from permanent inventory plots. The basic idea was that observed growth rates on a small set of remeasured trees are used to adjust or “calibrate” FVS growth predictions. The FVS internal calibration was the subject being investigated here. Five alternative methods were proposed attributed to a specific site or stand of interest and compared to two sets of results, which were based on median prediction errors, generated without calibration. Results illustrated that median-based methods or regression based methods performed better than the random-effects-based approach using independently observed growth data from Forest Service FIA re-measurements in Virginia. Local calibration of regional DBH increment models provides an effective means of substantially reducing prediction errors. The results of this study should also provide information to evaluate the efficiency of FVS calibration alternatives and a possible method for future implementation.

Thesis (MA (Political Science. International Studies))--University of Stellenbosch, 2009. / ENGLISH ABSTRACT: In an otherwise broad literature on civil conflict little attention has so far been paid to actual conflict violence and variation in severity. Existing work is also hampered by a reliance on a ‘closed polity’ model of the state, leading to disregard of the transnational dimensions of internal conflict, and by a dependence on over‐aggregated data. The present inquiry expands on the existing explanatory framework for variation in civil conflict severity by including transnational factors and characteristics of sub‐national actors. Data on conflict battle deaths are combined with recently available data on transnational ethnic linkages, transnational support and neighbouring conflict as well as other actor and country characteristics. Results from ordinary least squares regression analysis indicate that support for rebel groups from external non‐state actors increase conflict severity, while rebel presence in other states is associated with less severe conflicts. In addition, severity increases with duration but with a diminishing marginal return. Internal armed conflicts are less severe in democratic and ethnically polarised countries but rebel territorial control increases the level of violence. / AFRIKAANSE OPSOMMING: In die andersins omvangryke literatuur oor burgerlike konflik is daar tot op hede min aandag geskenk aan werklike konflikgeweld en variasie in felheid (vernietigende omvang). Bestaande werk word ook belemmer omdat dit staat maak op ’n model van die staat as ‘geslote regering’, wat lei tot verontagsaming van die transnasionale dimensies van interne konflik, en staat maak op oor‐geaggregeerde data. Hierdie ondersoek brei uit op die bestaande verklarende raamwerk vir variasie in felheid van burgerlike konflik deur transnasionale faktore en eienskappe van subnasionale deelnemers in te sluit. Data oor konflikgevegsterftes is gekombineer met onlangse data oor transnasionale etniese koppelings, transnasionale steun en naburige konflik, sowel as ander deelnemer‐ en landeienskappe. Resultate van gewone kleinstekwadrate‐regressie‐analise dui daarop dat steun aan rebellegroepe deur eksterne nie‐staatsdeelnemers konflikfelheid laat toeneem, terwyl rebelleteenwoordigheid in ander lande geassosieer word met minder fel konflikte. Felheid neem ook toe saam met duur maar met ’n afnemende marginale opbrengs. Interne gewapende konflikte is minder fel in demokratiese en etnies gepolariseerde lande, maar rebellebeheer oor grondgebied verhoog die vlak van geweld.

本研究欲觀察人口老化與所得分配之關係，檢視人口老化對於所得分配之影響，而文中主要分別從「內政部統計年報」、「家庭收支調查表」、「人力統計資源年報」以及各縣市統計要覽獲得各種解釋變數，建立出台灣1998年至2005年總計8年台灣各縣市之資料，並且以各縣市之吉尼係數為被解釋變數，採用最小平方法之方式藉此觀察台灣各縣市所得分配與人口老化之關係。 根據實證結果發現，人口老化與所得分配為顯著並且呈現正相關，亦即當人口老化更加嚴重時，將會導致較大的吉尼係數，造成所得不均之惡化。 其他解釋變數為顯著者分別有：平均每人可支配所得、平均每人可支配所得平方項、婦女勞動參與率以及各區域變數，且除了平均每人可支配所得平方項為負相關外，其餘皆與吉尼係數為正相關，其中所得方面之變數顯示出台灣中存在著Kuznets曲線；婦女勞動參與率的擴張則會導致所得分配更加惡化；中部、南部以及東部地區相對於北部區域來說其所得分配之狀況皆較不平均。而其他解釋變數如社會福利變數、教育變數以及工業變數所得之結果皆不顯著，顯示上述三個變數對台灣各縣市所得分配之影響在本研究中無法確定。 / This research discusses the relationship between aging population and income distribution, and examines how the aging population affects income distribution. The independent variables were acquired from the Statistical Yearbook of the Interior, The Survey of Family Income and Expenditure, the Statistical Yearbook of Labor Force and the Statistical Yearbook from each twenty-three counties and cities in Taiwan to construct a data set from 1998 to 2005. Using the ordinary least squares method and choosing the gini coefficient as a dependent variable to observe the relationship between income distribution and aging population. According to the result of the empirical study, we discover that the effect of aging population is significant and has a positive relationship with income distribution. Income inequality is worse when the aging population increases. Other significant independent variables are disposable income per person, the square of disposable income per person, female labor participation rate and the regional dummy variables. Besides the square of disposable income per person, all variables have a positive relationship with the gini coefficient. In addition, the variable of income shows that Kuznets curve appears in Taiwan. The expansion of the female labor participation will cause the income distribution to change into inequality. Also the north region has the worst income distribution in Taiwan. The results of the social welfare variable, the education variable and the industry variable are insignificant so that in this article we can not observe how the three variables effect the income distribution in Taiwan.

