In this paper is tested validity of the neoclassical migration model. For this purpose, were used Fixed effects model and VAR model. Data contain period of years 2001 to 2010 from 14 regions of the Czech republic and dataset contains 140 observations. Empirical results of Fixed effects model show that socioeconomic determinants had signifficant influence on regional rate of migration in the Czech republic. The direction and strength of influence of the most explanatory variables corresponded to the neoclassical theory. Estimations of VAR model indicate that regional migration did not decrease disparities within regions. These results questioned validity of neoclassical migration model.

The aim of this PhD thesis is to analyze the history and current situation of hedge funds and assess their potential to destabilize financial markets. The findings of the analysis are used to validate the assumptions underlying the major regulatory changes of hedge funds in the key global economic centres after the financial crisis in 2008 and 2009. Since their inception early last century hedge funds have gone through a period of great expansion in the sixties, followed by a decline due to large losses sustained in the early seventies. The nineties meant a real breakthrough for hedge funds as a result of which they became prominent players in the alternative investment space. As of today, there is over ten thousand hedge funds that globally manage close to 3 trillion US dollars. Compared to mutual funds and other financial institutions the volume of assets under management is still relatively small, the rate of growth over the past fifteen years has however been very significant. What is emphasized with respect to the impact of hedge funds on financial markets is the contribution to increasing the liquidity and efficiency and their role on the financial derivatives market where hedge funds are actively involved in the transfer of risk. They are at the same time subject of criticism for their purported destabilizing effect on financial markets and contribution to fluctuations in the prices of investment instruments. Although the share of hedge funds in triggering major financial crises has not been conclusively established, these investment entities were one of the targets of the wide-ranging regulatory changes following the financial crisis of 2008 and 2009. The dissertation first discusses the history and current situation of hedge funds and defines the term hedge fund. The following section describes the basic characteristics and principles of their functioning and reviews the regulation in the major domiciles. The final chapter is focused on the empirical analysis of the impact of hedge funds on financial markets. The inputs for this analysis include a global hedge fund index and representative market indices and data from the CFTC on positions in the 10 year US government treasury note futures. In the first step the descriptive statistics for the transformed time series are presented. The second part of the analysis focuses on lagged correlations between returns and volatility of the global hedge fund index and representative market indices. Granger causality tests are applied in the following section to determine the relationships between the returns and volatility of hedge fund and representative market indices. In the final step of the analysis Granger causality tests are used to analyze the link between the changes in positions in the 10-year US treasury note futures held by hedge funds and the change in settlement prices of these futures with the aim to assess whether hedge funds have the capacity to move the market. In conclusion, the results of this analysis are discussed in light of the recent regulatory changes and the potential for the future growth of hedge funds is assessed.

Thesis (M. A. Agricultural Science (Agricultural Economics) -- University of Limpopo, 2019 / The relationship between farm and retail prices provides insights into marketing efficiency, consumer and farmer welfare. In light of this, much focus has been given to price transmission studies. Thus, price transmission studies have become increasingly important in Sub Saharan Africa because of its nature of providing clear insights information into our markets. Despite its importance in markets, there are a few studies analysing the mechanism through which prices are determined and transmitted from farm gate to retail markets in dairy markets in South Africa. The aim of the study was to investigate and analyse the nature of price transmission mechanism of pasteurised liquid milk and cheese in South Africa. The specific objectives were to determine the correlation between the milk production and quantity of milk processed in South Africa. Furthermore, there was a need to determine the direction of causality between the farm gate, processor and retail prices of cheese and pasteurised liquid milk in South Africa. It was also necessary to determine whether the price transmission of pasteurised liquid milk and cheese was symmetric or asymmetric in South Africa. The study used secondary time series data that covered a sample size of 17 years (2000 -2016) of pasteurised liquid milk and cheese in South Africa. Pearson correlation coefficient, Granger causality test and Vector Error Correction Model were used for data analysis. Pearson correlation results revealed that milk produced is perfectly correlated with the quantity of milk processed and it was positive. The Granger causality tests revealed that there was a no causal relationship between farm gate and processor, retail and processor and also between farm gate and retail for cheese. However, signs of independent causal relationship from farm gate to retail prices were visible. It also suggested a bidirectional causal relationship between processor and farm gate prices and also between retail and processor prices of pasteurised liquid milk. On the other hand, a unidirectional causality was found from retail to farm gate prices. The VECM results for pasteurised liquid milk showed asymmetric price transmission implying that retailers and processors react quicker to price increases than to price decrease. ii It is recommended that more focus be placed on investment in emerging dairy farmers in order to increase production. This can be done through the input price subsidies, grants and education on modern technologies. The government should also implement the price monitoring cell in order to protect the consumers from unfair prices passed on by the retailers. / Services SETA and National Agricultural Marketing Council (NAMC)

