Diplomová práce se zabývá plánováním a analýzou experimentu. Je zde zkoumán vliv počtu centrálních bodů v plánu experimentu na nalezení významných faktorů procesu. Pro určení tohoto vlivu je použita metoda Monte Carlo, pomocí které hledáme míru nalezení významných faktorů procesu. Simulace experimentu je vytvořena v programu MATLAB, kde se především využívá Statistics toolbox pro generování náhodných čísel. V závěru je zhodnoceno a graficky ukázáno, jak je určení významnosti faktoru procesu závislé na počtu uvažovaných faktorů experimentu a na počtu měření v centrálním bodě.

Abstract  Course: NAA305 Bachelor Thesis in Economics 15 ECTS  University: Mälardalen University, School of Business, Society and Engineering, Västerås  Title: The effects of immigration on the income of native-born workers:  Evidence from Sweden Author: Arnold Schanzer-Larsen  Supervisor: Johan Lindén  Problem: Sweden has experienced a lot of immigration, and the phenomenon has received a great deal of attention in the public and political debate. There is, among other things, fear that immigration could be harmful for the labor market outcome of the receiving country. Researchers from a variety of countries have tried to address this issue by estimating the effect of immigration on the native wage of the receiving country. The results have varied strongly and no universal conclusion can be drawn. For what can be said about Sweden, there is no paper (of our knowledge) that has done any similar estimates. For that reason, it is of great importance that there is some research which could bring empirical evidence and shed light on the debate.  Purpose of the Research: The aim of the thesis is to quantitatively measure immigrations effect on the wage of native workers in Sweden. Methodology:  Conducting a panel study, observation of the average native income from 290 municipalities over 2011-2019 was collected. The effect was estimated using OLS regression technique and a fixed effect model.  Conclusion: From a 10% increase in the share of foreign-born within a municipality, led on average to a 2.89% increase in the native average income in that municipality.  Keywords: Immigration, Income, Wage, Unemployment rate, Panel study, Fixed effect model, Native, Labor market, The equilibrium model, Human capital, Skill-composition

Sweden was one of the few countries in the EU that in most cases decided to keep their elementary schools open during the COVID-19 pandemic. The purpose of this study was to investigate potential outcomes COVID-19 has had on students´ average merit scores as well as group-specific effects across genders and school types. To further estimate which factors might have also influenced students´ success, we decided to consider the share of higher educated parents and the municipality income for compulsory schools in our research. Using the fixed effects method, a few models were constructed to analyze the different effects. We found that in general, COVID-19 had a significant and positive effect on the average merit score of students across all elementary schools in Sweden, suggesting that there have been other factors influencing their academic performance. Furthermore, it was found that gender disparities and the share of higher educated parents have affected the average academic performance, whereas the municipality income for compulsory schools did not. Lastly, private schools were found to perform less positively compared to public schools.

<p>Postpartum depression has become a major public health concern for women within a specific time period after delivery. Depression is possibly associated with some risk factors such as socioeconomic status, social support, maternal mental and physical health, and history of anxiety. TOMIS III, funded by the Canadian Institutes of Health Research, is a prospective cohort to study the associations between delivery method and health and health resource utilization.</p> <p>Clinically, we investigated the associations between mode of delivery and outcome of postnatal depression, maternal and infant health, and we implied the risk predictors for outcomes by statistical methodology of marginal model with generalized estimating equations (GEE). Statistically, a variety of regression models, namely, generalized linear mixed effect model (GLMM), hierarchical generalized linear model (HGLM) and Bayesian hierarchical model were applied for this analysis and results were compared with GEEs. Some imputation strategies, namely, mean imputation, last observation carrying forward (LOCF), hot-deck imputation and multiple imputation were employed for handling missing values in this study.</p> <p>Analysis results demonstrated that there was no statistically significant association between mode of delivery and postpartum depression [OR 0.99, 95% CI (0.73, 1.34)]. However, the development of postpartum depression was found to be associated with low income, low mental and physical health functioning, lack of social support, the low number of unmet learning needs in hospital, and English or French spoken at home. Results were consistent for all regression models but GEE provided the best fit and an excellent discriminative ability. GEE models were constructed on different datasets imputed by mean, LOCF, hot-deck and multiple imputation, and LOCF was recommended to handle the missing data in this longitudinal study.</p> <p>Analyses on the outcome of maternal health and infant health stated that method of delivery had a statistically significant influence on maternal health but no significant impact on infant health. Risks of maternal health problems were associated with cesarean delivery, good/fair/poor infant health, low maternal mental and physical health functioning, lack of care for maternal mental health, and good/fair/poor health before pregnancy. Risks of infant health problems were associated with good/fair/poor maternal health before pregnancy and after discharge, inadequate care or help for infant health, fair/poor community services after discharge, low maternal mental health functioning, non-English or non-French spoken at home, and mothers born outside of Canada.</p> / Master of Science (MSc)

