Weighted Statistical Testing based on Active Learning and Formal Verification Techniques for Software Reliability Assessment

This work developed an automatic approach for the assessment of software reliability which is both theoretical sound and practical. The developed approach extends and combines theoretical sound approaches in a novel manner to systematically reduce the overhead of reliability assessment

ECONOMETRIC ANALYSIS OF DETERMINANTS INFLUENCING RISK-ADJUSTED PERFORMANCE OF MUTUAL FUNDS

Objective: This study explores the relationship between Mutual Funds' (UCITS) performance and nine macroeconomic variables using a Vector Autoregressive (VAR) model. It aims to understand the dynamics between these variables and UCITS performance.   Theoretical Framework: The study is grounded in economic theories and concepts relevant to macroeconomics and financial markets. The VAR model serves as the theoretical framework, facilitating the analysis of the interdependencies among variables.   Method: The research methodology involved the application of a VAR model to 92 quarterly observations from January 2000 to December 2022. Non-stationarity tests indicated that all variables were non-stationary in levels but became stationary after first-order differencing. Data collection methods included obtaining information on macroeconomic variables and OPCVM performance.   Results and Discussion: The findings indicate a long-term causality between OPCVM performance, and the macroeconomic variables studied. Significant variables affecting OPCVM performance include money supply, GDP, inflation rate, discount rate, and bond interest rate. However, interest rate and exchange rate showed no significant impact. The presence of an inertia effect suggests the utilization of Box-Jenkins ARMA modeling.   Research Implications: This study provides insights into the influence of macroeconomic factors on OPCVM performance, offering implications for investors, financial analysts, and policymakers. Understanding these relationships can aid in making informed investment decisions and formulating effective economic policies.   Originality/Value: The research contributes to the literature by employing a VAR model to analyze the relationship between OPCVM performance and macroeconomic variables in the context of the Moroccan market. The findings offer practical implications for stakeholders and advance the understanding of financial market dynamics.En este artículo, examinamos la relación entre el rendimiento de los Fondos de Inversión Colectiva en Valores Mobiliarios (OPCVM) y un conjunto de nueve variables macroeconómicas utilizando un modelo Vector Autoregressive (VAR). Las variables utilizadas en nuestro modelo son: precio del petróleo Brent, oferta monetaria, inflación, precio del petróleo Brent, tasa de descuento, tipo de cambio, tasa de interés de bonos gubernamentales, tasa de mercado monetario, tasa de depósito. El índice de rendimiento del OPCVM es una variable dependiente, y las otras variables son independientes. En este estudio, utilizamos 92 observaciones para el período de muestreo de enero de 2000 a diciembre de 2022, que corresponde a datos trimestrales. Según las pruebas de no estacionariedad de Dickey-Fuller (ADF) y Philips-Perron (PP), todas las variables incluidas en nuestro estudio no son estacionarias en niveles. Se vuelven estacionarias después de la diferenciación de primer orden. Existe una causalidad a largo plazo entre el rendimiento de los UCITS y las otras variables del estudio. Según los resultados, las variables macroeconómicas más significativas en la explicación del rendimiento del OPCVM son la oferta monetaria, el PIB, la tasa de inflación, la tasa de descuento y la tasa de interés de los bonos. Los resultados revelan la ausencia de un efecto significativo de la tasa de interés y la tasa de cambio en la explicación del rendimiento del OPCVM. La presencia de un efecto de inercia en la explicación del rendimiento del OPCVM marroquí sugiere el uso de la modelización ARMA de Box-Jenkins.Neste artigo, examinamos a relação entre o desempenho de Fundos de Investimento Coletivo em Valores Mobiliários (OPCVM) e um conjunto de nove variáveis macroeconômicas usando um modelo Vetorial Autoregressivo (VAR). As variáveis usadas em nosso modelo são: preço do petróleo Brent, oferta de moeda, inflação, preço do petróleo Brent, taxa de desconto, taxa de câmbio, taxa de juros dos títulos do governo, taxa de mercado monetário, taxa de depósito. O índice de desempenho do OPCVM é uma variável dependente, e as outras variáveis são independentes. Neste estudo, usamos 92 observações para o período de amostragem de janeiro de 2000 a dezembro de 2022, o que corresponde a dados trimestrais. De acordo com os testes de não-estacionariedade de Dickey-Fuller (ADF) e Philips-Perron (PP), todas as variáveis incluídas em nosso estudo são não estacionárias em níveis. Elas se tornam estacionárias após diferenciação de primeira ordem. Existe uma causalidade de longo prazo entre o desempenho do OPCVM e as outras variáveis do estudo. Com base nos resultados, as variáveis macroeconômicas mais significativas na explicação do desempenho do OPCVM são oferta de moeda, PIB, taxa de inflação, taxa de desconto e taxa de juros dos títulos. Os resultados revelam a ausência de um efeito significativo da taxa de juros e da taxa de câmbio na explicação do desempenho do OPCVM. A presença de um efeito de inércia na explicação do desempenho do OPCVM marroquino sugere o uso da modelagem ARMA de Box-Jenkins