The research examines how the banking sector in Zambia faired in the wake of the global financial crisis, and the ensuing global recession that followed. Even prior to the crisis, weaknesses within the Zambian Banking sector were already identified by a World Bank/IMF financial sector assessment. The research therefore aims to gain a better understanding of the potential destabilizing factors to the Zambia Banking sector, and provide key players (Policymakers, Regulators and Banks) with knowledge on how best to manage and overcome these adverse effects, in times of a financial crisis. A Vector Error Correction Model (VECM) is estimated using commonly identified macroeconomic and banking sector indicators from selected Anglophonic African countries that were affected by the crisis at the time. The selected variables include, Return on Assets (ROA); Non-Performing Loans (NPL); Foreign Assets (FA); Interbank Lending Rate (IBLR); Liquidity (LQD); Credit to Private Sector (PRV); Foreign Exchange Rate (FOREX); Inflation (INFL); Copper Price (CU); and a ‘dummy’ variable (CRISIS). The direction of causality between the variables is further established using the VAR Granger Causality Test. Results of the model suggests that although the CRISIS was found to cause the ROA, it had no significant effect on its outcome, implying that overall the crisis had very little effect on the Zambian banking sector’s profitability. It was the liquidity (LQD) variable instead which was found to have a significant effect on the ROA. In times of a financial crisis, it is therefore recommended that policy makers and regulators apply more stringent regulatory and monetary policy instruments. This would counter the adverse effects on the liquidity and profitability of the Banking sector, and thus ensure its stability.

Thesis (M. Com. (Economics)) -- University of Limpopo, 2019 / Financial markets and quite a diverse number of financial instruments have been growing in a controlled manner in recent decades in terms of value and volume. Brazil, Russia, India, China and South Africa (BRICS) are distinguished as having the fast growing markets in the universe compared to other markets of emerging economies, according to their promising economic prospective and demographic power. This study investigated the effects of government stock on investment activity in BRICS countries. This study used panel autoregressive distributed lag model (PARDL), Engel-Granger causality test, impulse response functions (IRF) and variance decomposition tests. Such techniques were applied to the annual data for the periods 2001 to 2016 in order to determine the effects of government stock on investment activity. The variables (government stock on bonds, government stock on mutual banks, government stock on corporations and government stock on liquid assets), including gross fixed capital formation which is a measure of investment activity, were subjected to panel unit root tests and that confirmed different orders of cointegration. The existence of a long run relationship between investment activity and other macroeconomic variables used in this study was determined by means of the panel cointegration tests, where one lag was used. The PARDL showed that in the long run investment activity was positively influenced by government stock on mutual banks and government stock on liquid assets, and negatively related to government stock on bonds and government stock on corporations. The Engel-Granger causality test revealed existence of unidirectional movement between investment activity and government stock on corporations as well as from government stock on bonds to liquid assets. The impulse response function test showed the impulse percentage of fluctuation that the variables did contribute to each other, from various periods both in the short and long run. While the variance decomposition of investment indicated that Investment was shocked by its own innovations throughout all the periods. A critical evaluation is needed to avoid investment shocks, instability of investment activity, instability of financial markets and the economy as a whole.

No description available.