The hospitality industry has experienced significant changes in its competitive environment over the past 30 years, driven by the growth of alternative accommodations, the widespread use of the internet for searching and booking accommodations, and the adoption of asset-light business models. In this new competitive landscape, hospitality firms struggle to gain a competitive advantage, particularly as they lack rare and inimitable resources, which are considered crucial for achieving competitive advantage according to resource-based view literature. This dissertation explores three sets of strategies that enable hotel firms to attain a competitive edge despite their resources being non-rare and easily imitated by competitors. The first essay examines the potential for hotel firms to benefit from competitors' resources by co-locating with them. Although this strategy has been widely studied in organizational research, recent developments in the competitive market, such as internet adoption and the growth of short-term leases, have not been considered. Evidence suggests that internet adoption decreases the likelihood of low-level hotels entering markets with high-level hotels and negatively moderates the positive effect of branded hotels on independent hotels' performance, as well as nullifying the effect of low-level hotels on high-level hotels' performance. Additionally, short-term leases impact hotels' decisions and performance, as hotels tend to avoid co-locating with short-term leases with similar price points, and short-term leases can appropriate positive agglomeration externalities created by high-level hotels. The second essay investigates whether hotels can outperform competitors by gaining an advantage in resource appropriation through entering the market with a dual-branded hotel. Results indicate that a competitive advantage is achieved when at least one brand in the composition possesses better resources than competitors. Lastly, the third essay concentrates on the potential for hotels to leverage tacit knowledge transmission to increase the difficulty for competitors to imitate them. Findings reveal that the closer a hotel or short-term lease is to the nearest accommodation managed by the same hotel management company or host, the higher the chances of achieving a competitive advantage. Moreover, short-term leases can base their competitive advantage on idiosyncratic knowledge transferred from the platform, and they can compete in size with incumbent hotels if they have a high concentration of ownership in the market. / Doctor of Philosophy / The lodging industry has undergone numerous changes in the past 30 years, with the widespread adoption of the internet, the growth of the short-term lease market, and the implementation of asset-light strategies significantly impacting how hotels compete locally. This dissertation examines various market-entry strategies that can enable hotel firms to achieve a competitive advantage in local markets. The first essay explores the advantages of co-locating with competitors. Results indicate that previously identified benefits, such as reduced search costs for customers leading to higher performance for clustered competitors, have been diminished or nullified by the extensive use of the internet for searching and booking hotels. Independent hotels may still gain agglomeration advantages by co-locating with branded hotels, but the benefits are substantially reduced due to internet usage. Furthermore, the presence of different levels of short-term leases in the market affects hotels' entry patterns, which tend to diverge from short-term leases. Additionally, low-level short-term leases tend to capture agglomeration benefits created by high-level hotels, resulting in decreased performance for low-level hotels. The second essay investigates the optimal strategy for entering the market with a dual-branded hotel. Results show that, overall, adopting a vertically diversified strategy (i.e., where one of the two brands in the composition is of a higher class compared to the other) is preferable, with the higher class above the market's average class and the lower class below it. Conversely, the least effective strategy is to adopt a vertically diversified approach where both brands are below the market's average class. The third essay examines knowledge sharing among hotels and short-term leases managed by the same hotel management company or short-term lease host. Findings suggest that accommodations should be located near other properties managed by the same entity to facilitate operating knowledge transmission through face-to-face interactions, coordination among units, and the easy transfer of key personnel. Additionally, the study found that hotels should carefully consider entering a market with a high concentration of short-term lease ownership, as a higher concentration of short-term leases owned by the same host leads to lower hotels' RevPAR in the market.