Ethical Stochastic Objectives Programming Approach for Portfolio Selection

The paper develops an ethical multiple stochastic objectives approach to address the ethical portfolio selection problem in the stochastic environment under the Shari’ah compliant framework. Two random objectives considered in this paper which are maximizing portfolio return and maximizing social welfare of portfolio. The risk of portfolio is measured by covariance matrix of total return. The ethical stochastic objectives program approach is based on goal programming approach, a chance constrained approach and Shari’ah compliant framework. The model is applied on 60 stocks including conventional and Islamic securities in GCC. The results show that, portfolios with higher proportion of ethical Islamic securities in the portfolio and with higher expected loss the higher is the portfolio performance in terms of Sharpe measure. Keywords: Shari’ah compliant, Ethical investment, Goal programming, Multiple objectives, Stochastic Multiple objectives programming, Chance constrained approach, Sharpe index as portfolio performance measure

A multi-objective particle swarm optimization algorithm for business sustainability analysis of small and medium sized enterprises

Sustainability is the major issue of small and medium sized enterprises (SMEs) all across the globe. Although SMEs contribute to GDP of any country their negative contribution to environment is also significant. Prior studies on SMEs’ sustainability mainly classified into three categories—the correlation between environmental and social practices with economic performance, sustainable supply chain performance measurement, and empirical research on sustainability practices. There is no study that objectively derives the sustainable structure of SMEs through optimal combination of sustainability practices (inputs) and performance (outputs). Therefore, the main objective of this paper is to generate optimal structure of sustainable SMEs by combining neural network and particle swarm algorithm while considering Multi-Objective framework. The study uses data from 54 SMEs of Normandy in France and 30 SMEs of Midlands in the UK. The data was gathered through questionnaire survey. As we do not have the explicit expression of our objective functions, we train a neural network on our databases in order to enable the generation of value of the different objectives for any profile. We design and run a multi-objective version of particle swarm optimization (MPSO) to generate efficient companies’ structures. The weighted sum method is then used for different weights. The comparison of observed data and the results of the PSO analysis facilitates to derive improvement measures for each individual SME

Weighted Statistical Testing based on Active Learning and Formal Verification Techniques for Software Reliability Assessment

This thesis developed an automatic approach for the assessment of software reliability which is both theoretical sound and practical. The developed approach extends and combines theoretical sound approaches in a novel manner to systematically reduce the overhead of reliability assessment

Sellar recurrent hemangiopericytoma without metastasis: a case report

Primitive hemangiopericytomas of the central nervous system are rare and represent less than 1% of intracranial tumors. Their nonspecific clinical and imaging can be misleading and bring to a mistaken diagnosis of meningioma. Radical surgery is the treatment of choice, but must be supplemented with postoperative radiotherapy. Hemangiopericytomas have a high potential for recurrence and metastasis. Sellar location is very rare and can simulate a pituitary adenoma.We report a case of a 24 year-old woman diagnosed with sellar recurrent HPC without metastasis.Pan African Medical Journal 2016; 2