O Protocolo de Adesão à Organização Mundial do Comércio da China, assinado em dezembro de 2001, permitiu a outros países membros considerarem a China como uma economia \"não de mercado\" até o final de 2016. O objetivo deste trabalho é responder a seguinte pergunta: Pode o Reconhecimento de Economia de Mercado (REM) ser medido em seu compliance? O proxy utilizado parra o compliance foi o número de investigações antidumping iniciadas por país. A expectativa é que os países que reconhecem o status de economia de mercado da China iniciem menos investigações antidumping do que aqueles que ainda tratam a China como uma economia \"não de mercado\". Isso explicaria por que o governo chinês tem feito campanha desde 2001 para ganhar REM entre seus parceiros econômicos. A utilização de modelos de contagem demonstra que o REM teve um impacto positivo na redução do número de investigações antidumping contra produtos chineses. O atual desenvolvimento econômico da China depende muito de seu acesso a recursos energéticos, o que cada vez mais influencía mudanças nos Investimento Direto Estrangeiro (IDE) chinês com a finalidade de possibilitar o acesso a recursos que estão localizados no exterior. O objetivo deste trabalho é responder às seguintes perguntas: Em que medida a procura por recursos energéticos afetou os IDE entre 2005 e 2012? Essa procura foi sensível à locação geográfica dos recursos? Os dados sobre IDE chineses foram obtidos do China Global Investment Tracker, e utilizaram-se determinantes domésticos de IDE, testados empiricamente na literatura existente, para medir o impacto da produção de energia do país anfitrião na alocação de investimentos. Ao aplicar MCO e um modelo com lag espacial em uma amostra de 92 países demostrou-se que os recursos energéticos do país anfitrião foram o principal motor da IDE chinesa, e que não houve sensibilidade geográfica aos recursos. / China´s Protocol of Accession to the World Trade Organization, signed on December 2001, allowed other country members to consider China as a Non Market Economy (NME) until the end of 2016. The aim of this paper is to answer the following question: Can the Market Economy Status (MES) Recognition be measured in its compliance? The proxy used for that compliance was the number of antidumping investigations initiated per country. The expectation is that countries recognizing Chinese MES would initiate fewer antidumping investigations than countries still treating China as a Non Market Economy. This would explain why the Chinese Government has been campaigning vigorously since 2001 to gain MES among its economic partners. Using count-models we demonstrate that MES had a positive impact in reducing the number of antidumping investigations against Chinese products. China´s current economic development depends heavily on its access to energetic resources, and it is increasingly shaping Chinese Outward Foreign Direct Investment (OFDI) in a quest for gaining access to resources that are located abroad. The aim of this paper is to answer the two following questions: How much did the Chinese global quest for energy drive its OFDI between 2005 and 2012? Has the quest for energy been sensitive to the geographical location of the resources? Data on Chinese OFDI was retrieved from the China Global Investment Tracker, and we used diverse Host-Countries determinants of OFDI tested before in the literature and measured the impact of Host-Country energy production in the allocation of investments. Using OLS and a Spatial Lagged Model we demonstrate that energetic resources were the main driver of Chinese OFDI in 92 host countries during the studied period, and that there was no sensitivity to the geographical location of the resources.

Parameter estimation techniques have been successfully and extensively applied to deterministic models based on ordinary differential equations but are in early development for stochastic models. In this thesis, we first investigate using parameter estimation techniques for a deterministic model to approximate parameters in a corresponding stochastic model. The basis behind this approach lies in the Kurtz limit theorem which implies that for large populations, the realizations of the stochastic model converge to the deterministic model. We show for two example models that this approach often fails to estimate parameters well when the population size is small. We then develop a new method, the MCR method, which is unique to stochastic models and provides significantly better estimates and smaller confidence intervals for parameter values. Initial analysis of the new MCR method indicates that this method might be a viable method for parameter estimation for continuous time Markov chain models.

Aerodynamic parameter estimation from closed loop data has been developed as another research area since control and stability augmentation systems have been mandatory for aircrafts. This thesis focuses on aerodynamic parameter estimation of an air to ground missile from closed loop data using separate surface excitations. A design procedure is proposed for designing separate surface excitations. The effect of excitations signals to the system is also analyzed by examining autopilot disturbance rejection performance. Aerodynamic parameters are estimated using two different estimation techniques which are ordinary least squares and complex linear regression. The results are compared with each other and with the aerodynamic database. An application of the studied techniques to a real system is also given to validate that they are directly applicable to real life.

Aerodynamic parameter estimation from closed loop data has been developed as another research area since control and stability augmentation systems have been mandatory for aircrafts. This thesis focuses on aerodynamic parameter estimation of an air to ground missile from closed loop data using separate surface excitations. A design procedure is proposed for designing separate surface excitations. The effect of excitations signals to the system is also analyzed by examining autopilot disturbance rejection performance. Aerodynamic parameters are estimated using two different estimation techniques which are ordinary least squares and complex linear regression. The results are compared with each other and with the aerodynamic database. An application of the studied techniques to a real system is also given to validate that they are directly applicable to real life.