Teaching Methodologies and Open Source Software: Empirical Application to Econometrics and Mathematics Alcina Nunes and Carlos Balsa

Abstract — Nowadays, the software open source represents an important teaching resource. However, it is not sufficiently explored as an higher education teaching methodology. In subjects with a very specific goal, applied contents and attended by a small number of students, the is still preferred to the open source software. Aware of this reality, this paper presents a reflection about the use of open source software in Applied Econometrics and Mathematics. The adoption of two different software programmes – Gretl and Octave – allows the discussion about a comprehensive set of pedagogical, economical and technical advantages and some observed practical limitations. In practice, the refereed advantages are stressed when the students’ results are analysed. Their academic results benefit from the adoption of software which is executed, distributed and improved freely.

Index Terms — Econometrics, Mathematics, Open-Source software , Teaching methodologies. ——————————  ——————————

1 INTRODUCTION commercial software with which the teachers seem to have created strong personal and he access to open source software is professional links. Tnowadays a rather unexplored source of In the Escola Superior de Tecnologia e de academic pedagogic tools. Software Gestão do Instituto Politécnico de Bragança tools which are crucial to the promotion of, (ESTiG-IPB ) the use of open source software both theoretic and practical, learning is not uncommon. Indeed, the commercial processes in higher education teaching software is being substituted by open source institutions. software concerning operative systems, Along with commercial labels it is possible internet navigation, e-mail management and to find a large diversity of high quality free word processing programmes. Still, when the software. An excellent example of this application of software tools, in the teaching software is the software gathered in the Free methodological processes, is analysed more Software Foundation (FSF), established in carefully it is possible to verify that the use of 1985 to promote the use, study, change and commercial software is preferred to the use of redistribution of software (Free Software free software. Such observation is true, Foundation , 1985). The mentioned institution essentially, when such methodological encourages the use of free software that processes reach specific scientific areas results from individual and group targeted to a particularly small number of contributions, especially those connected with students. an academic or scientific background. The The relative independence of higher requirements are that each user should follow education teachers concerning certain the GNU General Public Licence which commercial software, associated with the defines all the aspects related to the methodological processes adopted in the application of open source software (see classroom and the development of a strong http://www.fsf.org ). customer loyalty, seems to constitute an However, in spite of the advantages of the obstacle to the adoption of open source open source applications, as the freedom of software as a teaching methodological execution, distribution and improvement, it is instrument. The non adoption of such tools possible to find in our high education schools seems to result from: (i) embedded teaching some resistance to abandon the use of practices achieved by the use of specific software to answer specific scientific and/or ———————————————— pedagogical issues; (ii) resistance to learn  Alcina Nunes. Escola Superior de Tecnologia e Gestão and/or experiment a now software tool and; de Bragança, Apartado 1134, 5301-857 Bragança. E- (iii) to some suspicion about what is available mail: [email protected]. gratuitously in the web. In short, it is possible  Carlos Balsa. Escola Superior de Tecnologia e Gestão de Bragança, Apartado 1134, 5301-857 Bragança. E- to state that such resistance to the adoption of mail: [email protected]. open source software, as an instrument of

