2009 Ninth IEEE International Conference on Advanced Learning Technologies
Towards the enhancement of the learning process with different types of case based activities Boubouka M., Verginis I., Grigoriadou M., Zafiri I. Department of Informatics and Telecommunications, University of Athens, Greece {mboub,iliasver,gregor}@di.uoa.gr,
[email protected] Abstract
from concrete examples by adapting their experience to new contexts. A large number of empirical studies confirm the effectiveness of both aforementioned types of Case activities. However, recently a new proposal for designing Case activities was introduced. Gentner et al. underlined the fact that novice learners, in contrast with experts, are not always able to recall an appropriate Case when facing a new problem, even if they have already studied a similar one in the past. For this reason, they propose Case activities in which learners receive pairs of Cases and are asked to study them in comparison. With a series of empirical studies they confirmed that this helps the learners concentrate to the structural similarities of the given problem solutions and increases their ability to recall and adapt the acquired experience to similar problems in the future [5]. A large number of Educational Systems based on Cases has been developed in the recent years aiming to enhance the educational process and maximize the learning outcomes (REFLECTIVE LEARNER [6], ARCHIE, SUSIE [7], KITE [8], eCase [9], Turfgrass Case Library [1]). The basic component of these systems is a Case Library where already solved problems concerning a particular topic are archived. However, these systems mainly support only one type of Case activities: Cases as examples. Having as an objective to cover the limitations of the aforementioned systems, we designed a web-based educational environment, referred to as CASTLE, aiming to support the creation and elaboration of Case activities of all types. The main issue we had to confront during the systems’ design process concerned the content and the structure of Cases.
The use of authentic problems in the form of Cases in a variety of teaching activities is a well established method aiming to foster the development of problem solving skills. Although a large number of case based educational systems are available, none of them supports all the different types of case based activities. In this paper we present an empirical study, conducted in order to establish the design of a web-based educational environment, referred to as CASTLE, aiming to support the creation and elaboration of Case activities of all types.
1. Introduction Everyday and professional life are full of challenging problematic situations requiring high problem solving skills in order to be confronted. Recognizing this fact, formal education of all levels in the recent years placed focus on supporting the learners to develop this kind of skills by working out activities based on authentic problems, namely the Cases [1]. The literature review revealed that Cases in education can be found in two different types of activities, listed below in chronological order of appearance: (i) as problem solving activities, where problematic situations are presented to the students which are asked to deal with them and produce solutions (ii) as examples, where students are asked to study problems already solved by experts and use them as examples in order to confront similar problems themselves [1]. The Cases as problem solving activities (referred also in literature as Case method) have been used more than one century in Low and Business education [2], and lately it has been expanded in other faculties such as Medicine and Science [3]. Cases as examples appeared after 1980 along with Case Base Reasoning (CBR). CBR was initially created as a computational model to build Intelligent Systems but then it was examined as a cognitive and educational model as well [4]. CBR assumes that people can learn 978-0-7695-3711-5/09 $25.00 © 2009 IEEE DOI 10.1109/ICALT.2009.63
2. Cases in Teaching of Programming As we intended to initiate the application of CASTLE in the domain of Informatics, we performed a literature review concerning the exploitation of Cases in various Informatics topics. This review revealed that 652
In order to conduct the empirical study we developed educational material consisting of three problems (i.e. PrA, PrB, PrC) which required the development of similar algorithms for their solutions and in particular algorithms concerning array manipulation. Each problem aimed to support the equal in number Phases of the empirical study: Phase A (pre-test) – lasted 30 minutes: All students were asked to work out PrA in order to specify their ability to develop an array manipulation program based on their prior knowledge. Phase B – lasted 60-80 minutes: All students studied a Case concerning PrB. However, in this Phase students were divided in two groups, according to the structure of the Case they studied: Group1 students had in their disposition the Case following the structure S1 and those of Group2 following the structure S2. Phase C (post-test)– lasted 30 minutes: All students were asked to work out PrC in order to specify whether their ability to develop an array manipulation program was affected by the Case they studied during Phase B and the way the Case was structured. From a total of 310 students, that enrolled to the course 102 students (n=102) volunteered to participate in the Case study activity; 51 out of 102 students participated in the study forming Group1 while the rest 51 formed Group2. The students were divided in the groups randomly. To determine whether the way a programming Case is structured reflects to its effectiveness in supporting learning of programming concepts, we compared the performance of Group 1 and Group 2 in the pre-test and the post-test. The evaluation of the programs developed during pre- and post-test was performed by the two course teachers using a 5-point scale (0-4). Disagreements between evaluators were resolved through discussion. No significant difference was found in the t-test performed comparing the two groups on pre-test performance (t100= 0,107, p=0,915) (mean pre-test scores Group1=2,537, Group2=2,562). We conducted repeated General Linear Model (GLM) measures analysis of variance on students’ performances in pre- and post-test, with Case (pre-test vs. post-test) as the within-subjects factor, and Case structure (Group1 vs. Group2) as the betweensubjects factor. The Case factor refers to the students’ knowledge acquired by working out the Case during Phase B of the empirical study. To statistically evaluate the pattern of change in performances, we computed a “Case x Case structure” GLM analysis. The corresponding multivariate tests revealed that the Case factor contributes to the improvement of the post–test performance of both groups’. The “Case x Case structure” interaction yielded no significant effects (mean post-test scores Group1=2,537, Group2=2,562).
