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The non-observed economy (NOE) is a pervasive phenomenon worldwide, especially in developing countries, but the size of the NOE and its contributions to the overall economy are usually unknown. This paper presents an estimation of the average size of the NOE for the 31 provincial regions in China between 1992 and 2013.

This study uses the Defense Meteorological Satellite Program/Operational Linescan System (DMSP/OLS) nighttime light data combined with 11 existing surveys on or measurements of NOE for 191 countries or regions throughout the world, to measure the size of the NOE.

The results show that the NOE share is unevenly distributed among China's provincial regions, with the smallest being 3.19% for Beijing and the largest being 69.71% for Ningxia. The national average is 43.11%, while the figures for the eastern region, middle region, northeastern region and western region are 39.3%, 47.6%, 44.7% and 43.6%, respectively. The NOE estimates are negatively correlated with the measured gross domestic product (GDP) and GDP per capita, which suggests that developed regions tend to have less NOE.

The nighttime lights are used to measure the NOE for China's provincial regions. Compared with traditional databases, one of the prominent features of nighttime lights is its objectivity, as there is little human interference; therefore, it can be used to achieve more accurate results.

In the last 50 years, the Mediterranean Basin has experienced a doubling of its population. This demographic growth has been the cause of extensive land use changes that have undermined the ecological stability of large portions of its fragile ecosystems. The population of the Mediterranean countries is expected to grow by another 20 percent in the next 25 years, further increasing the pressure on the natural resources. In this paper, we present a methodology combining photosynthetic activity and human settlements both derived from satellite data for monitoring the effects of human settlements on the environment. We found photosynthesis decreasing as one moves from rural to urban settings in the north and increasing in the south Mediterranean countries. Regional scale assessments using this approach may help policy makers in designing appropriate measures to combat further environmental degradation.

Safety, one of the basic human needs for existence, is a very important factor in achieving a successful urban space. A lack of its presence could make it challenging for residents of a place to live and function effectively. Therefore, this study aims to identify the urban design attributes that would potentially enhance the perceived sense of safety, mainly focusing on two case studies in El-Sherouk neighborhood in Cairo. The two selected case studies are considered car-oriented due to their reduced levels of safety.

This study was conducted through a set of data collection phases from field surveys and survey questionnaires that infer the influence of the surrounding urban environment on a specific target group. Statistical Package for the Social Sciences (SPSS) statistical analysis tool was used to analyze data collected from survey questionnaires.

Finally, by the end of this research, a set of urban design qualities vital for achieving the desired levels of safety were introduced. The findings of this study revealed key urban design qualities that can potentially contribute to enhancing the perceived sense of safety as they showed a strong positive correlation: (1) imageability, (2) transparency, (3) complexity and (4) human scale and enclosure. Moreover, multiple linear regression indicates that urban design qualities are strong predictors of perceived safety.

This study presents a holistic approach to studying the relationship between urban design and perceived safety by examining two case studies located in El-Sherouk City in Cairo, Egypt. While previous research has focused on one theory of safety design such as crime prevention, defensible space theory, eyes on the street or safer city centers, this article tries to fill in the gap in the literature by analyzing all aspects of urban design and its correlation to an enhanced perceived safety. In addition, most of the previous studies have tackled the safety aspects of old urban settlements. However, this study tackles a new urban settlement.

The purpose of the study is to evaluate whether nighttime luminosity sourced from the Defense Meteorological Satellite Program-Operational Linescan System satellite sensors is a suitable proxy for measuring poverty in Africa.

Our study performs wavelet coherence analysis to investigate the time-frequency synchronization between the nightlight data and “income-to-wealth” ratio for 39 African countries between 1992 and 2012.

All-in-all, the authors find that approximately a third of African countries produce positive synchronizations between nighttime data and “income-to-wealth” ratio and hence conclude that most African countries are not at liberty to use nighttime data to proxy conventional poverty statistics.

In differing from previous studies, the authors examine the suitability of nightlight intensity as a proxy of poverty for individual African countries using much more rigorous analysis.

The purpose of this paper is to estimate the impact of the COVID-19 pandemic on the patterns of convergence/divergence among the districts in India. Specifically, this paper investigates if the impact is heterogeneous among different cohorts of districts (based on income distribution). The differential impact may lead to heterogeneous long-run growth paths, resulting in unbalanced development across regions within the country. A study of convergence can ascertain the possible trajectory of such development across regions. Investigation of this phenomenon is the primary aim of this study.

