Islamic and conventional portfolios optimization under investor sentiment states: Bayesian vs Markowitz portfolio analysis

This paper investigates the portfolio optimization under investor’s sentiment states of Hidden Markov model and over a different time horizon during the period 2004–2016. To compare the efficient portfolios of the Islamic and the conventional stock indexes, we have employed two approaches: the Bayesian and Markowitz mean-variance. Our findings reveal that the Bayesian efficient frontier of Islamic and conventional stock portfolios is affected by the investor’s sentiment state and the time horizon. Our findings also indicate that the investor’s sentiment regimes change the Islamic and the conventional optimal diversified portfolios.Moreover, the results show that the potential diversification benefits seem to be more important when using the Bayesian approach than when applying the Markowitz approach. This finding is valid for the bearish, depressed, bullish and calm states in Islamic stock markets. However, the diversification of potential portfolios is significant only for the bullish and the bubble states in the conventional financial markets.The findings of the study provided additional evidence for investors to exploit googling investor sentiment states to evaluate the portfolio performance and make an optimal portfolio allocation.     

Marx 200: The Abiding Relevance of the Labour Theory of Value

ABSTRACT

Marxist political economy is alive and well, and not just because of the habitual turn to Marx in response to any crisis of capitalism. Both through Capital and through the continuing evolution of Marxism, Marxist political economy offers valuable insights that can illuminate the modalities of social and economic reproduction and the relationships between (different aspects of) the economic and the non-economic. Marxism’s presence has been felt through its own internal debates and debates with other approaches to political economy, and even through its influence on those reacting against Marxism. The key to the continuing relevance and analytical strengths of Marxist political economy lies in its capacity to provide a framework of analysis for unifying disparate insights into and critiques of the contradictions of capitalism across the social sciences. The instrument for forging that unity is Marx’s theory of value, the potential of which is examined and illustrated with reference to the Sraffian critique and two key concepts in Marxian political economy: the value of labour power and financialisation. They are explored in the light of the processes of commodification, commodity form and commodity calculation.     

结构性去杠杆下的中国宏观经济*——2018年中期中国宏观经济分析与预测

2018年以来中国经济平稳运行，物价水平稳定，就业形势整体向好，经济增长质量稳步提升。不过，当前中国经济仍然面临一定的下行压力，尤其需要警惕消费增速过快下滑、宏观税负进一步加重、民间投资复苏乏力、部分企业效益状况显著恶化、去杠杆过程中金融体系不稳定性加剧等主要风险点。此外，杠杆率高企是现阶段中国经济面临的突出问题，而且中国的杠杆率在不同部门之间以及各部门内部均体现出明显的结构性特点。为此，中央在2018年专门提出了“结构性去杠杆”的新思路。在“结构性去杠杆”稳步推进的大背景下，宏观政策既要积极应对经济下行压力，谨防去杠杆带来的经济增速超预期下滑风险，又要激发经济内生增长动力，促使经济实现长期可持续发展和“高质量发展”。     

加强新时代高校宿舍舍长队伍建设,助力“00后”大学生成长成才

加强新时代高校宿舍舍长队伍建设,更有利于积极发挥高校宿舍育人阵地的作用,高校宿舍舍长在教育管理工作中的重要性不可忽视。论文提出从提高新时代宿舍舍长工作的站位、加强宿舍舍长的角色认同与培养、加强宿舍舍长管理机制的制度建设三个方面,加强高校宿舍舍长队伍的建设,助力新时代“00后”大学生的成长成才。     

Unconscious Processes of Organizing: Intergroup Conflict in Mental Health Care

A critical but overlooked issue in Weick’s seminal work, The Social Psychology of Organizing (1969/1979), concerns ‘the heat’ of organizing processes, namely, the underground emotional processes underpinning the organizing of conflictual work relationships. We present a qualitative case study of psychiatric agencies mandated by public policy to collaborate but instead engaged in persistent conflict despite its deleterious effects on their working relationship and on the wellbeing of the clients they intended to serve. To explain these conflictual features of organizing, we integrate Weick’s organizing theory with systems psychodynamics to deepen the understanding of emotions in organizing, specifically the motivational forces underpinning sensemaking and actions between interacting psychiatric agencies. This integration of theories reveals a critical feature of the relationship between the conscious and unconscious organizing processes: When a threat is involved, sensemaking and action are overtaken by social defences, resulting in dysfunctional organizing of the primary task. Drawing on these findings, we enrich Weick’s seminal work by developing a model that portrays organizing as the ritualized interaction of emotions, sensemaking and behavioural responses.     

