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The purpose of this paper is to empirically examine whether corporate insiders extract information from activity of outsiders, specifically the short sellers.

Using portfolio approach and Fama-MacBeth regressions, this study examines the relation between short interest and subsequent insider trading activities.

The following results are reported. First, there is a strong inverse relation between short selling and subsequent insider trading, which is partially due to common private information and same target firm characteristics. Second, insiders extract information from shorts. This information extraction effect is more pronounced for firms whose insiders have stronger incentives to extract shorts information (insider purchases, higher short sale constraints, and better information environments). Third, during the September 2008 shorting ban, the information extraction affect disappeared among the large banned firms, whose shorting activities were distorted.

The findings contradict the of-cited accusations corporate executives hold against short sellers. Instead, corporate insiders appear to trade in the same direction as suggested by shorting activities.

Among the vocal critics of short sellers are corporate insiders, who allege that short sellers beat down their stock prices. Many corporations even engage in stock repurchases to show confidence that the stock will perform well going forward despite the short sellers’ actions. This paper’s analysis on their personal portfolios suggests the other way around.

By focusing on how corporate insider trading is related to shorts information, this paper sheds new light on whether corporate decisions convey the true information the corporate insiders possess.

Control laws that are based on the nonlinear inverse dynamics (NID) of the aircraft offer the potential for providing improved levels of performance over conventional flight control designs. The NID and its application in the flight control during windshear penetration are introduced here. With the employment of a real engineering windshear model and NID, a low‐altitude windshear penetration flight control law is designed. The simulative calculation results indicated that the NID control logic works effectively in the trajectory control of the aircraft during the penetration of windshear.

Public attitudes are considered influential in the successful reintegration of offenders into society after release, however research into attitudes towards offenders with intellectual disability (ID) has received little attention. The purpose of this study is firstly to see if people hold differing attitudes towards the reintegration of offenders with ID compared to those without ID and secondly, to investigate whether this difference in attitude is because of differing implicit theories of intelligence (TOI). The effects of familiarity with ID were also measured.

In total, 200 participants read crime vignettes depicting crimes committed by offenders with and without ID and completed Dweck’s “TOI” scale.

Participants were found to have greater entity views of intelligence towards ID yet displayed more positive attitudes towards their reintegration than offenders without ID. The influence of demographics was mixed. It would appear attitudes towards offenders with ID are not as negative as initially thought.

Implications of these findings are discussed in terms of desistance and community integration.

While some care must be taken when interpreting the results, this study demonstrates positive results regarding the reintegration of offenders with ID. Attitudes may be changing for the better towards those with disabilities, which is positive in terms of the government and National Health Service (NHS) objectives to reintegrate people with ID successfully back into the community. Although limited in number, it is noted that community forensic mental health teams have been effective in managing offender risk and providing good quality care (Dinani,et al.,2010; Benton and Roy, 2008). They can provide more person-centred and specialist treatments options and have links with other community services, probation and the police (Royal College of Psychiatrists, 2014).

Community care is thought to lead to more timely treatments with more accessible support teams and services that those with ID would struggle to access in prison (Bradley, 2009). It can also lead to greater well-being and support as individuals are in a less restrictive environment and are closer to their social networks, acting as a protective factor against further reoffending (Benton & Roy, 2008; Bradley, 2009). Furthermore, it has been indicated significant financial savings would be achieved for the criminal justice system by reducing inpatient care and increasing community services and sentences, in addition to reducing the demand on prison spaces (Bradley, 2009; Benton & Roy, 2008).

To date, very few studies have used TOI to examine attitudes towards offenders, with none examining attitudes towards offenders with ID.

The coronavirus disease 2019 (COVID-19)-induced declining economic prospects and accompanying economic shocks present socioeconomic vulnerabilities for developing economies at the tranches of poverty, unemployment and minimal social security. South Africa is one of the countries that have the most precarious societies in developing nations due to the triple challenges of unemployment, poverty and inequality. As such, this paper investigates the impact of the pandemic on South African livelihoods.

This paper uses secondary data obtained from the National Income Dynamics Study – Coronavirus Rapid Mobile Survey (NIDS-CRAM) Wave 1 dataset to analyse the impact of COVID-19 on South African livelihoods.