- 1 - NUNES AND BALSA, TEACHING METHODOLOGIES AND OPEN SOURCE SOFTWARE: EMPIRICAL APPLICATION TO ECONOMETRICS AND MATHEMATICS methodological processes enrichment, results adoption of open source software is a not only from technical difficulties but also valuable option to the traditional software from cultural scepticism. Only like this it is programmes adopted in the public higher possible to explain the persistence of such education institutions. resistance even when the free tools approach The present paper is divided as fallows. the commercial tools in the sense that both Next section presents the open source are user friendly. software adopted mentioning their general Econometrics and numerical methods are features. Section 3 presents the advantages among the examples of scientific areas which and disadvantages of their adoption as a specificity and empirical applicability demands methodological tool, in general and in each the adoption of software programmes as one of the particular subjects mentioned. After teaching and knowledge transmission tools. a section where the empirical results are Software like Eviews, , SPSS, Matlab, discussed the final considerations will be or Matemática have nowadays an presented. ample diffusion into academic contexts. However, although the majority of property companies perform special prices to teaching 2 GRETL AND OCTAVE PRESENTATION institutions, not always their acquisition is seen as a priority by institutions facing budget Open source software is the designation of a constrains. Especially if the number of target set of operative systems which enjoy four students is not vast enough to justify the characteristics universally accepted as investment. Therefore the advantages essential for each user. These four presented by the open source software characteristics are divided in four types of associated with to the strong budget freedoms (which are never compulsory for the constrains, experienced by the public teaching users). Freedom to: (i) execute the software institutions, lead to the substitution of the for any kind of application; (ii) study and adapt commercial software by the free software. its functioning to particular needs; (iii) In the subject Applied Econometrics redistribute an unlimited number of copies, lectured in the Management course the use of and; (iv) improve and to make public the the traditional econometrical software modifications introduced in the software (Eviews, Stata, SPSS) was replaced by allowing that everyone benefit from the GRETL introduced improvements. The above (http://gretl.sourceforge.net/gretl_portugues.ht mentioned freedoms characterize, generically, ml ). No other subject of the course adopted the GRETL and OCTAVE software. open source software as a teaching The GRETL software (Cottrell e Lucchetti, methodological tool. In the institution, at all, 2007) can be described as a computer only other subject adopted open source programme aiming to perform econometric software as an methodological tool. The analysis and that uses a programming subject of Numerical Methods lectured to language. It is possible to find GRETL Electrical Engineering and Mechanical versions available for Windows and Linux Engineering courses adopted the OCTAVE operative systems. (http://www.gnu.org/software/octave/ ) as an The OCTAVE software (Eaton, 2002) can alternative to the commercial software Matlab be understood as a high level language produced by MathWorks, Inc. aiming to perform numeric computation. Its (www.mathworks.com ). Since the open interface, in the form of command lines, source software language is quasi totally allows “to call” functions aiming to solve compatible with the commercial software numerous linear and no-linear problems. The language, the previous mentioned software language is very intuitive making it easily present themselves as an exceptional overcome by students. The software also alternative in a context of budget constrains. contains a large number of pre-programmed The comparative analysis of the mathematical functions and numeric methods implementation of different open source which allow rapidly achieve the desired programmes to different subjects in different results, even in the case of complex courses allows to infer about the effectiveness problems. Although there is an OCTAVE of their adoption and the pertinence of extend version available to function in Windows the the use of free software to other subjects software is mainly developed to function in which use software tools as teaching Linux being a part of the Debian Linux or methodological instruments. SuSe Linux. The pedagogical, economic, technical and institutional consequences confirm that the

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3 ADVANTAGES AND LIMITATIONS OF THE OPEN numerical methods problems should be SOURCE SOFTWARE solved “by hand” with the help of a calculator. This was a severe limitation to the number The use of econometrical and mathematical and dimension of problems proposed. It was software in the classroom, as a teaching necessary to chose only a small number of methodological tool, is of great importance to problems, which should be the most the transmission of contents and the representative, not allowing to stress acquisition of empirical competences. particular cases of numerical methods. The designation of the subject Applied Another limitation was the dimension of the Econometrics points out that the knowledge proposed problems. They could only include a goals depend of the empirical application of small number of variables which do not mathematical and statistical concepts in the allowed the representation of real study field of the economical measurement. In cases. Finally the disparity of calculator particular, it is intended that the students models, more or less sophisticated, among achieve skills in the management of statistical students originated some disparity in the data which allow them to test and validate available tools. theoretical hypothesis and take scientifically Each software application advantages and grounded management decisions. This limitations are presented in Tables 1, 2 and 3. desired acquisition of competences process The presented advantages are divided in needs, therefore, the adoption of computer three essential parts: pedagogical, programmes suitable to reach the above economical and technical advantages. mentioned goals. Many of the software GRETL and OCTAVE The use of econometric software was not a advantages are generic and transversal to novelty, still, the difficulties felt by the students any open source software so they are when using the commercial software adopted common between the two programmes (Table and the financial cuts for the acquisition of 1). academic licences led to the adoption of GRETL. The use of traditional commercial software in and its non TABLE 1 availability outside the classroom turn into a GENERIC ADVANTAGES OF THE OPEN SOURCE deficient programme comprehension, by the SOFTWARE students, and in a wrong perception about the degree of difficulty of the empirical Pedagogical applications. Other disadvantage of the commercial econometric programmes referred * Freedom of execution (they can be installed in any to the limitation of its use outside the context compute and any place). Students can download and use the software in their personal computers outside of the normal classroom. This disadvantage the classroom. represented a practical impossibility to continuously evaluate the student’s * Promotion of a responsible and legally accepted progresses. The student could not develop attitude towards the utilization of computer software. Avoiding the illegal copy of commercial software self-leaning work outside the classroom and students are stimulated to perform ethical actions could not present more extended papers and concerning the intellectual and industrial property reports. rights. In the more empirical subjects of the * The open source software allows to each teacher and engineering courses the adoption of computer student to study and improve it. The constant software allows to focus the attention in improvements allow to teachers and students to be up physical phenomena and not only in the to date relating to the scientific advances. programming of mathematical methods used in modelling. In other cases, when the Economical intention is to illustrate the potential of certain * Budget saving for both institutions and students. mathematical tools, the use of computer programmes allows a quick return of results. Technical In the study plans of the Electrical * Possibility to use in several platforms and the Engineering and Mechanical Engineering consequent availability to different operative systems courses appears the subject of Numerical (, Apple Macintosh, Linux ). Methods where it was decided to introduce the use of the computer to solve the * Larger software warranty, security and stability and a larger immunity to virus and worms. classroom proposed problems. The use of the computer with the software OCTAVE solved difficulties related with several different limitations. Previously the