Auditors' Responses to Workload Imbalance and the Impact on Audit Quality*

Using detailed data for fieldwork hours and audit hours by rank from audit engagements in Korea, we examine whether audits conducted under workload imbalance, proxied by busy‐season audits, impair audit quality, and how auditors adjust staff assignments for busy‐season audits. We generally find that busy‐season audits are associated with lower audit quality, and that audit firms reduce the involvement of senior auditors during busy‐season audits. In addition, the greater the involvement of senior auditors and junior auditors, the lesser the deterioration in audit quality. Finally, although there is no increase in interim audits in response to workload imbalance during busy seasons, increasing interim audits can mitigate the negative impact of busy‐season audits on audit quality. Our results are relevant to auditors and regulators, who have expressed concerns about the adverse effects of workload imbalance on audit quality.     

Legal evolution of the concept of ‘home base’ for the purpose of determining labour and social security law applicable to European aircrew members

This paper has a dual aim: (1) to outline the legal evolution of the ‘home base’ concept and (2) to map the role of this concept in determining the law applicable (both employment law and social security law) to employment contracts of European aircrew members. An in-depth analysis of the relevant portions of (1) Reg. (EEC) No 3922/91, (2) Reg. (EU) No 465/2012, (3) Reg. (EU) No 83/2014, (4) EASA's 2014 Certification Specifications, and (5) the European Court of Justice's preliminary ruling on joined cases C-168/16 and C-169/16 is conducted.What emerges is that (1) the ‘home base’ definition, due to its subjectivity, has traditionally been susceptible to multiple interpretations and (2) due to regulatory ambiguity, the use of ‘home base’ to identify the labour laws applicable to airline workers has for a long time been inconsistent, ranging from one extreme (being considered a key element for this purpose) to the other (being assigned a secondary role). It was only in the last few years that some improvements were made, with Reg. (EU) No 465/2012 first and the European Court of Justice's 2017 preliminary ruling then, clarifying that the ‘home base’ concept must be assigned a central role in the determination of the law (both social security law and employment law) applicable to employment contracts in the aviation industry.     

大型装备制造业企业关键设备备件预警策略

近些年,国内一些大型装备制造企业为提高国际竞争力,从国外引进不少先进设备,但当这些设备发生故障需要更换备件却不能得到满足时,给企业造成了不同程度的损失。文章应用设备失效模式与后果分析(MFMEA)方法制定关键设备备件预警策略,有效降低关键设备停机风险及其所造成的损失。     

El efecto fin de mes en los principales mercados accionarios latinoamericanos

In equity markets, it is common to find calendar anomalies, which have been the subject of several studies in recent decades, even some of them showing that over time these anomalies have disappeared. In this context, this paper analyzes one of these anomalies, the end-of-the-month effect, in both return and volatility in six Latin American stock markets, namely Brazil, Mexico, Chile, Colombia, Peru and Argentina during the period of 1993-2011. The importance of the evidence for the existence of this anomaly is to allow testing whether the effect has been disappearing over time. The findings of this research show the existence of positive abnormal returns and abnormal volatilities on days associated with the change of months for most of the countries under analysis. This research was performed according to three different periods defined in the literature to analyze the impact of the end-of-the-month effect. This research not only examines the key indexes of each market, but also the individual stocks of each, giving a much larger and demanding sample, which can lead to better conclusions about the existence of the phenomenon. Also, the transaction volume analysis is included to validate some hypotheses related with the high cash flow in the turn-of-month period.     

Advertising a second-price auction

This study examines a symmetric private-value second-price auction model in which the seller solicits bidders at a cost, sets a reserve price, and receives a payoff which is a convex combination of revenue and welfare. The bidder’s valuations are drawn from a distribution with a decreasing hazard rate and non-decreasing virtual valuations. We find that at equilibrium the seller adopts an advertising policy which minimizes the uncertainty over the number of participants, and sets a reserve price which only depends on the distribution of valuations and the weight on revenue in the objective function. A welfare-maximizing seller is shown to advertise more than a revenue-maximizing seller, and a ceteris paribus increase in the advertising level is proved to increase the expected winner’s rent.