The findings reveal that COVID-19 amplified the country's poor and vulnerable population's socioeconomic conditions because of the stringent Level 5 lockdown regulations that barred low-income households from making a livelihood. It further revealed that low-income households, who are the least educated, Black African, female and marginalized, were disproportionally socioeconomically affected by losing the main household income.

The research is limited in that it used secondary quantitative data that relied on a telephonic survey during the COVID-19 lockdown period.

This study offers a policy suggestion that increasing social grants during the pandemic will not have any significant impact on the livelihoods of many South Africans unless distributional inequalities are reduced.

The government needs to develop welfarist policies to protect the most vulnerable in society to limit the socioeconomic impact of pandemics and take proactive policy measures to reduce unemployment and income inequalities in the country.

The paper contributes to understanding the precarious nature of low-income households.

The purpose of this research is to design a robust high-performance nonlinear multi-input multi-output heating, ventilation and air conditioning (HVAC) system controller for temperature and relative humidity regulation. Buildings are complex systems which are subjected to many unknown disturbances. Further complicating the control problem is the fact that, in practice, buildings and their systems have static nonlinearities such as power saturation that make stability difficult to guarantee. Therefore, in order to overcome these issues, a control system must be designed to be robust (performance insensitive) against uncertainties, static nonlinearities and effectively respond to unknown heat load and moisture disturbances.

A state of the art nonlinear inverse dynamics (NID) technique is combined with a genetic algorithm (GA) optimisation scheme in order to improve robustness against uncertainty in the system's modelling assumptions. The parameter uncertainty problem is addressed by optimising the control system parameters over a specified range of uncertainty. The NID control structure provides further robustness with effective disturbance handling and a stability criteria that holds in the presence of actuator saturation.

The proposed method delivers significantly more energy efficient performance whilst achieving improved thermal comfort when compared with a current industry standard HVAC controller design such as proportional-integral-derivative. The expected excellent response to disturbances is also demonstrated.

This method can easily be extended to account for other parameters with a specified uncertainty range.

This research presents a method of optimised NID controller design which can be easily implemented in real HVAC controllers of building energy management systems with a high degree of confidence to provide high levels of thermal comfort whilst significantly reducing energy usage.

A novel HVAC optimised NID control strategy using the robust inverse dynamics estimation feedback control topology with GA optimisation for improved robustness and tuning over a range of parameter uncertainty is described, designed and its performance benefits shown through simulation studies.

This paper examines the determinants of savings among low-income households, regarded as non-Ricardian households (NRHs), in South Africa. NRHs comprise low-income households largely depending on government welfare benefits for sustenance. This research investigates socio-economic factors determining savings pattern of low-income households in South Africa.

The research makes use of the National Income Dynamics Study (NIDS) data set wave one to five. The longitudinal survey models are analysed in determining the socio-economic characteristics of NRH in South Africa. The estimators include Pooled ordinary least square (OLS), fixed and random effects methods.

The household grant contributes positively to the level of savings, but the savings level is still considerably low: majority of the low-income households have zero or negative savings. The average size of a NRH is about twice the size of the Ricardian, despite the NRHs’ debt burden impoverishing them.

The self-perpetuated poverty problem makes every factor in the vicious cycle both cause and effect of another factor, warranting reverse causality and threatening the reliability of Pooled OLS estimates for the research.

The growing cost of government grant hinges on the increased level of inflation while largely depending on the number of households entering the low-income threshold.

The study recommends that the government creates a more enabling environment for NRHs to engage in productive activities. Also they create more low-skilled jobs and encourage reduction of birth rate among low-income households; this will reduce their expenditure and increase their level of savings and will assist in pulling them out of the vicious circle of poverty. Government can boost NRHs’ savings through increase in various grants.

The study makes significant contribution towards addressing the unfortunate situation of household savings among low-income brackets in South Africa. The research corroborates other studies on the effectiveness of the fiscal stimulus package to boost the welfare and savings condition of NRHs in South Africa. The result explicitly confirmed the redistribution policy of the grant to the low-income household. The grant has a significant positive effect on the savings pattern of the household. An increase in it beyond the poverty threshold could indeed break the vicious circle of poverty since the effect does not only stop at expenditure but also pass through to savings, which may ultimately boost investment. Further studies should continue the investigation of grant transmission channels to investment and income.