Evaluation des chocs de la politique monétaire sur l’inflation : Cas du Maroc

Monetary policy transmission channels play a crucial role in transmitting central bank decisions to macroeconomic magnitudes. Thus, the transmission mechanisms of a monetary policy conducted by a central bank can be grouped into four mechanisms, namely the interest rate channel, the credit channel, the exchange rate channel and the asset price channel. In addition, of these four monetary policy transmission channels, which can be measured, there are other channels which cannot be measured, namely the expectations channel and the risk-taking channel, etc Assessing the effectiveness of monetary policy decisions taken by a central bank involves assessing the effectiveness of monetary policy transmission channels; since the latter constitute mechanisms through which the decisions of a central bank are transmitted towards its objectives (economic activity and/or inflation). The objective of this article is to assess the long-term transmission channels of monetary policy in Morocco from the fourth quarter of 2007 to the first quarter of 2020 (50 observations). Thus, to measure the effects of monetary policy transmission mechanisms on inflation, a structural VAR model was used. The results obtained show the importance of the exchange rate channel, the weakness of the interest rate channel and bank credit, while the asset price channel is dysfunctional.   Keywords : monetary policy, channels of transmission, structural VAR. JEL Classification :  C32, C51, E52, E58 Paper type : Empirical research.Les canaux de transmissions de la politique monétaire jouent un rôle crucial dans la transmission des décisions d’une banque centrale aux grandeurs macroéconomiques. Ainsi, les mécanismes de transmission d’une politique monétaire menée par une banque centrale peuvent être regroupés en quatre mécanismes à savoir le canal du taux d’intérêt, le canal du crédit, le canal du taux de change et le canal des prix des actifs. De plus, de ces quatre canaux de transmission de politique monétaire, qui peuvent être mesurés, on trouve d’autres canaux qui ne peuvent être mesurés à savoir le canal des anticipations et le canal de prise de risque, etc. L’évaluation de l’efficacité des décisions d’une politique monétaire prises par une banque centrale passe par l’évaluation de l’efficacité des canaux de transmission de politique monétaire ; puisque, ces derniers constituent des mécanismes à travers lesquels les décisions d’une banque centrale se transmettent vers ses objectifs ( activité économique et/ou inflation). L’objectif de cet article est d’évaluer à long terme les canaux de transmission de la politique monétaire au Maroc du quatrième trimestre 2007 au premier trimestre 2020 (50 observations). Ainsi, pour mesurer les effets des mécanismes de transmission de la politique monétaire sur l’inflation, on a utilisé un modèle VAR structurel. Les résultats obtenus montrent l’importance du canal du taux de change, la faiblesse du canal du taux d’intérêt et du crédit bancaire, alors que le canal des prix des actifs est en dysfonctionnement.   Mots clés : Politique monétaire, canaux de transmission, VAR structurel. Classification JEL: C32, C51, E52, E58 Type de l’article : Recherche appliquée. &nbsp

Analyse théorique de l’évolution des stratégies de politique monétaire adoptées par Bank Al-Maghrib

The choice of a monetary policy strategy differs from one country to another depending on the objectives of the central bank and the exchange rate regime adopted by that country. The Majority of Central Banks are abandoning intermediate target strategies in favor of final (s) target (s) strategies. Since they set price stability as its priority objective. Inspired by this context, the Moroccan monetary authorities seek through reforms to put in place prerequisites for adopting a monetary policy strategy allowing it to achieve the objective of price stability, considered as the main objective of Bank Al-Maghrib in its last two statuses. The objective of this article, on the one hand is to deal with the theories relating to monetary policy strategies and on the other hand, to analyze the monetary policy strategies adopted by the Central Bank of Morocco. By adopting a review of narrative literature, the results showed that before 2006 Morocco had adopted a strategy of monetary anchoring through control of a monetary aggregate whether in the strict sense or in the broad sense (M1 or M3) . However, from 2006 and following the failure of the monetary anchoring strategy, Bank Al-Maghrib adopted another so-called multi-criteria strategy, which coexists with the exchange rate anchoring strategy. Thus, this work also explains that the reform of the exchange rate regime initiated by the Moroccan monetary authorities in 2018 through the gradual switch to a flexible exchange rate regime would aim to switch to an inflation targeting strategy when the flexibility of the exchange rate regime would reach an advanced level.   Keywords : Monetary policy, Central bank, Exchange rate regimes JEL Classification :  E52, E58, E42. Paper type : Theoretical article.Le choix d’une stratégie de politique monétaire diffère d’un pays à l’autre en fonction des objectifs de la Banque centrale et du régime de change adopté par ce pays. La majorité des Banques centrales abandonnent les stratégies d’objectif intermédiaire au profit des stratégies d’objectif (s) final (s). Puisqu’elles fixent la stabilité des prix comme son objectif prioritaire. En s’inspirant de ce contexte, les autorités monétaires marocaines cherchent à travers des réformes à mettre en place des prérequis pour adopter une stratégie de politique monétaire lui permettant d’atteindre l’objectif de stabilité des prix, considéré comme l’objectif principal de Bank Al Maghrib dans ses deux derniers statuts. L’objectif de cet article, d’une part, est de traiter les théories relatives aux stratégies de politique monétaire et d’autre part, d’analyser les stratégies de politique monétaire adoptées par la Banque centrale du Maroc. En adoptant une revue de littérature narrative, les résultats obtenus montrent qu’avant 2006 le Maroc avait adopté une stratégie d’ancrage monétaire à travers une stratégie de contrôle d’un agrégat monétaire que ce soit au sens strict ou sens large (M1 ou M3). Toutefois, à partir de 2006 et suite à la défaillance de la stratégie d’ancrage monétaire, Bank Al-Maghrib a adopté une autre stratégie dite multicritères, qui coexiste avec la stratégie d’ancrage du taux de change. Ainsi, ce travail explique aussi que  la réforme du régime de change entamé par les autorités monétaires marocaines en 2018 à travers le basculement graduel vers un régime de change flexible viserait le passage vers une stratégie de ciblage d’inflation lorsque la flexibilité du régime de change atteindrait un niveau avancé.   Mots clés : Politique monétaire, Banque centrale, Régimes de change. Classification JEL: E52, E58, E42. Type de l’article : Article théorique