Cointegration and dynamic linkages of international stock markets: an emerging market perspective

This study investigates the long-run relationships and short-run dynamic linkages between the stock exchange of Egypt and its counterparts in Group of Seven (G7) countries, prior to and following the tragic events of September 2001, utilizing Johansen’s cointegration and variance decomposition analyses. The empirical results show, inter alia, that : (i) The Egyptian stock exchange appears to share no pairwise long-run cointegration relationships with its counterparts in the G7 countries across the pre- and post-attack periods, with the UK stock exchange being the only exception in the pre-attack period. (ii) The price variation in the Egyptian stock market over the pre- and post-attack periods is predominantly accounted for by its own innovations. (iii) Lastly, the September 2001 attack and its worldwide repercussions seem to exert no conspicuous impact on the behavior of the Egyptian stock exchange, implying that the latter tends to stand aloof from global events.Stock Market Integration; Egypt; Johansen’s cointegration Analysis; Vector Error Correction Model; Variance Decomposition Analysis

Comovements and Causality of Sector Price Indices: Evidence from the Egyptian Stock Exchange

Contributing to the meagre published literature on interrelationships amongst stock market sectors of an economy, the present study sets out to examine both the long-run and short-run aspects of the inter-sectoral linkages in the Egyptian stock market. The data correspond to daily closing prices for twelve sectoral indices of the Egyptian stock market, covering the period between January 3, 2007 and January 18, 2010. The multivariate cointegration analysis reports evidence in support of existence of only a single cointegrating vector within the sectoral indices. Moreover, the results of Granger’s causality analysis show that the short-run causal relationships between the sectoral indices are considerably limited and, where they exist, virtually unidirectional. In general, these results lead to the conclusion that there is still room to derive benefits from portfolio diversification in the short run. However, investors with long-term horizon may not benefit from diversifying investments into the different sectors of the Egyptian stock market.Stock Market sectors; Egypt; Domestic portfolio diversification; Johansen’s cointegration analysis; Granger's causality analysis

Cointegration and dynamic linkages of international stock markets: an emerging market perspective

This study investigates the long-run relationships and short-run dynamic linkages between the stock exchange of Egypt and its counterparts in Group of Seven (G7) countries, prior to and following the tragic events of September 2001, utilizing Johansen’s cointegration and variance decomposition analyses. The empirical results show, inter alia, that : (i) The Egyptian stock exchange appears to share no pairwise long-run cointegration relationships with its counterparts in the G7 countries across the pre- and post-attack periods, with the UK stock exchange being the only exception in the pre-attack period. (ii) The price variation in the Egyptian stock market over the pre- and post-attack periods is predominantly accounted for by its own innovations. (iii) Lastly, the September 2001 attack and its worldwide repercussions seem to exert no conspicuous impact on the behavior of the Egyptian stock exchange, implying that the latter tends to stand aloof from global events

Comovements and Causality of Sector Price Indices: Evidence from the Egyptian Stock Exchange

Contributing to the meagre published literature on interrelationships amongst stock market sectors of an economy, the present study sets out to examine both the long-run and short-run aspects of the inter-sectoral linkages in the Egyptian stock market. The data correspond to daily closing prices for twelve sectoral indices of the Egyptian stock market, covering the period between January 3, 2007 and January 18, 2010. The multivariate cointegration analysis reports evidence in support of existence of only a single cointegrating vector within the sectoral indices. Moreover, the results of Granger’s causality analysis show that the short-run causal relationships between the sectoral indices are considerably limited and, where they exist, virtually unidirectional. In general, these results lead to the conclusion that there is still room to derive benefits from portfolio diversification in the short run. However, investors with long-term horizon may not benefit from diversifying investments into the different sectors of the Egyptian stock market

Cointegration and dynamic linkages of international stock markets: an emerging market perspective

This study investigates the long-run relationships and short-run dynamic linkages between the stock exchange of Egypt and its counterparts in Group of Seven (G7) countries, prior to and following the tragic events of September 2001, utilizing Johansen’s cointegration and variance decomposition analyses. The empirical results show, inter alia, that : (i) The Egyptian stock exchange appears to share no pairwise long-run cointegration relationships with its counterparts in the G7 countries across the pre- and post-attack periods, with the UK stock exchange being the only exception in the pre-attack period. (ii) The price variation in the Egyptian stock market over the pre- and post-attack periods is predominantly accounted for by its own innovations. (iii) Lastly, the September 2001 attack and its worldwide repercussions seem to exert no conspicuous impact on the behavior of the Egyptian stock exchange, implying that the latter tends to stand aloof from global events

Comovements and Causality of Sector Price Indices: Evidence from the Egyptian Stock Exchange

Contributing to the meagre published literature on interrelationships amongst stock market sectors of an economy, the present study sets out to examine both the long-run and short-run aspects of the inter-sectoral linkages in the Egyptian stock market. The data correspond to daily closing prices for twelve sectoral indices of the Egyptian stock market, covering the period between January 3, 2007 and January 18, 2010. The multivariate cointegration analysis reports evidence in support of existence of only a single cointegrating vector within the sectoral indices. Moreover, the results of Granger’s causality analysis show that the short-run causal relationships between the sectoral indices are considerably limited and, where they exist, virtually unidirectional. In general, these results lead to the conclusion that there is still room to derive benefits from portfolio diversification in the short run. However, investors with long-term horizon may not benefit from diversifying investments into the different sectors of the Egyptian stock market