This paper uses the panel regression method for estimation. This paper uses high-frequency nighttime light intensity data as a proxy for aggregate output.

The authors observe a significant reduction in the convergence rate as a result of the pandemic. Across the cluster of districts, the drop in ß-convergence rate, compared to the pre-pandemic period, varied from approximately 33% for the poorer districts to close to zero for the richest group of districts. These findings suggest that the pandemic may lead to a wider disparity among different regions within the country.

This paper contributes to the literature in the following ways. First, to the best of the authors’ knowledge, this is the first paper to investigate the impact of COVID-19 on the convergence rate. A detailed look into the possible disparity in convergence among various regions is critical because a larger drop in convergence, especially among the poorer regions, may call for policy attention to attain long-term equitable development. The authors perform this exercise by dividing the districts into four quantile groups based on the distribution of night-light intensity. Second, while previous studies on convergence using nighttime light data have used a cross-sectional approach, this study is possibly the first attempt to use the panel regression method on this data. The application of this method can be useful in tackling district-level omitted variables bias. Finally, the heterogeneity analysis using different quantiles of the distribution of night-light intensity may help in designing targeted policies to mitigate the disparity across districts due to the shock.

This chapter investigates how night-time light images acquired from the Defense Meteorological Satellite Program’s Operational Linescan System provide spatial and temporal insight into the economic impact of the disintegration of Yugoslavia. First, the chapter provides an overview of the economic development in Yugoslavia using conventional statistics, and second, it presents an analysis of the disintegration of the federation by comparing official statistics with night-time light data. Evaluating the impact of the disintegration of Yugoslavia as a federation and the conflicts arising in the wake of the break up is challenging since reliable data is missing. Therefore, satellite images, as one of the few sources of objective information, are potentially of great importance. We used yearly Operational Linescan System composites covering the period 1992–2013. The analysis is divided into small geographical units (districts) based on the republics in the former Yugoslavia.

The life insurance industry has been exposed to high levels of longevity risk born from the mismatch between realized mortality trends and anticipated forecast. Annuity providers are exposed to extended periods of annuity payments. There are no immediate instruments in the market to counter the risk directly. This paper aims to develop appropriate instruments for hedging longevity risk and providing an insight on how existing products can be tailor-made to effectively immunize portfolios consisting of life insurance using a cointegration vector error correction model with regime-switching (RS-VECM), which enables both short-term fluctuations, through the autoregressive structure [AR(1)] and long-run equilibria using a cointegration relationship. The authors also develop synthetic products that can be used to effectively hedge longevity risk faced by life insurance and annuity providers who actively hold portfolios of life insurance products. Models are derived using South African data. The authors also derive closed-form expressions for hedge ratios associated with synthetic products written on life insurance contracts as this will provide a natural way of immunizing the associated portfolios. The authors further show how to address the current liquidity challenges in the longevity market by devising longevity swaps and develop pricing and hedging algorithms for longevity-linked securities. The use of a cointergrating relationship improves the model fitting process, as all the VECMs and RS-VECMs yield greater criteria values than their vector autoregressive model (VAR) and regime-switching vector autoregressive model (RS-VAR) counterpart’s, even though there are accruing parameters involved.

The market model adopted from Ngai and Sherris (2011) is a cointegration RS-VECM for this enables both short-term fluctuations, through the AR(1) and long-run equilibria using a cointegration relationship (Johansen, 1988, 1995a, 1995b), with a heteroskedasticity through the use of regime-switching. The RS-VECM is seen to have the best fit for Australian data under various model selection criteria by Sherris and Zhang (2009). Harris (1997) (Sajjad et al., 2008) also fits a regime-switching VAR model using Australian (UK and US) data to four key macroeconomic variables (market stock indices), showing that regime-switching is a significant improvement over autoregressive conditional heteroscedasticity (ARCH) and generalised autoregressive conditional heteroscedasticity (GARCH) processes in the account for volatility, evidence similar to that of Sherris and Zhang (2009) in the case of Exponential Regressive Conditional Heteroscedasticity (ERCH). Ngai and Sherris (2011) and Sherris and Zhang (2009) also fit a VAR model to Australian data with simultaneous regime-switching across many economic and financial series.

