Le modèle cosmologique standard possède plusieurs lacunes pour une description pertinente de l’évolution de notre univers et de ses constituants. Tout d’abord, il laisse en suspens l’explication de l’origine de la matière noire et de l’énergie sombre. Ces composants, introduits ad hoc afin de satisfaire aux observations, représentent ensemble environ 95% du contenu en énergie de l’univers. Un second problème concerne l’indépendance d’échelle du modèle : quel que soit l’échelle du système considéré, il est attendu une dynamique et une géométrie identiques. Il est possible de se détourner du modèle standard et de s’intéresser à des cosmologies inhomogènes et à leur évolution moyenne. Selon ce formalisme, les inhomogénéités au sein d’une échelle influencent globalement la dynamique de cette dernière par un effet dit de rétroaction. Cette démarche très riche propose également une explication élégante au problème des constituants sombres : tous deux apparaissent comme une manifestation effective des inhomogénéités de distributions de matière et de géométrie. Cette thèse s’intéresse aux propriétés des modèles inhomogènes moyennés en relativité générale. Nous proposons dans un premier temps de décrire le comportement global des inhomogénéités selon une évolution de Chaplygin, et selon une évolution de Ginzburg-Landau. Nous montrons également l’instabilité gravitationnelle globale des solutions de Friedmann-Lemaître-Robertson-Walker. Cette classe de solutions est connue comme étant localement instable sous l’introduction de perturbations ; ici nous montrons qualitativement qu’elle ne fournit pas, en général, une approximation correcte en tant que fond physique. Nous présentons finalement une nouvelle théorie relativiste perturbative, pour laquelle les inhomogénéités scalaires évoluent autour d’un fond général, et non plus autour d’un fond de Friedmann-Lemaître-Robertson-Walker pré-défini. Cette nouvelle étude étend l’applicabilité des cosmologies inhomogènes, et pourrait éventuellement expliquer la formation des grandes structures sans recours à l’énergie noire / The standard cosmological model possesses some shortcomings for a relevent description of our universe and its constituents. First, it leaves in suspense the explanation of the origin of dark matter and dark energy. These components, introduced ad hoc in order to fit the observations, represent about 95% of the total energy. A second issue concerns the scale-independence of the model: whatever the scale of the considered system, it is expected identical dynamics and geometry. It is advisable to abandon the standard model and to focus on inhomogeneous cosmologies, and their average evolution. According to this formalism, inhomogeneities within a chosen scale globally impact on the dynamics of this latter through a so-called backreaction effect. This very rich approach also proposes an elegant explanation for the problem of the dark constituents: both stand for an effective manifestation of the inhomogeneities in the distributions of matter and geometry. This thesis focusses on the properties of averaged inhomogeneous models in general relativity. We first propose to describe the global behaviour of inhomogeneities according to a Chaplygin evolution, and according to a Ginzburg-Landau evolution. We also show the global gravitational instability of Friedmann-Lemaître-Robertson-Walker solutions. This class of solutions is already known to be locally gravitationaly unstable under the introduction of perturbations; here we show qualitatively that it does not furnish, in general, a good approximation as a physical background. We finally present a new relativistic perturbative scheme, in which scalar inhomogeneities evolve on a general background rather than on a pre-defined Friedmann-Lemaître-Robertson-Walker background. This new study extends the framework of application for inhomogeneous cosmologies, and may possibly explain the large-scale structure formation without the need for dark energy

Since the 1970s, the international economic system has become prone to the volatility and undue effects associated with booms and busts. This forty year period spanning the present has exhibited restrained growth and repressive economic development. Critical changes to the system are presented by the transition from "Fordism" to the post 1970s neoliberal regime and the globalization of world markets. Underpinning this transformation is an ideological shift towards free market capitalism and the adoption of "reduced form" market models. These "reduced form" models appear to hinder economic sustainability as their grounding in economics fails to account for real economic activity. This thesis aims to provide a more holistic perception of sustainability, one that provides a sound basis on which to develop sustainable economic policy. The Regulationist Approach presents the requisite understanding of economic sustainability required within this research. The inclusion of economic, historical and socio-political fields of research proposes a wider understanding of the political economy and sustainability. The application of the Regulation Approach to the South African economy illustrates many problem areas that require attention. The examination found that firstly, aggregate demand in the South African economy was unsustainable due to the debt driven nature of demand under the asset price bubble of the mid to late 2000s. Secondly, aggregate supply also proved unsustainable as government is failing to provide any substantive growth within important sectors of the economy such as education and the provision of general services. Furthermore, the adoption of inflation targeting in South Africa poses a barrier to sustained economic growth as it focuses singularly on price inflation. The "reduced form" model of inflation targeting fails to account for market failures and a number of vital indicators of sustainability most notably, debt levels and asset prices. The inclusion of these indicators, and financial stability more generally, are found to provide a more holistic and sustainable approach to macroeconomic policymaking.

