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SummaryIn this paper some tools will be developed for analysing a simple inventory problem of the slow‐mover type with the special feature that the probability distribution of the demand interarrival times is unknown. The role of sufficient statistics in decision making is analysed for an arbitrary optimality criterion and particularly for the Bayesian criterion. A computational approach for the case of a Bayesian criterion is presented together with some numerical results.

SummaryThis report presents an approach to stochastic programming. It treats mainly the difficulties arising in formulating the problem and the possibilities to derive a deterministic problem by which it can be replaced. In a sense the approach of this report unifies different viewpoints on stochastic programming problems as they have been published in the literature.

SamenvattingIn dit artikel worden enige eigenschappen samenhangende met het aantal toppen van kansdichtheden afgeleid. Beschouwd wordt de situatie bij een dichtheid h(x, θ) (met θ parametervektor), die voor elke toegestaneparameterwaarde θɛθ tweemaal differentieerbaar is naar x, terwijl zowel h zelf, als zijn eerste en tweede afgeleide naar x, continu zijn in (x, θ). In paragraaf 2 worden enige eigenschappen afgeleid van de verzamelingen θk (k > o) van parameterwaarden waar strikt k‐toppigheid optreedt (definitie in paragraaf 1) en θo van die parameterwaarden, waarbijh(x, θ) voor geen enkele k (> o) aan de eisen voor strikte k‐toppigheid voldoet. In paragraaf 3 wordt h(x, θ) gespecialiseerd tot een lineair mengsel van twee kansdichtheden en in paragraaf 4 wordt gedetailleerd het geval van een lineair mengsel van twee normale dichtheden nagegaan.

Risk management can either protect or endanger higher education institutions (HEIs) in South Africa. A crucial determining factor is how the core risks for these institutions are identified and mitigated. This article contributes to the continuing discourse on both risk management and managerialism in higher education. The thesis for this article is that the presence of a caring human spirit within HEIs is a necessary condition for them to fulfil their reason for existence. The purpose of this article is thus to reflect on the risk of HEIs not being able to fulfil their fundamental reason for existence due to the smothering or absence of a caring human spirit in these institutions. A reading of official and scholarly texts has shown that HEIs' primary reason for existence is embedded risk, namely a concern with the new or the unknown and by implication a critical curiosity about an uncertain future. The presence of a caring human spirit is not only a necessary condition for fulfilling the reason for the existence of an HEI, but also a crucial risk category currently absent from the standard list of institutional risk categories. Risk assessment reveals that the absence or smothering of a caring human spirit in HEIs poses a high to very high risk for their survival.

(...) In order to determine the appropriateness of learning material for distance education, eight assessment criteria were proposed during July 2000 at the annual conference of the International Association of Schools and Institutes of Administration, and have been published recently in a scholarly journal. This article, by applying these criteria in a case study, assesses the appropriateness of tuition in Public Administration for first-year students at Unisa. (...) The study guide is shown to be engaged in an effort to shift control of the learning process over the learners. The research shows that learners appear to be ready for learning material which enhances their competencies to learn and to think independently. This is enhanced by indications that the study guide provides learners with the opportunity to think for themselves and to prepare themselves as knowledge workers. (...) (Politeia/DÜI)

Purpose: Severely congested and ill resourced prison systems in Africa face unprecedented challenges amplified by COVID-19. South Africa has recorded the highest COVID-19 positivity rate in Africa and on March 15th 2020 declared a national state of disaster. The first prison system case was notified on April 6th 2020. Design/methodology/approach: A legal-realist assessment of the South African prison system response to COVID-19 in the 12 months following initial case notification focused on the minimum State obligations to comply with human rights norms, and the extent to which human, health and occupational health rights of prisoners and staff were upheld during disaster measures. Findings: A legal-realist account was developed, which revealed the indeterminate nature of application of South African COVID-19 government directives, ill resourced COVID-19 mitigation measures, alarming occupational health and prison conditions and inadequate standards of health care in prisons when evaluated against the rule of law during State declaration of disaster. Originality: This legal-realist assessment is original by virtue of its unique evaluation of the South African prison system approach to tackling COVID-19. It acknowledged State efforts, policy making processes and outcomes, and how these operated within the prison system itself. By moving beyond the deleterious impacts of the COVID-19 pandemic on the already precarious South African prison system, we argue for rights assurance for those who live and work in its prisons, improved infrastructure and greater substantive equality of all deprived of their liberty in South Africa.

AbstractA review is presented of the development over the years of the theory and practical use of Markov decision processes. To this purpose three periods are considered: before 1966, from 1966 till 1972, and after 1973. In all 3 periods there has been some contribution from the Netherlands, but particularly in the last period the research in the Netherlands on the subject has become a major stream. In this review particular emphasis is given to the work which has been done in the Netherlands, but the main line of the paper is determined by the development of the applicability of the available theory.

AbstractIn the paper it is demonstrated, how a dynamic programming approach may be useful for the analysis of Markov games or stochastic games. Markov games with finitely many stages are dealt with extensively. The existence of optimal Markov strategies is proven for finite stage Markov games using a shortcut of a proof by Derman for the analogous result for Markov decision processes. For Markov games with a countably infinite number of stages some results are summarized. Here again the results and the methods of proof have much in common with results and proofs for Markov decision processes. Actually the theory of Markov games is a generalisation. The paper contains short introductions into the theories of matrix games and tree games.

1. Research Ethics and Integrity in Social Sciences in Africa -- 2. A Critical Discussion on the Relevance of Biosocial Science Research Ethics Codes and Principles for Social Science Researchers in Africa -- 3. Research Ethics Governance – An African Perspective -- 4. African Social Science Research Ethics and Integrity -- 5. Ethics Review Framework and Guidelines for Social Science Research -- 6. A risk framework for research in social sciences -- 7. Human Dignity Protection in Social Science Research in Africa: The State and Role of National Research Guidelines -- 8. Vulnerability -- 9. Informed Consent In Africa – Integrating Individual And Collective Autonomy -- 10. Engaged Research: An African Macro-Ethics Perspective -- 11. Equity, Equality and Justice in Biosocial Science Research in Africa -- 12. Social Responsibility and Health Related Research -- 13. An African Perspective of Benefits in Social Science Research -- 14. Protecting Future Generations Through Social Responsible Research Ethics Practices -- 15. Data Sharing: Protecting Privacy and Confidentiality Amidst the Big Data Debate - Implications for Social Science Research -- 16. Promoting Research Integrity and Avoiding Misconduct - Perspectives On and From Africa -- 17. Unethical Authorship Deals: Concepts, Challenges and Guidelines -- 18. Building Research Ethics Capacity in Africa