The construction industry's two main certifications are Leadership in Energy and Environmental Design (LEED) and Energy Star. To achieve the triple bottom line of sustainability for these certifications, both certifications should make a positive impact individually as well as mutually, with their impact extending to the surrounding neighborhood. This research examined the spillover effect of LEED and/or Energy Star certified office buildings on the property values of other buildings in their neighborhood in Manhattan, New York City from an economic standpoint. The spatial analysis approach using the Geographic Information System and the statistical analysis approach based on the Hedonic Price Model and the Linear Mixed Effect Model were applied to identify the geographical distribution of LEED and/or Energy Star certified office buildings and their other buildings in their neighborhoods and analyze the impact of the former on the latter. The results were as follows: 1) There was a significant correlation between a LEED and/or Energy Star certified office building and the unit market values of its adjoining buildings through the unit market values of the certified office building, the LEED and/or Energy Star certification achievement, and the major features of LEED certification; 2) There was a varying spillover effect of the certified office building on the median unit market value of buildings depending on their proximities to a LEED and/or Energy Star certified office building. This research provides a firm foundation for further efforts to quantify the spillover effect of LEED and/or Energy Star certification on a neighborhood from an economic standpoint, thus supporting and encouraging growth in the local real estate market and benefitting not only the owners, developers, and investors of the certified office building but also the owners of neighboring buildings. / Ph. D.

1978年中國大陸在經濟上採取改革開放政策後，中國大陸克服資金不足、技術落後等問題，經濟快速成長、人民生活水準和人均生產總值皆大幅提升。但中國大陸內部卻面臨各地區經濟發展的程度有極大落差的困局。為此，中國大陸政府提出多項區域發展政策，期能撫平區域發展不均衡的差距，「西部大開發」即為其中之一，希望能藉此一舉改善西部目前發展上的弱勢。但是西部地區要脫離落後狀態朝向發展所需要之條件究竟為何?西部大開發政策所切入之角度是否正中西部所需?本文將由影響外商投資西部的決定性因素，來評估西部大開發政策之成效。透過1997至2005年外商對中國西部地區投資的追蹤資料，搭配固定效果模型的估計，分析影響外商至西部進行投資的趨勢及決定性因素為何，並以估計之結果檢視「西部大開發」政策是否切中西部發展所需，確實改善西部投資環境。 根據實證結果顯示，吸引外商至西部進行投資的決定性因素有四，分別為相對工資率、基礎建設、礦產資源，以及外資開放程度。其他的變數如市場大小、勞動力素質、國營企業比重、中央移轉性支付比例以及優惠政策等，皆未有顯著影響。 關鍵詞：西部大開發、外來直接投資、固定效果模型、決定因素 分類號：B23、C33、F21、R58 / Since China has adopted the so-called “open door policy” in 1978, it has overcame its shortage of economic investment and lagged technology by accepting foreign direct investment（FDI） and the “east-tilted” policy. Two decades later, while China enjoys its high economic growth rate, it has to solve the dilemma of keeping economy growing or balancing the regional disparity. Hence the China government has proposed the “Western Region Development” policy to facilitate the slow-growing economy in west China. Since FDI has played an important role in China economical development, the purpose of this study is to investigate the foreign direct investment in West China, and the flowing issue is using the results to evaluate the efficiency of Western Region Development policy, to see if the policy meet the need of western regional development. This study has based upon the panel data for western region during the period of 1997-2005 and fixed-effect model to investigate the determinants of FDI in West China. The result shows relative wage rate, infrastructure, mine resource, and openness to the rest of the world. Finally, in order to reduce the mistakes occurred in models and enable the study more rigorous, uses more methods to test the models and the result. Keywords: Western Region Development, Fixed-Effect Model, Foreign Direct Investment, Determinants JEL Classification: B23、C33、F21、R58

