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Probability and Statistics Questions and Tests : a critical analysis
No full textIn probability and statistics courses, a popular method for the evaluation of the students is to assess them using multiple choice tests. The use of these tests allows to evaluate certain types of skills such as fast response, short-term memory, mental clarity and ability to compete. In our opinion, the verification through testing can certainly be useful for the analysis of certain aspects, and to speed up the process of assessment, but we should be aware of the limitations of such a standardized procedure and then exclude that the assessments of pupils, classes and schools can be reduced to processing of test results. To prove this thesis, this article argues in detail the main test limits, presents some recent models which have been proposed in the literature and suggests some alternative valuation methods. Quesiti e test di Probabilità e Statistica: un'analisi criticaNei corsi di Probabilità e Statistica, un metodo molto diffuso per la valutazione degli studenti consiste nel sottoporli a quiz a risposta multipla. L'uso di questi test permette di valutare alcuni tipi di abilità come la rapidità di risposta, la memoria a breve termine, la lucidità mentale e l'attitudine a gareggiare. A nostro parere, la verifica attraverso i test può essere sicuramente utile per l'analisi di alcuni aspetti e per velocizzare il percorso di valutazione ma si deve essere consapevoli dei limiti di una tale procedura standardizzata e quindi escludere che le valutazioni di alunni, classi e scuole possano essere ridotte a elaborazioni di risultati di test. A dimostrazione di questa tesi, questo articolo argomenta in dettaglio i limiti principali dei test, presenta alcuni recenti modelli proposti in letteratura e propone alcuni metodi di valutazione alternativi.Parole Chiave: item responce theory, valutazione, test, probabilità
The Impact of the Financial Crisis on Earnings Management: Empirical Evidence from the Top 5,000 Non-Listed Stock Italian Companies
Get PDFAccount manipulation has been the subject of accounting discussions not only in the U.S. but across the world, especially during times of financial crises. This paper investigates the impact of the recent financial crisis on account manipulation probability by adopting the Beneish Model (1999, 2013) of eight performance ratios. The analysis has been conducted using the Top 5,000 Non-Listed Stock Italian Companies (Società Per Azioni) ranked by revenues during the time period 2005-2012. We use the AIDA Bureau Van Dijk database. We test the existence of earnings management (EM) within the Top Non-Listed Stock Italian Companies through a comparison between the pre-crisis period (2005-2008) and the crisis period (2009-2012). Our findings show that the number of firms with a higher likelihood of earnings manipulation decreases by 4.53% from the pre-crisis to crisis period. As a consequence, we argue that EM increases when the crisis is weak while EM decreases during the crisis period
Influence of information on behavioral effects in decision processes
Get PDFRational models in decision processes are marked out by many anomalies, caused by behavioral issues. We point out the importance of information in causing inconsistent preferences in a decision process. In a single or multi agent decision process each mental model is influenced by the presence, the absence or false information about the problem or about other members of the decision making group. The difficulty in modeling these effects increases because behavioral biases influence also the modeler. Behavioral Operational Research (BOR) studies these influences to create efficient models to define choices in similar decision processes
Multivalued linear transformations of hyperspaces
Get PDFThe purpose of this paper is the study of multivalued linear transformations of hypervector spaces (or hyperspaces) in the sense of Tallini. In this regards first we introduce and study various multivalued linear transformations of hyperspaces and then constitute the categories of hyperspaces with respect the different linear transformations of hyperspaces as the morphisms in these categories. Also, we construct some algebraic hyperoperations on Hom K (V,W), the set of all multivalued linear transformations from a hyperspace V into hyperspaces W, and obtaine their basic properties. Finally, we construct the fundamental functor F from HV K , category of hyperspaces over field K into V K , the category of clasical vector space over K
Rough Set Theory Applied To Hyper BCK-Algebra
Get PDFThe aim of this paper is to introduce the notions of lower and upper approximation of a subset of a hyper BCK-algebra with respect to a hyper BCK-ideal. We give the notion of rough hyper subalgebra and rough hyper BCK-ideal, too, and we investigate their properties
Fuzzy bi-objective optimization model for multi-echelon distribution network
Get PDFIt is important for modern businesses to search the ways for continuous improvement in performance of their supply chains. The effective coordination and integrated decision making across the supply chain enhances the performance among its various partners in a multi stage network. The partners considered in this paper are product suppliers, processing points (PP), distribution centres (DC) and retail outlets (RO). The network addresses an uncertain environment threatenedby different sources in order to captivate the real world conditions. The uncertain demand of deteriorating products and its dependent costs develop uncertainties in the environment. On the other hand, suppliers and processing points have restricted capacities for the retail outlets’ order amount happened in each period. A bi-objective non-linear fuzzy mathematical model is developed in which the uncertainties are represented by the fuzzy set theory. The proposed model shows cost minimization and best supplier selection coordination under the conditions of capacity constraints, uncertain parameters and product’s deteriorating nature. The fish and fish products give good examples for the proposed model. To solve, the model is converted into crisp form and solved with the help of fuzzy goal programming
The Lie-Santilli admissible hyperalgebras of type An
Get PDFThe largest class of hyperstructures is the one which satisfy the weak properties. These are called H v -structures introduced in 1990 and they proved to have a lot of applications on several applied sciences. In this paper we present a construction of the hyperstructures used in the Lie-Santilli admissible theory on square matrices
Some applications of linear difference equations in finance with wolfram|alpha and maple
Get PDFThe principle objective of this paper is to show how linear difference equations can be applied to solve some issues of financial mathematics. We focus on the area of compound interest and annuities. In both cases we determine appropriate recursive rules, which constitute the first order linear difference equations with constant coefficients, and derive formulas required for calculating examples. Finally, we present possibilities of application of two selected computer algebra systems Wolfram|Alpha and Maple in this mathematical area
Recognizability in Stochastic Monoids
Get PDFStochastic monoids and stochastic congruences are introduced and the syntactic stochastic monoid M L associated to a subset L of a stochastic monoid M is constructed. It is shown that M L is minimal among all stochastic epimorphisms h : M → M ′ whose kernel saturates L. The subset L is said to be stochastically recognizable whenever M L is finite. The so obtained class is closed under boolean operations and inverse morphisms
The sum of the series of reciprocals of the cubic polynomials with triple non-positive integer root
Get PDFThis contribution, which is a follow-up to author’s paper [1] dealing with the sums of the series of reciprocals of some quadratic polynomials, deals with the series of reciprocals of the cubic polynomials with triple non-positive integer root. Three formulas for the sum of this kind of series expressed by means of harmonic numbers are derived and presented, together with one approximate formula, and verified by several examples evaluated using the basic programming language of the computer algebra system Maple 16. This contribution can be an inspiration for teachers who are teaching the topic Infinite series or as a subject matter for work with talented students