Following many other central banks around the world, the South African Reserve Bank has adopted inflation targeting as its monetary policy framework. The aim of this is to achieve low levels of inflation in order to attain price stability thereby promoting growth. In South Africa, the chosen band to target is 3%–6%. This has been criticised by many trade unions who are calling for the abandonment of inflation targeting. Despite targeting 3%–6%, it is not known whether this is the optimal inflation range for South Africa. Therefore, the aim of this study is to determine the inflation threshold level for South Africa using quarterly data for the period 1983 to 2010. The first section determines whether or not there is a long-run relationship between inflation and growth using the Johansen cointegration method. Exogeneity tests determine the causality between these variables. Vector error correction models are estimated if cointegration is found. The second part determines the threshold level of inflation using the method of conditional least squares. The inflation level that maximises the R-squared value and minimises the residual sum of squares gives an indication of the threshold level. The third part of the study determines whether or not inflation volatility has a significant impact on growth. The first part established that there is long-run comovement between inflation and growth.The causality is bidirectional with both variables being endogenous.Findings regarding the threshold level show that the current inflation targeting band of 3%–6% may be extended up to 9.5%. In addition, the range of inflation from 5.5% to 6.5% promotes economic growth in South Africa. Finally, the evidence suggests that inflation volatility does not have a significant impact on economic growth and the focus of policy should be directed towards the level of inflation as has been the case.

This thesis estimates the treatment effect of inflation targeting adoption on inflation, inflation variability, output, and output variability for 25 explicit inflation targeting countries. I implement the propensity score matching methodology that takes into account the problems of non-experimental nature, such as selection bias or selection on observable, and allows me to effectively mimic properties of randomized experiment and compute unbiased treatment effect estimates. I introduce a variety of propensity score matching methods that were recently developed in the treatment effect literature, including Nearest Neighbor, Radius matching, Kernel matching, and Inverse Probability Weighting. The results indicate that both industrial and developing inflation targeting countries exhibit lower inflation levels and at the same time higher output growth than non-targeting countries. The estimates are however in most cases statistically insignificant. Moreover, it appears that both industrial and developing countries achieve combination of lower inflation variability and output variability compared to non-targeting countries. Nonetheless, majority of the estimates are again statistically insignificant. The results are to a small extent sensitive to the choice of propensity score matching method. Radius matching with tight calipers (r=0.005, r=0.001) tends to provide the most reliable estimates. Balancing properties of the models are reasonable and compared to the previous research the standardised biases are quantitatively better.

In the third millennium CNB took over a Policy of Inflation Targeting. Czech Republic was one of the first countries which adopted that policy. This diploma is connected with bachelor thesis, entitled "Instruments of Monetary Policy in Czech Republic since 2000" written in 2009 and deals with explanations of tools and principles of monetary policy in terms of the political course of inflation targeting.

The thesis focuses on the analysis of the impact of the inflation uncertainty on the reinsurance pricing, particularly on its measures of risk. Vector autoregression models are used to predict the medium-term inflation and simulate different inflation paths. The consideration of various scenarios of future inflation captured by the stochastic modelling increases the value at risk (VaR) and the tail value of risk (TVaR) of mean ceded loss to the reinsurer. The thesis founds that the inflation uncertainty measured by the stochastic inflation matters and it is important from risk management and hedging perspectives. As a result, additional loadings could be added to the price for the mitigation of the inflation risk. Although the effect of stochasticity of the future inflation is not significant on mean loss, it is the case for the risk of measures, especially for the contracts with high retention relatively to the underlying exposure. JEL Classification F12, F21, F23, H25, H71, H87 Keywords reinsurance pricing, inflation forecasting, inflation risk, long-tail line of business Title Macroeconomic Uncertainty: An Exogenous Risk in Reinsurance Pricing

