Making a prescription drug

Many compounds have been developed to treat specific illnesses and conditions. However, in the past it was harder to analyse the interaction between compounds and drugs. But now we are able to state nonlinear medical models of several variables and find the right combinations of the compounds and drugs (that are showing promise) to treat a specific condition. We solve these problems with multi‐stage Monte Carlo optimization. An example is presented here along with a discussion of the scientific method and a new forecasting technique.     

An investigation into whether student use of graphics calculators matches their teacher's expectations

This research examines students’ use of graphics calculators and investigates the extent to which the students’ use meets their teachers aim when using graphics calculators in the classroom. The teacher's use of her graphics calculator was analysed over a week using Key Record software. The teacher was questioned about her aims and expectations for the students when using a graphics calculator. As a result an interview schedule for students was constructed in order to determine whether the teacher's aims had been met. It was found that in general all of the teachers’ aims were met to some extent by most of the students.     

An investigation into the teaching of mathematics to undergraduate economics students

This article attempts to present a novel application of a method of measuring accuracy for academic success predictors that could be used as a standard. This procedure is known as the receiver operating characteristic (ROC) curve, which comes from statistical decision techniques. The statistical prediction techniques provide predictor models and their goodness-of-fit; in addition, ROC analysis allows to assess the accuracy of the ability to discriminate from success and failures cases of a classifier or predictive model, and so it could be considered complementary to others more commonly used. Thus, the ROC curve is used to compare and interpret the relative contribution of each university entrance factor in the correct classification as success or failure of the academic performance, as well as to establish cut-off scores for admissions and counselling purposes. It is revealed that the ROC analysis allows us to identify the better university entrance factor for each subject in predicting students’ academic success.     

Some issues surrounding the use of algebraic calculators in traditional examinations

Algebraic calculators, with symbolic manipulation capabilities, are tools in some classrooms for 14–19-year-olds and their use in learning and teaching mathematics is likely to increase over time. At the time of writing their use in traditional examinations is permitted in Austria, France and the USA. Several other countries have considered their possible use in examinations. In the UK several government initiated working groups considered the implications of their use in academic mathematics examinations for 18-year-old students. The reports of these working groups have not been published. An overview of the issues they addressed is presented here and implications for future examinations are considered.     

The role of symbols in mathematical communication: the case of the limit notation

Symbols play crucial roles in advanced mathematical thinking by providing flexibility and reducing cognitive load but they often have a dual nature since they can signify both processes and objects of mathematics. The limit notation reflects such duality and presents challenges for students. This study uses a discursive approach to explore how one instructor and his students think about the limit notation. The findings indicate that the instructor flexibly differentiated between the process and product aspects of limit when using the limit notation. Yet, the distinction remained implicit for the students, who mainly realised limit as a process when using the limit notation. The results of the study suggest that it is important for teachers to unpack the meanings inherent in symbols to enhance mathematical communication in the classrooms.     

An investigation into the relationship of heuristic performance with network-resource characteristics

Constrained resource project management heuristics are analyzed and their performance is assessed related to well defined project types. Such results have shown that using the overall performance measure of a given heuristic can, in some situations, be misleading.An efficient heuristic, which combines resource and criticality factors is also proposed. Computational experiments on a set of 6120 networks varying in size from 45–666 activities, 3 resources, and under different network parameters are reported. The proposed heuristic outperforms the best existing dispatching rules in certain project classes and also on problem sets appearing in the literature.     

An extension of the truth table method to cross products

This paper provides a graphical (technical) exhaustive search algorithm for elements which belong to expressions containing cross products of sets. Initial tests suggest that this technique, an extension of the truth table technique, is superior to the currently employed method of verbal (symbolic) inclusion check. The method allows routine treatment of complicated expressions which contain cross products, utilizing the basic table     

Educational triage and ability-grouping in primary mathematics: a case-study of the impacts on low-attaining pupils

This case-study, drawing on an unanticipated theme arising from a wider study of ability-grouping in primary mathematics, documents some of the consequences of educational triage in the final year of one primary school. The paper discusses how a process of educational triage, as a response to accountability pressures, is justified by teachers on the basis of shared theories about ability and potential. Attainment gains show that some practices associated with the triaging process work for the school, pushing selected pupils to achieve the Government target for the end of primary school. However, other practices appear to coincide with reduced mathematical gains for the lowest attaining pupils and a widening of the attainment gap. This case-study examines the mechanisms behind this, focusing on resource allocation, and assumptions about learners and their potential. The paper suggests a need to create dissonance, challenging shared assumptions, such as fixed-ability, which currently support triage processes.     