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As it was referred, the advantages of the The limitations of each one of the software, GRETL and OCTAVE adoption are common presented in Table 3, result from the teacher’s between them. They only distinguish in the perception. The limitations of each one of the pedagogical aspects (Table 2). This difference software analysed are, therefore, subjective shows, however, another advantage of the and, again, result from the pedagogical open source software – its adaptability to the specificities and needs of the subject were it scientific and pedagogic specificities of each was applied. subject and to the teaching methodology. This last presented advantage is fundamental in higher education teaching systems. TABLE 3 LIMITATIONS OF THE ADOPTED SOFTWARE

TABLE 2 GRETL OCTAVE ADVANTAGES OF THE ADOPTED SOFTWARE The teacher must study with detail the features and applicability of the software if he/she not possesses GRETL OCTAVE elementary knowledge related to computer science.

Pedagogical * Short number of support books in a particular national language (In this case, Portuguese). * Possibility of * Possibility of resolution of continuous evaluation real exercise problems. implementation through * Idiom of the programme – Only English. the realization of * Possibility of resolution of empirical papers. by the ample exercises without a __ * User interface is not so user-friendly or students great amount of effort. visually appealing compared with commercial software. * Possibility to use * Possibility of resolution of econometric software in a bigger number of . exercises and, The Gretl and Octave adoption specific consequently, of a bigger * Availability of the number of particular cases. limitations are almost concerned with the software and the traditional limitations of the open source respective manual. * Substitution of a large software. Namely the user interface of the number of different open source software is not so user friendly or * User friendly. calculator models by a Knowledge of computer unique tool of computation. visually attractive as some commercial programming is not software. Although the previous limitation needed. This advantage * Availability of a great was, in practice, observed only for Octave. is particularly important number of elementary pre- The number of academic/scientific to Management students programmed mathematical not familiar with functions which allow a publications concerning the use of open computer science. quick achievement of source software is very scarce. The manual results. are essentially restricted to each open source * Good compatibility with software web page. For example, it is possible traditional Word and * Inclusion of numerical data processors as algorithms coming from to find the manual for Gretl using the link Word and Excel. scientific “libraries” as http://ricardo.ecn.wfu.edu/pub//gretl/manual/ . LAPACK (Anderson et al, Additionally, the few manuals provided are * Easy manipulation of 1999). restricted to English language and are not statistical data generated in different * Possibility to focus on the available in a particular national language. For types of econometric resolution methods and not instance, the only book, in Portuguese, about software. on programming. Numerical Methods that refers to Octave as Programming these supporting tool is mentioned in reference [5]. * Availability of data methods in C or Fortran is bases coming from well fastidiously and subject to However, theses limitations can be easily known econometric errors which result in a compensated by some additional pedagogical manuals. large lost of time. effort.

4 EMPIRICAL RESULTS The more specific advantages, presented In the pedagogical advantages of the open by each one of the mentioned open source source software was stressed the importance software, concern to the specific goals and of the software application as a way to allow aims of the subjects were the software is the student continuous knowledge evaluation. adopted. Therefore the differences among the A continuous evaluation carried out through advantages presented by GRETL and the execution of empirical applications. Such OCTAVE refer to pedagogical advantages.

- 4 - IASK PROCEEDINGS advantage can be confirmed, in practice, by evaluation was not a mandatory evaluation the analysis of the student’s results. In method for the Applied Econometrics subject. particular, the results of the students As could observed in the previous table, subjected to the introduction of the open the pedagogical advantage of Gretl’s and source software Gretl and Octave as Octave’s software use, which refers to the pedagogical tools. continuous evaluation of students, is notorious The comparative analysis of the statistical and represents an added-value in terms of data from each one of the above mentioned academic success. This perception is more subjects – Applied Econometrics and evident in the Applied Econometrics subject Numerical Methods – and the open source for the Management Course. The presence in software programmes, GRETL and OCTAVE, classes was not mandatory for this subject respectively, is presented in Table 4. students. Indeed, in average, only 43% of the students had attended the classes and 29% were not ordinary students. 79% of the total TABLE 4 number of students had chosen the STATISTICAL DATA – STUDENTS RESULTS continuous evaluation method, thought. The simplicity of the software installation and use were the main reasons for the choice of the alternative non mandatory evaluation method. This evaluation method was even Course chosen for a great number of non ordinary