a great deal of research is available concerning the application of Cases in teaching of Programming. Two teams studied separately the way Cases should be developed in order to effectively achieve learning outcomes in Programming, concluding in two different structures. According to structure S1, proposed by Linn & Clancy [10], a Case should contain: (i) a statement of the problem, (ii) a description of the problem solving process by an expert, (iii) a listing of the code, (iv) study questions, (v) test questions. According to structure S2, proposed by Spooner & Skolnick [11]: (i) motivation, (ii) background, (iii) algorithm development, (iv) new programming concepts, (v) listing of the code, (vi) discussion and further study questions. The analysis of the structures revealed that both of them propose similar content for the Programming Cases. Particularly, both agree that the problem should be described and accompanied of an expert solution, explanative comments to this solution and a series of questions. The difference between the two structures lies in the way the explanation of the solution is delivered. According to structure S1, the explanation has the form of a two column table where all the basic decisions concerning the development of the solution are listed and commented. On the other hand, structure S2 proposes the gradual introduction of the solution, after analyzing the algorithm that should be implemented and the new programming concepts that should be used. In order to comparatively investigate the efficiency of those structures and collect evidence in order to design Case author scaffolding for the domain of Programming to be included in CASTLE, we conducted an empirical study presented in the following section.
3. The empirical study The empirical study was carried out during the winter semester of the academic year 2007-2008 in the context of the course “Introduction to Informatics and Telecommunications” offered in the first year of undergraduate studies of the National and Kapodistrian University of Athens. We selected the topic of Algorithms and Programming in order to investigate how Cases and particularly the way they are structured can effectively support the learning process in the context of teaching Programming concepts. The main research question of the empirical study was: Does the way a programming Case is structured reflects to its effectiveness in supporting learning of programming concepts?
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The results of the repeated measures analysis are presented in Τable 1.
Environments, 1999. Lawrence Mahwah, NJ, pp. 215 – 242.
F(1) 11.68 1.48
Associates:
[5] D. Gentner, J. Loewenstein, L. Thompson. “Analogical encoding: facilitating knowledge transfer and integration.” In K. Forbus, D. Gentner, & T. Regier (Eds). Proceedings of the 26th meeting of the Cognitive Science Society, Chicago, August 4-7 2004, pp. 452-457.
Table 1: Multivariate tests for time factor and for the interaction Case x Case structure Factor Case Case x Case structure
Erlbaum
p 0.001 0.226
[6] J. Turns, W. Newstetter, J.K. Allen, and F. Mistree, “Learning Essays and the Reflective Learner: Supporting Reflection in Engineering Design Education.” In Proceedings of the ASEE Annual Conference, 1997. Session 2230.
As can be seen in Table 1, the factor Case contributes to the improvement of the post–test performance of both groups’. This states the positive influence of the Case study on students’ performance. The Case structure factor had no statistically significant effect in students’ improvement. It seems that the way the case was structured does not reflect to its effectiveness in supporting learning of programming concepts.
[7] N.H. Narayanan, & J.L. Kolodner, Case Libraries in Support of Design Education: The DesignMuse Experience. In Proceedings FIE'95 (Frontiers in Education), American Society for Engineering Education (ASEE), Atlanta, GA, November 1995, pp.2b2.1.2, IEEE Press. [8] F. K.Wang, J.L. Moore, J. Wedman, and C.R. Shyu, “Developing a case-based reasoning knowledge repository to support the technology integration community”, in Educational Technology Research and Development, Vol. 51, No. 3, 2003, pp. 45-62.
4. Conclusions and future plans Although in the last years several educational systems based on cases had been design, none of the existing systems aim to support all the different types of activities in which Cases can be used in education. To cover this limitation, we designed the web-based learning environment named CASTLE. Furthermore, we conducted an empirical study in order to collect information for supporting the creation of Cases in CASTLE. The results of the empirical study confirmed the effectiveness of the use of Cases in teaching Programming but not in favor with one of the structures found in literature. Thus, both structures will be included in CASTLE and the Case authors will be free to select how they will structure their Cases without restrictions.
[9] Pantelis M. Papadopoulos, Stavros N. Demetriadis, Ioannis G. Stamelos, Ioannis A. Tsoukalas, "Online CaseBased Learning: Design and Preliminary Evaluation of the eCASE Environment," ICALT, pp.751-755, Sixth IEEE International Conference on Advanced Learning Technologies (ICALT'06), 2006. [10] M. Linn, & M. Clancy, “The case for case studies of programming problems”, Communications of the ACM, 35(3), 1992, pp. 121-132. [11] D. Spooner, & M. Skolnick, “Science and Engineering Case Studies in Introductory Computing Course for NonMajors”, SIGCSE CA, USA, 1997, pp. 154-158.
5. References [1] D.H. Jonassen, J. Hernandez-Serrano, “Case based Reasoning and Instructional Design: Stories to Support Problem Solving.”, Educational Technology Research and Development, 2002, Vol. 50, No. 2, pp. 65–77 [2] M.T. Copeland, The Genesis of the Case Method in Business Instruction. In the Case Method at the Harvard Business School. Mac Nair MP/Hersum AC, New-York, Mc Graw-Hill, 1954. [3] C.F. Herreid, Start With A Story: The Case Study Method of Teaching College Science, NSTA press, 2006. [4] J.L. Kolodner, and M. Guzdial, “Theory and Practice of Case-Based Learning Aids”. In Jonassen, D.H. and Land, S.M. (Eds.), Theoretical Foundations of Learning
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