The authors develop a longevity swap using nighttime data instead of usual income measures as it yields statistically accurate results. The authors also develop longevity derivatives and annuities including variable annuities with guaranteed lifetime withdrawal benefit (GLWB) and inflation-indexed annuities. Improved market and mortality models are developed and estimated using South African data to model the underlying risks. Macroeconomic variables dependence is modeled using a cointegrating VECM as used in Ngai and Sherris (2011), which enables both short-run dependence and long-run equilibrium. Longevity swaps provide protection against longevity risk and benefit the most from hedging longevity risk. Longevity bonds are also effective as a hedging instrument in life annuities. The cost of hedging, as reflected in the price of longevity risk, has a statistically significant effect on the effectiveness of hedging options.

This study relied on secondary data partly reported by independent institutions and the government, which may be biased because of smoothening, interpolation or extrapolation processes.

An examination of South Africa’s mortality based on industry experience in comparison to population mortality would demand confirmation of the analysis in this paper based on Belgian data as well as other less developed economies. This study shows that to provide inflation-indexed life annuities, there is a need for an active market for hedging inflation in South Africa. This would demand the South African Government through the help of Actuarial Society of South Africa (ASSA) to issue inflation-indexed securities which will help annuities and insurance providers immunize their portfolios from longevity risk.

In South Africa, there is an infant market for inflation hedging and no market for longevity swaps. The effect of not being able to hedge inflation is guaranteed, and longevity swaps in annuity products is revealed to be useful and significant, particularly using developing or emerging economies as a laboratory. This study has shown that government issuance or allowing issuance, of longevity swaps, can enable insurers to manage longevity risk. If the South African Government, through ASSA, is to develop a projected mortality reference index for South Africa, this would allow the development of mortality-linked securities and longevity swaps which ultimately maximize the social welfare of life assurance policy holders.

The paper proposes longevity swaps and static hedging because they are simple, less costly and practical with feasible applications to the South African market, an economy of over 50 million people. As the market for MLS develops further, dynamic hedging should become possible.

This study uses machine machine learning techniques to assess industrial development in Africa.

This study uses nightlight time data and machine learning techniques to assess industrial development in Africa.

This study provides evidence on how machine learning techniques and nightlight data can be used to assess economic development in places where subnational data are missing or not precise. Taken together, the research confirms four groups of important determinants of industrial growth: natural resources, agriculture growth, institutions and manufacturing imports. Our findings indicate that Africa should follow a more multisector approach for development, putting natural resources and agriculture productivity growth at the forefront.

Studies on the use of machine learning (with insights from nightlight satellite images) to assess industrial development in Africa are sparse.

The purpose of this paper is to investigate drivers’ differing psychological perceptions of cyclists’ conspicuity according to active visibility aid configurations on clothing.

The flashing light-emitting diodes (FLEDs) were positioned on the major joints (shoulders, elbows, wrists, hips, knees, and ankles) in eight configurations and pre- and post-surveys were conducted.

The results indicated that there were significant differences among the eight configurations in observers’ detection and recognition of cyclists, contributions of FLEDs, and visibility of cyclists (p<0.001). Among the eight different configurations on joints, FLEDs on the hips, knees, and ankles were the most detectable, recognizable, and visible.

Most of the previous studies have investigated passive visibility aids and there is a lack of research on FLED configurations on major joints for cyclists. Thus, this study is expected to be beneficial to designers when developing active visibility aid clothing for cyclists.

The purpose of this paper is to examine safety lighting at an existing US government facility.

Field measurements of exterior illumination were conducted at four building sites housing laboratories, offices and a cafeteria at night and the findings were compared to the industry recommendations, the Illuminating Engineering Society of North America (IES) safety lighting recommendations.

Laboratory, office and cafeteria building exteriors were classified as “high hazard” due to area wildlife, potentially dangerous equipment and chemicals, the threat of intruders, and uneven terrain. Some sites' existing light levels fell far below industry recommendations and others greatly exceeded recommendations. Most of the existing lighting was uneven, unsustainable, rendered colors poorly, produced glare and/or remained energized when no one was present.

This study is limited by the small number of sites and limited geographical area of the sites. Lighting field studies can improve user safety, save energy and reduce facilities' waste.

This study employs a relatively simple approach to examine safety lighting that facility managers could adapt for their own facilities to inform improvements.

The current lack of lighting field studies, safety lighting research and case studies regarding government facilities is addressed by contributions of this research.