Cognitive and Metacognitive Educational Systems: Papers from the AAAI Fall Symposium (FS-10-01) How to Support Meta-Cognitive Skills for Finding and Correcting Errors? Erica Melis Andreas Sander Dimitra Tsovaltzi German Research Center for Artificial Intelligence (DFKI) Universität des Saarlandes German Research Center for Artificial Intelligence (DFKI) Stuhlsatzenhausweg 3 (Building D3 2) D-66123 Saarbrücken Stuhlsatzenhausweg 3 (Building D3 2) D-66123 Saarbrücken andreas.sander@dfki.de D-66123 Saarbrücken melis@dfki.de Dimitra.Tsovaltzi@dfki.de be presented in a variety of ways, with different kinds of feedback, diverse tutorial strategies and diverse sequencing of learning material. Adapting such features to the needs of individual students could contribute to better learning. We conjecture that erroneous examples will give students the opportunity to find and reflect upon errors in a way that will lead to deeper learning, while at the same time not causing students to feel ashamed or demotivated, as is more likely when their own errors are exposed. During the last years we conducted a number of experiments, some of them strictly controlled lab and classroom studies, other more preliminary less controlled classroom experiments, and a Wizard-of-Oz experiment. Abstract Meta-cognitive skills to be developed in learning for the 21st century is the detection and correction of errors in solutions. These meta-cognitive skills can help to detect errors the learner has made her/himself as well as errors others have made. Our investigations in learning from errors have the ultimate goal to adapt the selection and presentation to the learner so that he/she can better learn from erroneous examples others have made. In our experiments we found that (1) erroneous examples with help provision can promote students skill of find errors, (2) the benefit from erroneous examples depends on the relation between the student’s level and the example’s difficulty, i.e. if the student is prepared for the problem, (3) for many students it is very difficult to correct errors. Finding Errors in Erroneous Examples Our experiments (Melis & Kriesell 2009; Tsovaltzi et al. 2009; 2010) tested whether erroneous examples in the domain of fractions can help students learn in the context of Technology-Enhanced Learning (TEL). This could spare students the embarrassment and demotivation of confronting their own errors. We conducted lab studies and classroom studies with students of different curriculum levels to measure the effects of learning through erroneous examples. We summarize the results of these studies that compare learning gains in three experimental conditions: a control condition, a condition in which students were presented with erroneous examples without help, and a condition in which students were provided with help for error detection and correction. Introduction Some of the meta-cognitive skills to be developed in learning for the 21st century are the detection and correction of errors in problem solutions. These meta-cognitive skills can help to detect errors the learner has made her/himself as well as errors others have made, e.g., errors hidden in solutions on the web or in other instructions. However, confronting students with erroneous solutions of mathematical problems and asking them to find the error is rather unusual in most schools (except Japanese schools) and many teachers are ambivalent about – or even hostile to – discussing errors in the classroom (Tsamir & Tirosh 2003). Our ultimate goal is to use adaptive technology to help students to learn by dealing with errors. That is, help students learn mathematics by presenting erroneous examples together with exercises in an adaptive fashion within the TEL system ACTIVE M ATH, a web-based learning environment for mathematics. We hope to improve students’ cognitive competencies in math learning, as well as their metacognitive competencies in error discovery, error correction and self-monitoring. Erroneous examples are worked solutions that include one or more errors that the student is asked to detect and/or correct. Technology opens new possibilities of instruction with erroneous examples. For example, erroneous examples can Empirical Results The erroneous examples’ benefit depends on the relation between the student’s level and the example’s difficulty, i.e. the student’s readiness statement. and needs, (similar to the results of investigations dealing with more vs. less interactivity in (vanLehn et al. 2007)). We hypothesize that the effect of erroneous examples depends on when and how they are introduced to the students and whether students are supported in finding and correcting the error. Design c 2010, Association for the Advancement of Artificial Copyright Intelligence (www.aaai.org). All rights reserved. Erroneous examples in ACTIVE M ATH include instances of typical errors students make, which address standard prob- 64 lems students face with rule-application, or errors which target common misconceptions and address more fundamental conceptual understanding infractions. Erroneous examples consist of two phases: error detection and error correction. Based on pilot studies, we designed feedback for helping students understand and correct the errors. There are four types of unsolicited feedback: minimal feedback (flag feedback), error-awareness and detection (EAD) feedback, self-explanation feedback (realized as MCQs) and errorcorrection scaffolds. We conducted lab studies with 6th, 7th and 8th-graders and school studies with 9th and 10th-graders. The participants came from both, urban and suburban, German schools. All studies used three experimental conditions. The condition No-Erroneous-Examples (NOEE) was the control and included standard fraction exercises with minimal feedback and the correct solution, but no erroneous examples in the intervention. The condition Erroneous-Examples-With-Help (EEWH) included standard exercises, and erroneous examples with provision of help (EAD, error detection/correction MCQs, and error-specific help). The condition ErroneousExamples-Without-Help (EEWOH) included standard exercises, and erroneous examples but without additional help. The design included a pre-questionnaire, a pretest, a familiarization, an intervention, a posttest and a postquestionnaire. The pre- and posttests were counterbalanced. when asked to correct the errors in erroneous examples. We wanted to find reasons for these difficulties. Experimental Set-Up The experiment took place at a secondary school in Heusweiler, Germany. 