Air pollution and meteorological conditions impact COVID-19 mortality rates. This research studied Quito, Ecuador, using Granger causality tests and regression models to investigate the relationship between pollutants, meteorological variables, human mobility, and excess deaths. Results suggested that Mobility as defined by Google Mobility Index, Facebook Isolation Index, in addition to Nitrogen Dioxide, and Sulphur Dioxide significantly impact excess deaths, while Carbon Monoxide and Relative Humidity have mixed results. Measures to reduce Carbon Monoxide emissions and increase humidity levels may mitigate the impact of air pollution on COVID-19 mortality rates. Further research is needed to investigate the impact of pollutants on COVID-19 transmission in other locations. Healthcare decision-makers must monitor and mitigate the impact of pollutants, promote healthy air quality policies, and encourage physical activity in safe environments. They must also consider meteorological conditions and implement measures such as increased ventilation and air conditioning to reduce exposure. Additionally, they must consider human mobility and reduce it to slow the spread of the diseases. Decisionmakers must monitor and track excess deaths during the pandemic to understand the impact of pollutants, meteorological conditions, and human mobility on human health. Public education is critical to raising awareness of air quality and its impact on health. Encouraging individuals to reduce their exposure to pollutants and meteorological conditions can play a critical role in mitigating the impact of air pollution on respiratory health during the pandemic.

Investing in the stock market offers opportunities for wealth accumulation through variousstrategies. This thesis explores the pairs trading strategy with dual-class stocks differingonly in voting rights, aiming to reduce portfolio risk and outperform the market bench-mark. Using data from the Swedish Large Cap index (2003-2023), the study benchmarksthe strategy’s performance against the OMXSPI index, assessing total return, CAGR andthe Sharpe ratio for three different strategies. Depending on the predefined thresholds ofthe trading strategy, the study concludes that pairs trading can surpass a buy-and-holdapproach, showing the effectiveness of a market neutral trading strategy.

Keyword analysis in scientific articles is a method used to identify and evaluate the importance and relevance of specific words or phrases (keywords) within scientific literature. The primary goal of keyword analysis is to uncover the core themes, research trends, and conceptual frameworks within a given field or across multiple disciplines. It helps researchers understand scientific discourse's focus and ideas' evolution over time. This thesis performs keyword analysis on a repository of scientific publications through a combination of methods. It starts with extracting the available keywords, and it deals with the missing keywords data through data augmentation. Then, it utilizes a variety of statistical methods to gain insight into the publications. The study employs an implementation of LDA topic modeling to accurately categorize keywords into thematic groups, a Vector autoregression to explore keyword relationships, and temporal dynamics of keywords. Next, the research further examines the interdisciplinary connectivity of keywords, clarifying the collective nature of modern science. In conclusion, the thesis presents a comprehensive framework for keyword analysis in scientific literature, through a blend of data augmentation, natural language processing, temporal dynamics, and interdisciplinary examination, the study provides a robust tool for understanding the development and structure of scientific literature. The findings of this research have important implications for scholars, it allows navigating the vast amount of scientific literature more effectively and to discern the most influential ideas and trends shaping target fields. The methodologies implemented here offer an opportunity for any studies to methodologically search, extract, and identify keywords to find relevant papers and interpret the complex landscape of scientific communication. / Nyckelordsanalys i vetenskapliga artiklar är en metod som används för att identifiera och utvärdera vikten och relevansen av specifika ord eller fraser (nyckelord) inom vetenskaplig litteratur. Det primära målet med nyckelordsanalys är att avslöja kärnteman, forskningstrender och konceptuella ramverk inom ett givet fält eller över flera lämnar. Det hjälper forskare att förstå den vetenskapliga diskursens fokus och idéernas utveckling över tid. Denna avhandling utför nyckelordsanalys på ett arkiv av vetenskapliga publikationer genom en kombination av metoder. Den börjar med att extrahera de tillgängliga nyckelorden och hanterar de saknade nyckelordsdata genom dataaugtation. Därefter använder den en mängd statistiska metoder för att få insikt i publikationerna. Studien använder en implementering av LDA-ämnesmodellering för att noggrant kategorisera nyckelord i tematiska grupper, en vektorautoregression för att utforska nyckelordsrelationer och tidsmässig dynamik av nyckelord. Nästa steg i forskningen är att ytterligare undersöka den tvärvetenskapliga kopplingen mellan nyckelord, vilket klargör den kollektiva naturen av modern vetenskap. Sammanfattningsvis presenterar avhandlingen ett omfattande ramverk för nyckelordsanalys i vetenskaplig litteratur. Genom en blandning av dataaugmentation, naturlig språkbehandling, tidsmässig dynamik och tvärvetenskaplig undersökning, erbjuder studien ett robust verktyg för att förstå utvecklingen och strukturen av vetenskaplig litteratur. Forskningens resultat har viktiga implikationer för forskare; det möjliggör effektivare navigering i den omfattande mängden vetenskaplig litteratur och att urskilja de mest inflytdrikelserika idéerna och trenderna som formar målfälten. De metoder som införas här erbjuder en möjlighet för vilken studie som helst att metodiskt söka, extrahera och identifiera nyckelord för att hitta relevanta artiklar och tolka det komplexa landskapet av vetenskaplig kommunikation.