Electrical students who could not be present during Mechanical Engineering Engineering Management classes. The results, measured in terms of academic results are obvious – 100% of the students were evaluated positively. The Subject observed result surpassed one’s expectations Methods Methods

Numerical in such a way that the application of the Econometric software as a pedagogical tool persists in the Software GRETL OCTAVE classes. Number of students 14 50 33 In the Numerical Methods subject is also possible to verify equally good approval rates. Presence in classes 6 29 19 It is important to notice the Electrical Engineering course with 81% of academic No Ordinary Students 4 8 3 success. In opposition to these course students the students of Mechanical Presence 43% 58% 58% Engineering had showed fewer skills related Number of Students to the use of computers. That is due to the Evaluated Students 14 31 24 less usual adoption of computer programmes in other subjects of the course. It was also Continuous Evaluated 11 31 24 observed a major resistance in the use of the Students Linux operative system and consequently a Approved Students 14 25 16 major resistance to the use of the Octave Approved Students software. It is believed that could be the 100% 81% 67% Evaluated Students reason for the inferior approval rate – 67%. Nevertheless, such positive results were Approved Students possible due to the adoption of a continuous Total Number 100% 50% 48% evaluation methodology. of Students The students satisfaction concerning the Approved Students use of open source software was not formally Continous Evaluated 127% 81% 67% evaluated – was not made a formal Students questionnaire about their perception regarding the adoption of open source software as a teaching methodological tool – still, it seemed Before presenting the results expressed in to the teachers involved that they were Table 4 is important to mention two significant pleased with the use of this kind of software. notes: (i) the presence in classes was In particular, in the Econometric Methods mandatory for the ordinary students in both subject, the easy execution of the Gretl Electrical Engineering and Mechanical programme in the students personal Engineering courses; (ii) the continuous computers, its simplicity, the fact that the

- 5 - NUNES AND BALSA, TEACHING METHODOLOGIES AND OPEN SOURCE SOFTWARE: EMPIRICAL APPLICATION TO ECONOMETRICS AND MATHEMATICS software presents a Portuguese version and its compatibility with Word text processor were the fundamental aspects for students (even the less willing to adopted the use of new ACKNOWLEDGMENT software) be satisfied during classes. It was The authors wish to thank the helpful not perceived any resistance to the adoption th of the software. comments of the participants on the 18 Luso- For the Numerical Methods subject, Spanish Conference in Management, Porto, although it was verified some reluctance in 2008. some student less familiarized with computers (the reason were explained in last section), it was observed a great motivation to use the Octave. The enthusiasm was due to its great potential concerning numerical computation and to its simplicity. REFERENCES

[1] E. Anderson, Z. Bai, C. Bischof, S. Blackford, J. Demmel, J. Dongarra, J. Du Croz, A. Greenbaum, S. 8 CONCLUSION Hammarling, A. McKenney and D. Sorensen, “LAPACK Users’ Guide - 3rd Edition”, Society for Industrial and The practical application of specific open Applied Mathematics, 1999. [2] A. Cottrell and . Lucchetti, “Gretl Users’ Guide”, source software in scientific areas such available on http://gretl.sourceforge.net/ , 2007. applied econometrics or mathematics have [3] J.W., Eaton, “GNU Octave Manual”, Network Theory shown to be an option with a high degree of Ltd , 2002. pedagogical potential. The cost/benefit [4] , “Articles of Incorporation” , The Commonwealth of Massachusetts , 1985. relation is insignificant. The advantages [5] A. Quarteroni and F. Saleri, “Cálculo Científico com presented by the open source software are Matlab e Octave”, Springer –Verlag, 2007. clearly superior to the possible specific limitations of its adoption in some scientific areas. In theory, all the learning process Nunes. Alcina has a PhD degree in Economics, implicated actors – students, teachers and concluded in 2008, and is currently an Assistant institutions – can withdraw benefits from the Professor in the Instituto Politécnico de Bragança , Portugal. Her research interests and publications concern replacement of proprietary software for open to public policy evaluation, econometrics and source software. In practice, such benefits are microeconomics. observed by high academic success rates. The above presented conclusions have Balsa. Carlos has a PhD in Computational Sciences, conducted to the maintenance of the Gretl concluded in 2006, and is currently an Assistant Professor in the Instituto Politécnico de Bragança , and Octave applications and to advise its Portugal. His research interests and publications concern adoption as a pedagogical tool in higher to Numerical Methods applications. education institutions.

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