This thesis has been conducted through a qualitative research method in order to explain the concept of helicopter money and how to implement it in Sweden in line with present law. Milton Frideman was the first to coin the concept of helicopter money. His theory was that a permanent increase of the monetary base via money transferring to households would increase the aggregate demand and consequently result in an increase of the inflation level. Further Ben Bernanke has developed this theory to not only include transferring money to households but to the government in order to enable an increase in public spending and increase of inflation. Helicopter money is a form of direct monetary financing, which is illegal in Sweden today. There are ways to implement it though by doing an implicit transfer to the government through purchases of treasury bonds that are held in infinity. Helicopter money therefore requires cooperation between the government and the Riksbank. In order for helicopter money to be a sufficient tool the money that are being transferred needs to be consumed. Helicopter money has the unique quality that it’s irredeemable. Which result in an asymmetric treatment of the money, which mean that households never have to repay these money and therefore the consumption propensity rises. Helicopter money also weakens the currency, which results in an increase of inflation. Transferring money to the households would probably increase the inflation level but it also entails risks. If we on the other hand transfer the money to the government we can be absolutely certain that inflation will rise. The best way to implement helicopter money in order to achieve a higher inflation and at the same time taking present law into account is therefore to make an implicit transfer to the government. A good communication and explanation of the intentions are of great importance in order to retain the trust of the government and institutions. / Denna uppsats har genom en kvalitativ undersökning redogjort för begreppet helikopterpengar samt vilka förutsättningar som krävs för att implementera det i Sverige med hänsyn till rådande lagstiftning. Helikopterpengar bygger på en teori av Milton Friedman och innebär en permanent ökning av penningmängden via en transferering till hushållen vilket resulterar i en ökad aggregerad efterfråga och stigande inflation. Begreppet har utvecklats av bland annat Ben Bernanke som menar på att en transferering av helikopterpengarna likväl kan ske till staten för att öka offentliga utgifter och på det sättet driva upp inflationen. Helikopterpengar är en typ av direkt monetär finansiering som är förbjuden i Sverige med dagens lagstiftning. Det går dock att praktiskt tillämpa helikopterpengar genom att göra en indirekt transferering till staten genom köp av statsobligationer som hålls för evigt. Helikopterpengar kräver alltså ett samarbete mellan staten och Riksbanken. För att helikopterpengar ska få önskad effekt bygger det på att pengarna konsumeras. Helikopterpengar innebär en asymmetrisk behandling av pengarna vilket gör att hushållen inte behöver betala tillbaka pengarna i framtiden och konsumtionsbenägenheten ökar. Helikopterpengar urholkar kronans värde vilket leder till en svagare valuta som i sin tur också bidrar till en ökad inflation. En transferering till hushållen skulle med stor sannolikhet ge effekt på inflationsnivån men medför även risker. Genomförs däremot en transferering till staten kommer inflationen med säkerhet att öka då staten kan se till att varje krona spenderas. Bästa sättet att implementera helikopterpengar för att få störst effekt med hänsyn till rådande lagstiftning är alltså att göra en indirekt transferering till staten. Det är även viktigt att kommunicera intentionerna på ett pedagogiskt sätt för att marknaden ska behålla förtroendet för pengar och institutionerna.

Thesis(M.Com. (Economics)) -- University of Limpopo, 2019 / The reality is that the South African GDP is not within the range of what is projected the previous years. As the proposed expenditure for 2017/18 totals R1.56 trillion according to the 2017 budget speech, the treasury also need to reduce spending by a total of R26 billion over the next two years. Economic growth continues to be below expected levels in South Africa and unemployment is very high. The relationship between inflation, economic growth and government expenditure is important in both developing and developed countries. Like in any other economy in the world, the South African government’s most important role is to promote economic growth, and also to sustain high economic growth with low inflation (Brand South Africa, 2015). The study is completely based on secondary data. The methodology is quantitative which includes econometrical tools. For this purpose, this study applied Augmented Dickey-Fuller (ADF) and Phillips Perron unit root tests, Choice of the lag length, Johansen-Juselius Co-integration analysis, VEC Granger Causality/Block exogeneity Wald test, Vector Error Correlation Model, Diagnostic tests, Stability tests, Impulse response and Choleski/Variance decomposition methodology. From the findings, the results derived by applying Johansen-Juselius Co-integration indicate that there is a longterm relationship between the rate of inflation, economic growth and government expenditure, and also that both government expenditure and inflation impact negatively on economic growth. The results indicate that government expenditure encourages inflation impacting negatively on investment and the country’s GDP. Granger causality runs jointly from all three variables inflation, government expenditure and investment to the dependent variable (economic growth)