Visual attention improves sensory processing, as well as perceptual readout and behavior. Over the last decades, many proposals have been put forth to explain how attention affects visual neural processing. These include the modulation of neural firing rates and synchrony, neural tuning properties, and rhythmic, subthreshold activity. Despite the wealth of knowledge provided by previous studies, the way attention shapes interactions between cortical layers within and between visual sensory areas is only just emerging. To investigate this, we studied neural signals from macaque V1 and V4 visual areas, while monkeys performed a covert, feature-based spatial attention task. The data were simultaneously recorded from laminar electrodes disposed normal to cortical surface in both areas (16 contacts, 150 μm inter-contact spacing). Stimuli presentation was based on the overlap of the receptive fields (RFs) of V1 and V4. Channel depths alignment was referenced to laminar layer IV, based on spatial current source density and temporal latency analyses. Our analyses mainly focused on the study of Local Field Potential (LFP) signals, for which we applied local (bipolar) re-referencing offline. We investigated the effects of attention on LFP spectral power and laminar interactions between LFP signals at different depths, both at the local level within V1 and V4, and at the inter-areal level across V1 and V4. Inspired by current progress from literature, we were interested in the characterization of frequency-specific laminar interactions, which we investigated both in terms of rhythmic synchronization by computing spectral coherence, and in terms of directed causal influence, by computing Granger causalities (GCs). The spectral power of LFPs in different frequency bands showed relatively small differences along cortical depths both in V1 and in V4. However, we found attentional effects on LFP spectral power consistent with previous literature. For V1 LFPs, attention to stimuli in RF location mainly resulted in a shift of the low-gamma (∼30-50 Hz) spectral power peak towards (∼3-4 Hz) higher frequencies and increases in power for frequency bands above low-gamma peak frequencies, as well as decreases in power below these frequencies. For V4 LFPs, attention towards stimuli in RF locations caused a decrease in power for frequencies < 20 Hz and a broad band increase for frequencies > 20 Hz. Attention affected spectral coherence within V1 and within V4 layers in similar way as the spectral power modulation described above. Spectral coherence between V1 and V4 channel pairs was increased by attention mainly in the beta band (∼ 15-30 Hz) and the low-gamma range (∼ 30-50 Hz). Attention affected GC interactions in a layer and frequency dependent manner in complex ways, not always compliant with predictions made by the canonical models of laminar feed-forward and feed-back interactions. Within V1, attention increased feed-forward efficacy across almost all low-frequency bands (∼ 2-50 Hz). Within V4, attention mostly increased GCs in the low and high gamma frequency in a 'downwards' direction within the column, i.e. from supragranular to granular and to infragranular layers. Increases were also evident in an ‘upwards’ direction from granular to supragranular layers. For inter-areal GCs, the dominant changes were an increase in the gamma frequency range from V1 granular and infragranular layers to V4 supragranular and granular layers, as well as an increase from V4 supragranular layers to all V1 layers.