Difference and differential equations in the mathematics of finance

Many problems arising in the mathematics of finance involve identical money flows at regular time intervals and are typically solved by appropriate valuation at a focal date or by setting up an equation of value. It is shown here that such problems can be viewed as special cases of a certain class of first‐order difference equations. Problems relating to continuous money flows can be viewed analogously as special cases of a certain class of ordinary first‐order differential equations. Students should thus be encouraged to view the concepts and techniques of the mathematics of finance as not being inherently different from those prevalent in more traditional applied mathematics.     

面向21世纪师专数学专业培养目标的定位

分析了目前师专数学专业面临的现状,对该专业的培养目标进行了探索性的定位,并提出了课程改革的初步方案.     

An analysis of the amount and characteristics of writing prompts in Grade 3 mathematics student books

Curriculum guidelines and professional organizations’ recommendations lack details about how often and how much students should write in mathematics and what characteristics should define their writing. This study presents an analytic framework that addresses how often students are prompted in student mathematics books to write, how much they may be encouraged to write, and the characteristics of the writing prompts. Consequently, 2,095 writing prompts in student books across 10 comprehensive Grade 3 resources were analyzed. Findings indicate a marked variation in how often and how much students are positioned to write. Most prompts have students explain what they did to solve a problem and why about number concepts, with most pressing for procedures. The greatest percentage of prompts had students write about their own solutions and do not urge them to include specific writing features.     

高等数学教学中落实素质教育之浅见

本文主要讨论了数学素质教育的重要性及如何具体在高等数学教学中培养学生的数学素质     

An investigation of assessment and feedback practices in fully asynchronous online undergraduate mathematics courses

Research suggests it is difficult to learn mathematics in the fully asynchronous online (FAO) instructional modality, yet little is known about associated teaching and assessment practices. In this study, we investigate FAO mathematics assessment and feedback practices in particular consideration of both claims and findings that these practices have a powerful influence on learning.

A survey questionnaire was constructed and completed by 70 FAO undergraduate mathematics instructors, mostly from the USA, who were each asked to detail their assessment and feedback practices in a single FAO mathematics course. Alongside these questions, participants also answered the 16-item version of the Approaches to Teaching Inventory. In addition, a novel feedback framework was also created and used to examine how feedback practices may be related to participants' approaches to teaching.

Results show that assessment and feedback practices are varied and complex: in particular, we found there was not a simple emphasis on summative assessment instruments, nor a concomitant expectation these would always be invigilated. Though richer assessment feedback appears to be emphasized, evidence suggests this feedback may not be primarily directed at advancing student learning. Moreover, we found evidence of a reliance on computer--human interactions (e.g. via computer-assisted assessment systems) and further evidence of a decline in human interactions, suggesting a dynamic that is both consistent with current online learning theory and claims FAO mathematics courses are becoming commodified. Several avenues for further research are suggested.     

Symmetry and the golden ratio in the analysis of a regular pentagon

The regular pentagon had a symbolic meaning in the Pythagorean and Platonic philosophies and a subsequent important role in Western thought, appearing also in arts and architecture. A property of regular pentagons, which was probably discovered by the Pythagoreans, is that the ratio between the diagonal and the side of these pentagons is equal to the golden ratio. Here, we will study some relations existing between a regular pentagon and this ratio. First, we will focus on the group of fivefold rotational symmetry, to find the position in the complex plane of the vertices of this geometric figure. Then, we will propose an analytic method to solve the same problem based on the Cartesian coordinates, a method where we find the golden ratio without any specific geometric consideration. This study shows a comparison of the use of complex numbers, symmetries and analytic methods, applied to a subject which can be interesting for general education in mathematics. In fact, the proposed approach can convey and link several concepts, requiring only a general pre-college education, showing at the same time the richness that mathematics can offer in solving geometric problems.     

An “Instrumental Approach” to Study the Integration of a Computer Tool Into Mathematics Teaching: the Case of Spreadsheets

This article reports on research focused on the integration of a specific computer tool, the spreadsheet, into mathematics teaching. After presenting some important results obtained by research in this area, we revisit these in the light of an instrumental approach, which we perceive as essential to analyse the construction of mathematical meanings in spreadsheet environments and to understand better the questions of technological integration. Then, these theoretical elements are used in order to design an exploratory experiment with grade 7 pupils and analyse its results.     