Kostnadsöverskridning är ett vanligt förekommande problem inom byggbranschen och kan ha en negativ påverkan på projektets omfattning. Detta problem baseras på flera faktorer. Syftet med denna studie har varit att undersöka de viktigaste orsakerna till kostnadsöverskridande i byggprojekt samt att hitta bästa möjliga åtgärder för dessa orsaker. För att uppnå syftet genomförde vi en större litteraturgenomgång och tog del av tidigare forskning av ämnet. Vi samlade in även data från enkätstudier av olika aktörer från olika företag. Denna data samlades in med hjälp av en enkät som företagen besvarade. Resultaten bevisar att kostnadsöverskridningar är ett problem i byggbranschen samt visar att det finns många olika orsaker som leder till att kostnader överstiger. De största orsakerna är fel kalkylering av projektet, och osäkerhet och oförutsedda händelser som händer i världen som hindrar att projektet slutförs enligt den budget som planerat. De åtgärderna som har kommit fram i resultaten är bland annat att åtgärden kan vidtas om organisationen är kompetent och har realistiska kalkyler samt gör väl genomtänkt projektstyrning i tid. / Cost overrun is a common problem in the construction industry and can have a negative impact on the scope of a project. This problem is based on several factors. The purpose of this study has been to investigate the main causes of cost overrun in construction projects and to identify the best possible measures for addressing these causes.   To achieve this purpose, we conducted an extensive literature review and examined previous research on the subject. We also collected data from survey studies involving various stakeholders from different companies. This data was gathered through a survey that the companies responded to.   The results confirm that cost overruns are a problem in the construction industry, and they demonstrate that there are many different causes that contribute to exceeding costs. The major causes include inaccurate project estimation and uncertainties and unforeseen events occurring in the world that prevent the project from being completed within the planned budget.   The measures that have emerged from the results include, among others, the need for competent organizations to take action and have realistic estimates. Additionally, well-thought-out project management should be implemented in a timely manner.

Det råder inga tvivel om att det finns en bostadsproblematik i Sverige, flertalet studier har bekräftat att människors avsaknad av bostäder är ett problem som bara växer sig starkare med tiden. Problematikens uppkomst och de breda arsenalet av aspekter som påverkar den är komplext. I den här studien är den huvudsaklig aspekten i fokus makroekonomin. Då författarna saknar tillförlitlig erfarenhet inom ämnet ifråga har tre böcker använts för kunskapsinsamling. Varpå “Macroeconomics: Principles, problems and policies” & “Principles of macroeconomics” har använts för den grundläggande förståelsen och “A Concise Guide to Macroeconomics: What Managers, Executives, and Students Need to Know” använts som ett uppslagsverk för en koncis och korrekt repetition av terminologin. Tre olika teorier kring makroekonomi är formulerade och kopplade till uppsatsens frågeställning. Teorierna diskuteras även utefter uppsatsens gång tillsammans med de svarrespondenterna angav under sina respektive intervjuer. Så även tillförlitligheten kring metodiken och de resultat som erhölls. Slutligen konstateras konsekvenser den rådande pandemin har på bostadsproduktionen tillsammans med betonandet av vikten i att bibehålla en stabil ekonomisk situation för att motivera högre risktagande och därmed bättre resultat i form av bostadsbyggande. / Whether there is a housing problem in Sweden it no longer a topic of debate, as it has been stated by several studies for generations that the lack of homes is only becoming an increasingly difficult problem. The nature of the issues stems from several different aspects of the nation where macroeconomics is the main aspect observed during this project. Since the writers lack reliable experience in the field, they turned to three books for enlightenment, where “Macroeconomics: Principles, problems and policies” & “Principles of macroeconomics” are read to get an understanding for the topic whilst “A Concise Guide to Macroeconomics: What Managers, Executives, and Students Need to Know” is used as an encyclopedia for a quick and concise recollection.Three different theories of microeconomic nature are described and connected to the problem at hand and discussed in later paragraphs. With a three-pronged approach to gathering data, the analysts produced a result that equates unemployment rates and interest rates to the production of houses. Further discussions are made regarding the legitimacy of the results and the methodology, whilst comparing the theories with the responses from conducted interviews. Conclusively, points are made about the consequences from the current pandemic, whilst also insisting that maintaining a stable economic situation is the most effortless manner to motivate higher risk taking and consequently better results in the form om housing construction.