As linhas de distribuição de energia estão frequentemente expostas a sobretensões causadas por descargas atmosféricas diretas e indiretas. As formas de onda dessas sobretensões podem diferir bastante do impulso atmosférico normalizado utilizado em ensaios para verificação da adequação dos projetos das isolações dos equipamentos frente a sobretensões atmosféricas (1,2/ 50 µs). Diferentes modelos têm sido propostos para se estimar o desempenho das isolações frente a impulsos não normalizados, sendo o modelo do efeito disruptivo (disruptive effect model) um dos mais utilizados. Este trabalho visa avaliar o comportamento de isoladores de média tensão quando sujeitos a sobretensões atmosféricas bipolares oscilatórias. Simulações realizadas usando o \"Extended Rusck Model\"(ERM) e resultados de medições demonstram que a ocorrência de sobretensões bipolares oscilatórias em linhas de distribuição não é um fato raro, pois descargas atmosféricas podem, sob certas condições, induzir tensões com tais características. Modificações realizadas no circuito de um gerador de impulsos de alta tensão convencional permitiram a geração de tensões bipolares de três períodos distintos: 2,2 µs, 4,1 µs e 6,0 µs. Este trabalho investiga o comportamento de um típico isolador de porcelana tipo pino de 15 kV sujeito a um impulso bipolar, representativo de uma tensão induzida por um raio. Mostra-se que uma modificação no método proposto por Savadamuthu et al. para estimar a suportabilidade do isolamento de pequenos (alguns milímetros) sistemas de isolamento submetidos a tensões oscilantes bipolares leva a resultados promissores em termos de previsão da ocorrência de descargas no isolador de classe 15 kV. / Power lines are often exposed to surges caused by direct and indirect lightning. The waveforms of these overvoltages may differ significantly from the standard lightning impulse used in tests to verify the adequacy of equipment insulation designs against atmospheric overvoltages (1.2/50 µs). Different models have been proposed to estimate the performance of the insulation against non-normalized impulses, with the disruptive effect model being one of the most used. This work aims at evaluating the behavior of medium voltage insulators when subjected to bidirectionally oscillating voltages. Simulations run using the Extended Rusck Model (ERM) and measurement results show that the occurrence of bipolar oscillating overvoltages are not rare on power distribution lines, as lightning strokes can induce, under certain conditions, voltages with such characteristics. Modifications performed in the circuit of a conventional high voltage pulse generator allowed the generation of bipolar voltages of three distinct periods: 2.2 µs, 4.1 µs and 6.0 µs. This work investigates the behavior of a typical 15 kV pin-type porcelain insulator subjected to bipolar impulses representative of lightning-induced voltages. It is shown that a modification on the method proposed by Savadamuthu et al. to estimate the insulation strength of small (a few mm) insulation systems subjected to bipolar oscillating voltages leads to promising results in terms of predicting the occurrence of flashovers on the 15 kV insulator.