Population and fertility by age and sex for 195 countries and territories, 1950–2017: a systematic analysis for the Global Burden of Disease Study 2017

Background: Population estimates underpin demographic and epidemiological research and are used to track progress on numerous international indicators of health and development. To date, internationally available estimates of population and fertility, although useful, have not been produced with transparent and replicable methods and do not use standardised estimates of mortality. We present single-calendar year and single-year of age estimates of fertility and population by sex with standardised and replicable methods. Methods: We estimated population in 195 locations by single year of age and single calendar year from 1950 to 2017 with standardised and replicable methods. We based the estimates on the demographic balancing equation, with inputs of fertility, mortality, population, and migration data. Fertility data came from 7817 location-years of vital registration data, 429 surveys reporting complete birth histories, and 977 surveys and censuses reporting summary birth histories. We estimated age-specific fertility rates (ASFRs; the annual number of livebirths to women of a specified age group per 1000 women in that age group) by use of spatiotemporal Gaussian process regression and used the ASFRs to estimate total fertility rates (TFRs; the average number of children a woman would bear if she survived through the end of the reproductive age span [age 10–54 years] and experienced at each age a particular set of ASFRs observed in the year of interest). Because of sparse data, fertility at ages 10–14 years and 50–54 years was estimated from data on fertility in women aged 15–19 years and 45–49 years, through use of linear regression. Age-specific mortality data came from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2017 estimates. Data on population came from 1257 censuses and 761 population registry location-years and were adjusted for underenumeration and age misreporting with standard demographic methods. Migration was estimated with the GBD Bayesian demographic balancing model, after incorporating information about refugee migration into the model prior. Final population estimates used the cohort-component method of population projection, with inputs of fertility, mortality, and migration data. Population uncertainty was estimated by use of out-of-sample predictive validity testing. With these data, we estimated the trends in population by age and sex and in fertility by age between 1950 and 2017 in 195 countries and territories. Findings: From 1950 to 2017, TFRs decreased by 49\ub74% (95% uncertainty interval [UI] 46\ub74–52\ub70). The TFR decreased from 4\ub77 livebirths (4\ub75–4\ub79) to 2\ub74 livebirths (2\ub72–2\ub75), and the ASFR of mothers aged 10–19 years decreased from 37 livebirths (34–40) to 22 livebirths (19–24) per 1000 women. Despite reductions in the TFR, the global population has been increasing by an average of 83\ub78 million people per year since 1985. The global population increased by 197\ub72% (193\ub73–200\ub78) since 1950, from 2\ub76 billion (2\ub75–2\ub76) to 7\ub76 billion (7\ub74–7\ub79) people in 2017; much of this increase was in the proportion of the global population in south Asia and sub-Saharan Africa. The global annual rate of population growth increased between 1950 and 1964, when it peaked at 2\ub70%; this rate then remained nearly constant until 1970 and then decreased to 1\ub71% in 2017. Population growth rates in the southeast Asia, east Asia, and Oceania GBD super-region decreased from 2\ub75% in 1963 to 0\ub77% in 2017, whereas in sub-Saharan Africa, population growth rates were almost at the highest reported levels ever in 2017, when they were at 2\ub77%. The global average age increased from 26\ub76 years in 1950 to 32\ub71 years in 2017, and the proportion of the population that is of working age (age 15–64 years) increased from 59\ub79% to 65\ub73%. At the national level, the TFR decreased in all countries and territories between 1950 and 2017; in 2017, TFRs ranged from a low of 1\ub70 livebirths (95% UI 0\ub79–1\ub72) in Cyprus to a high of 7\ub71 livebirths (6\ub78–7\ub74) in Niger. The TFR under age 25 years (TFU25; number of livebirths expected by age 25 years for a hypothetical woman who survived the age group and was exposed to current ASFRs) in 2017 ranged from 0\ub708 livebirths (0\ub707–0\ub709) in South Korea to 2\ub74 livebirths (2\ub72–2\ub76) in Niger, and the TFR over age 30 years (TFO30; number of livebirths expected for a hypothetical woman ageing from 30 to 54 years who survived the age group and was exposed to current ASFRs) ranged from a low of 0\ub73 livebirths (0\ub73–0\ub74) in Puerto Rico to a high of 3\ub71 livebirths (3\ub70–3\ub72) in Niger. TFO30 was higher than TFU25 in 145 countries and territories in 2017. 33 countries had a negative population growth rate from 2010 to 2017, most of which were located in central, eastern, and western Europe, whereas population growth rates of more than 2\ub70% were seen in 33 of 46 countries in sub-Saharan Africa. In 2017, less than 65% of the national population was of working age in 12 of 34 high-income countries, and less than 50% of the national population was of working age in Mali, Chad, and Niger. Interpretation: Population trends create demographic dividends and headwinds (ie, economic benefits and detriments) that affect national economies and determine national planning needs. Although TFRs are decreasing, the global population continues to grow as mortality declines, with diverse patterns at the national level and across age groups. To our knowledge, this is the first study to provide transparent and replicable estimates of population and fertility, which can be used to inform decision making and to monitor progress. Funding: Bill & Melinda Gates Foundation

The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century