Instrumenting Mathematical Activity: Reflections on Key Studies of the Educational Use of Computer Algebra Systems

This paper examines the process through which students learn to make functional use of computer algebra systems (CAS), and the interaction between that process and the wider mathematical development of students. The result of ‘instrumentalising‘ a device to become a mathematical tool and correspondingly ‘instrumenting’ mathematical activity through use of that tool is not only to extend students' mathematical technique but to shape their sense of the mathematical entities involved. These ideas have been developed within a French programme of research – as reported by Artigue in this issue of the journal – which has explored the integration of CAS – typically in the form of symbolic calculators – into the everyday practice of mathematics classrooms. The French research –influenced by socio-psychological theorisation of the development of conceptual systems- seeks to take account of the cultural and cognitive facets of these issues, noting how mathematical norms – or their absence – shape the mental schemes which students form as they appropriate CAS as tools. Instrumenting graphic and symbolic reasoning through using CAS influences the range and form of the tasks and techniques experienced by students, and so the resources available for more explicit codification and theorisation of such reasoning. This illuminates an influential North American study– conducted by Heid – which French researchers have seen as taking a contrasting view of the part played by technical activity in developing conceptual understanding. Reconsidered from this perspective, it appears that while teaching approaches which ‘resequence skills and concepts’ indeed defer – and diminish –attention to routinised skills, the tasks introduced in their place depend on another –albeit less strongly codified – system of techniques, supporting more extensive and active theorisation. The French research high lights important challenges which arise in instrumenting classroom mathematical activity and correspondingly instrumentalising CAS. In particular, it reveals fundamental constraints on human-machine interaction which may limit the capacity of the present generation of CAS to scaffold the mathematical thinking and learning of students. This revised version was published online in July 2006 with corrections to the Cover Date.     

An investigation of phase-distribution moment-matching algorithms for use in queueing models

Algorithms for matching moments to phase-type distributions are evaluated on the basis of their performance in their intended application, queueing models. The moment-matching algorithms under consideration match two moments to a hyperexponential distribution with balanced means and three moments to a mixture of two Erlang distributions of common order. These algorithms are used to approximate an interarrival-time distribution for a queueing model, and the accuracy of associated performance-measure approximations is then used to evaluate the moment-matching algorithms. Three performance measures are considered, and attention is focussed on the steady-state mean queue length (number in system) of theGI/M/1 queue. Performance-measure approximations are compared to three-moment bounds and performance-measure values arising from hypothetical approximated distributions.     

Quadruples in the four-number game with large termination times

The discrete dynamical system of absolute differences defined by the map Ψ(x ₁, x ₂, x ₃, x ₄) = (| x ₂ - x ₁ |, | x ₁ - x ₁|, |x ₁ - x ₁ |, |x ₁ - x ₄ |) has been studied by many authors and one of the interesting questions is how to locate quadruples which converge to the fixed point (0, 0, 0, 0) in large numbers of steps. An elementary method is offered for obtaining such quadruples. The method is also able to find quadruples that will not converge to (0, 0, 0, 0).     

Generating the patterns of variation with GeoGebra: the case of polynomial approximations

In this paper, we report a teaching experiment regarding the theory of polynomial approximations at the university mathematics teaching in Sweden. The experiment was designed by applying Variation theory and by using the free dynamic mathematics software GeoGebra. The aim of this study was to investigate if the technology-assisted teaching of Taylor polynomials compared with traditional way of work at the university level can support the teaching and learning of mathematical concepts and ideas. An engineering student group (n = 19) was taught Taylor polynomials with the assistance of GeoGebra while a control group (n = 18) was taught in a traditional way. The data were gathered by video recording of the lectures, by doing a post-test concerning Taylor polynomials in both groups and by giving one question regarding Taylor polynomials at the final exam for the course in Real Analysis in one variable. In the analysis of the lectures, we found Variation theory combined with GeoGebra to be a potentially powerful tool for revealing some critical aspects of Taylor Polynomials. Furthermore, the research results indicated that applying Variation theory, when planning the technology-assisted teaching, supported and enriched students’ learning opportunities in the study group compared with the control group.