As linhas de distribuição de energia estão freqüentemente expostas a sobretensões causadas por descargas atmosféricas diretas e indiretas. As formas de onda dessas sobretensões têm uma faixa de variação muito ampla e podem diferir bastante do impulso atmosférico normalizado utilizado em ensaios para verificação da adequação dos projetos das isolações dos equipamentos frente a sobretensões atmosféricas (1,2 / 50 microssegundos). É fato conhecido que a suportabilidade das isolações depende não só da amplitude como da forma de onda das solicitações. Diferentes modelos têm sido propostos para se estimar o desempenho das isolações frente a impulsos não normalizados, sendo o modelo do efeito disruptivo (disruptive effect model) um dos mais utilizados. Existem, contudo, diferentes métodos de aplicação desse modelo, ou seja, diferentes formas de se estimar os parâmetros necessários para a sua aplicação. Este trabalho visa avaliar o comportamento dielétrico de isoladores de média tensão e analisar os principais métodos para estimativa da suportabilidade desses equipamentos frente a sobretensões atmosféricas com formas de onda diferentes da normalizada. Para essa avaliação foram realizados ensaios em um isolador tipo pino, de porcelana, com tensão nominal de 15 kV, nos quais foram utilizadas, além do impulso atmosférico normalizado, outras ondas selecionadas com base em resultados de medição e de cálculo. Modificações realizadas no circuito de um gerador de impulsos de alta tensão convencional permitiram a geração de tensões com formas de onda bastante semelhantes às de sobretensões induzidas por descargas atmosféricas tanto em linhas de tamanho natural como em experimentos realizados com modelo reduzido. São apresentados e discutidos os resultados dos ensaios de tensão disruptiva de impulso atmosférico a 50 % e as curvas tensão-tempo (U x t) obtidas para cada impulso, considerando ambas as polaridades. A avaliação dos métodos de aplicação do modelo do efeito disruptivo foi realizada com base em comparações entre as curvas tensão-tempo obtidas nos ensaios e as curvas previstas por cada modelo, para cada uma das ondas selecionadas. / Overhead distribution lines are often exposed to lightning overvoltages, whose waveshapes vary widely and can differ substantially from the standard impulse voltage waveshape used to test electric equipment insulation against lightning surges (1.2 / 50 microseconds wave). It is well known that the voltage withstand capability of insulation depends not only on the amplitude but also on the voltage waveshape. Different models have been proposed for predicting the strength of insulation subjected to impulses of non-standard waveshapes. One of the most commonly used is the \"disruptive effect model\". There are, however, different methods of applying this model, that is, different ways of estimating the parameters needed for its application. This thesis aims at evaluating the dielectric behavior of medium voltage insulators subjected to impulses of non-standard waveshapes, as well as at evaluating the main methods for predicting their dielectric strength against such impulses. For the analysis, tests were performed on a pin type porcelain insulator with rated voltage of 15 kV, using, besides the standard lightning impulse voltage waveshape, other s waveshapes selected based on the characteristics of measured and calculated lightning overvoltages. Modifications made to the circuit of a conventional impulse voltage generator allowed to obtain voltage waveshapes very similar to those of lightning-induced voltages measured in experiments conducted both in lines of natural size and in reduced model. The test results relative to the critical lightning impulse flashover voltage (U50) and the volt-time characteristics obtained for the positive and negative polarities of each waveshape are presented and discussed. The evaluation of the methods of determining the parameters of the disruptive effect model was based on comparisons between the volt-time curves obtained from the laboratory tests and those predicted by each method, for each of the selected voltage waveshapes.

處理類別型的資料時，常由於變異數與平均數間具有函數關係，因此資料呈現出來的變異程度會比預期的變異程度來的大，這種現象就稱為資料具有額外變異。一般的分析方法是利用廣義線性模型先作估計，再對估計之標準誤做調整。本文中將探討處理額外變異的另外兩種方法—準概似估計和隨機效果模型，並分別利用紡織原料與毒物學研究之資料作為範例來比較此兩種方法與前者的異同。 / Overdispersion is a common phenomenon in practice when modelling categorical data, and the scaled Pearson chi-square is usually used to measure it. In this study, we examine two other methods—the quasi-likelihood and the random-effect models. In addition, two examples are provided for illustration.