The peer review history for this article is available at: https://publons.com/publon/10.1108/IJSE-11-2019-0692

I survey applications of Markov switching models to the asset pricing and portfolio choice literatures. In particular, I discuss the potential that Markov switching models have to fit financial time series and at the same time provide powerful tools to test hypotheses formulated in the light of financial theories, and to generate positive economic value, as measured by risk-adjusted performances, in dynamic asset allocation applications. The chapter also reviews the role of Markov switching dynamics in modern asset pricing models in which the no-arbitrage principle is used to characterize the properties of the fundamental pricing measure in the presence of regimes.

In a country that is marred by an excessively high unemployment rate, there is a need for policymakers to prioritise entrepreneurship in South Africa. The study aims to explore the determinants of self-employment among the youth in South Africa and in the process answer the following question: Who are the self-employed youths in South Africa?

Different potential predictors of self-employment empirically used in the literature were used in this study. A probit regression model was used with the binary self-employment variable as the dependent variable and a host of independent variables. A nationally representative survey consisting of youths was used in the analysis.

The findings show that financial literacy increases the odds of being self-employed. Secondly, the odds of being self-employed increase with age as mature people are expected to have gathered enough networks and wisdom over the years. Thirdly, being male decreases the odds of being self-employed. When it comes to education, the only category that statistically increases the odds of being self-employed compared with no schooling is the tertiary level of education. The other educational levels are all statistically insignificant. From a policy perspective, the government should promote self-employment by investing in financial literacy as well as increasing access to tertiary education among disadvantaged groups.

The study is one of the first, to the best of the authors’ knowledge, to examine the characteristics of the self-employed using a nationally representative survey in South Africa.

The purpose of this study is to explore the role of e-government in reducing corruption and achieving transparency from the perspective of citizens and public servants of the National Statistics and Information Authority in Afghanistan.

This study applies a mixed-method research design to explore whether e-government can combat corruption and increase transparency in the public sector of a developing nation. The data collection involves a survey of (n = 280) citizens and interviews with six National Statistics and Information Authority public servants. Data analysis includes descriptive statistics, Spearman’s correlation for the survey and qualitative content analysis for the interviews.

The results of this study reveal that e-government distributes and decentralizes power among public servants, reduces corruption and promotes transparency and accountability by reporting corruption through social media, online complaint forms, emails and the 450 toll-free number. In addition, the major factors are identified that reduce corruption through e-government.

This study proposes a model for using e-government that has implications for designers, developers and policymakers to create user-friendly systems that reduce bureaucracy and physical interactions with public servants while minimizing paper-based systems.

Governments can reduce corruption among high-ranking public servants by implementing a decentralized system that prevents system manipulation. This involves measures like surveillance, ICT training, process automation, reduced bureaucracy, simplified procedures and real-time customer support.

Despite the potential of e-government to reduce monopoly power and intermediaries among low-ranking officials, high-ranking Afghan officials still engage in corrupt practices. Nonetheless, 75% of Afghans believe e-government promotes transparency and accountability and reduces corruption.

To the best of the authors’ knowledge, this is the first study in the Afghan public sector that explores the role of e-government to reduce corruption and achieve transparency.

The purpose of this paper is to propose an approach, which is easy to implement, for estimating the thickness of the air layer that may separate metallic parts in some aeronautical assemblies, by using the eddy current method.

Based on an experimental study of the coupling of a magnetic cup core coil sensor with a metallic layered structure (consisting of first metal layer/air layer/second metal layer), which is confirmed by finite element modelling simulations, an inversion technique relying on a polynomial forward model of the coupling is proposed to estimate the air layer thickness. The least squares and the nonnegative least squares algorithms are applied and analysed to obtain the estimation results.

The choice of an appropriate inversion technique to optimize the estimation results is dependent on the signal-to-noise ratio of measured data. The obtained estimation error is smaller than a few percent, for both simulated and experimental data. The proposed approach can be used to estimate both the air layer thickness and the second metal layer thickness simultaneously/separately.

This model-based approach is easy to implement and available to all types of eddy current sensors.