35 7th grade students (8 male and 27 female students) participated in this experiment and for each students the experiment took 45 minutes. Before the main experiment started, each subject received a short introduction about the user interface. During all experiments a total of 102 instances of erroneous examples were processed and for 65 instances, students detected the error at first request. We used a WOz environment developed in our group in which the student and the Wizard can communicate. The Wizard (the second author) selected one to four predefined erroneous examples. The selection criteria included: (1) not too difficult to find the error, (2) errors are close to errors or misconceptions the student made in the pretest. Always, the first question to the subject was whether the computations in the exercise are correct. The Wizard’s plan was to first, ask the student why the result cannot be correct, then the subject should show where the error actually is and tell what the error is and why it is an error. Then the student was supposed to correct the error and simultaneously write down what was in her/his mind. In cases where subjects had problems with this method during problem solving, a retrospective protocol after the problem solving process was used. Both the thinking aloud method and retrospective protocol did not yet provide much input. Results In the studies with different levels of students we had results that showed differences in how erroneous examples with error detection and -correction help influence mathematics learning. We found that, at least, more advanced students (9th- and 10th-grade) benefit from erroneous examples with help in terms of cognitive skills in general, as opposed to erroneous examples without help, or no use of erroneous examples at all. We also found that erroneous examples as a whole and error detection and -correction help can promote conceptual understanding for the same students. Erroneous examples can also influence the metacognitive skill of error detection for less advanced (6th-grade) but highly competent students. We did not find evidence for the use of erroneous examples for medium-advanced students (7th- and 8th-grade). However, this can be a result of the combined high level and high competence which our participants had in comparison to the students of the 9th and 10th-grade. In those experiments we found that most students do not have the meta-cognitive skill of correcting errors. Why is this the case? Therefore, we wanted to employ the Wizard-of-Oz (WOz) technique (cf. http://en.wikipedia.org/wiki/Wizard of Oz experiment) in order to find out more about reasons of correction weaknesses. Results At first, many students claimed to see a correct solution and did not find the error at first try. This was the case for 47 out of the 102 instances. In 27 out of 65 cases the participants could not correct the error properly at all. That is, in more than 40% of the cases, in which the students spotted the errors, they could not correct them . In the following, we present two typical interaction excerpts which were based on the erroneous example containing a wrong computation. The translation of the task in English is The rain barrel: Ulli collects rain water in a rain barrel in his garden and waters the plants in his garden. After several days of rain the 320 liter barrel was filled. The day after the rains Ulli asks: yesterday I had 320 liter in the barrel. Then I used 5 12 liter for my plants. How much is still in the barrel? and he computes... 1 2 11 = 320 − 2 320 − 11 = 2 309 = 2 ... did he compute correctly? Please answer this question with ”YES” or ”NO” 320 − 5 Correcting Errors in Erroneous Examples In a WOz experiment we addressed the question, why many students – even those who can find the errors or can solve a (fraction) problem on their own – have great difficulties 65 In this interaction the participant first answered, that all computations in the exercise are correct, but then (after a short hint) the student found the error. Nevertheless, the student could not correct the mistake (compute the common denominator and adapt the two fractions), because the student did not know how the procedure works practically. This is a good example for the dissociation between execution (action) and monitoring (evaluation) or, the distinction between knowing that and knowing how (Ohlsson 1996), which we encountered in our earlier studies (Tsovaltzi et al. 2010). The student knew that the fractions have to have the same denominator before subtraction of two fractions is possible. However, the student did not know how to calculate a common denominator for the fractions. This makes a big difference. If a student knows what, he/she often only remembers the (name of the) algorithm that needs to be applied. This does not mean he/she knows exactly what to do/the single steps. That is, the student may not even remember the definition (rather than a vague notion) of a common denominator. Log-Excerpt 1 Original Log-Excerpt of a participant (behind the German you find the English translation) student:Ja En: yes WOz:Nein, es wurde nicht richtig net/argumentiert. En: no, the tion/argumentation is incorrect gerechcalcula- WOz:Warum kann das errechnete Ergebnis nicht stimmen? En: why can the result not be correct? student:Emm weil er die (320-11)/2 nicht soo rechnen darf. En: emm, because you cannot compute like this WOz:Genau, warum darf er das nicht? En: correct, why must he not? student:Weil er nicht die 320 auf die 11/2 mit drauf setzten darf. En: because he must not put the 320 on top of 11/2 Log-Excerpt 2 WOz:Was muss er machen, damit er das auf einen Bruchstrich schreiben darf? En: what should he do before writing this in the nominator? Original Log-Excerpt of another participant student:Ja En: yes student:Er muss die Zahl 320 als Bruch umwandeln entweder 320/1 oder soo un dann den Hauptnenner rechnen. En: he needs to extend the number 320 to the fraction 320/1 or so and then compute the common denominator WOz:Richtig! Du hast den Fehler gefunden! Correct, you’ve found the error WOz: Nein, es wurde nicht richtig gerechnet/argumentiert. En: no the solution is incorrect student: lies dir die Aufgabe noch mal genau durch. En: please read the problem again En: Woz:Nein En: no WOz:Warum kann das errechnete Ergebnis nicht stimmen? En: why can the result not be correct? WOz:Korrigiere nun (in deinem Eingabefenster) den ersten fehlerhaften Schritt und führe die Berechnungen zu Ende. [...] En: now correct the first incorrect step and complete the computation WOz:Hast du Fragen? En: do you have questions? student:nein En: no student:keine ahnung En: no idea WOz:Warum kann das errechnete Ergebnis nicht stimmen? En: why can the result not be correct? WOz:Wie würdest du vorgehen, um den fehlerhaften Schritt zu korrigieren? Beschreibe in Worten. En: what would you do to correct the wrong step? describe in your own words. student:weil ulli die 320 liter auch in einen bruch umrechnen muss En: because ulli needs to transform the 320 liter into a fraction student:Also ich würde die 320/1 mit der 11/2 zusammen auf den Hauptnenner bringen dann das minus rechnen. En: well, I’d compute the common denominator of 320/1 and 11/2 and then substract WOz:Wo ist der Fehler? [...] En: where is the error? student:Schritt 3;weil ulli die 320 liter auch in einen bruch umrechnen muss En: step 3; because ulli needs to transform the 320 liter into a fraction WOz:Richtig, versuche dies nun rechnerisch umzusetzen! En: correct, now try to compute this WOz:Richtig! Du hast den Fehler gefunden! correct! you found the mistake WOz:Korrigiere nun (in deinem Eingabefenster) den ersten fehlerhaften Schritt und führe die Berechnungen zu Ende. [...] Please correct (in the input window) only the first incorrect step En: WOz:Was genau hat er falsch gemacht? En: what exactly did he make wrong? student:Schritt 3;er hat die 320 liter nicht in einen bruch umgerechnet. En: step3; he didn’t transform 320 liter to a fraction student: wie bringt man es wieder auf den Hauptnenner? En: how is the common denominator computed? 66 examples makes a difference to learning and whether highlighting errors helps students learn from those errors. Their empirical studies in which no help was provided showed some learning benefit of erroneous examples, but unlike the less ambiguous Siegler et al results, the benefit they uncovered was only for learners with strong prior knowledge and for far transfer learning. Research in other domains, such as medical education, has shown benefits of erroneous examples in combination with elaborate feedback in the acquisition of problem-solving schemata. More relevant to the work presented in this paper is Ohlsson’s theory (Ohlsson 1996) argues that errors occur due to overgeneralization (applying rules to situations where they do not apply). Error-detection requires declarative knowledge (e.g.knowledge of rules) in the domain. The error causes a conflict between this knowledge which the learner believes to be true and what the learner perceives as the current situation. The way to avoid errors is by specializing knowledge structures to trigger only in the situations where they apply. Ohlsson distinguished between declarative knowledge (knowing that) and practical knowledge (knowing how), which he defines as the knowledge required to choose the appropriate action in a perceive-decide-act cycle. The contribution of our work are empirical studies that explicitly tackle this dissociation, in particular, in the domain of fractions. This in turn can inform the design of erroneous examples and intruction not only in the context of technology-enhanced learning, which we focus on, but in general. WOz:Wie würdest du vorgehen, um den fehlerhaften Schritt zu korrigieren? En: How would you proceed in order to correct the incorrect step? student:Schritt 3;ich würde aus den 320 liter 160/2 machen und dann die 11/2 davon abziehen En: step3; I’d transform 320 liter to 160/2 and then substract 11/2 WOz: Wie würdest du vorgehen. Erkläre mit deinen eigenen Worten. Ohne genaue Rechnungen. En: how would you proceed? explain in your own words. without exact computations. WOz:Hast du Fragen? En: do you have questions? student:Schritt 3; ich würde die 320 liter nehmen und in 160/2 liter umwandeln, dann die 5 1/2 liter in 11/2 liter um wandeln und dann die 11/2 liter von den 160/2 liter abziehen so wäre das ergebnis: 149/2 liter En: step 3; I’d take the 320 liter and transform it to 160/2 liter, then transform the 5 1/2 liter into 11/2 liter, and then substract 11/2 liter from 160/2 liter with the result 149/2 liter. In this interaction the student found the mistake (subtraction of two fractions with different denominators without first computing the common denominator) and had an idea how to correct the error (expansion of 320 to a fraction with the denominator two), which means he/she was a step ahead but still could not complete the computation of the common denominator, i.e., did not fully understand the principle of expanding fractions to equal denominators.. Would understanding the principle conceptually allow students to perform the necessary actions automatically? What exactly it is that prevents them from correcting the error once they recognize it? Conclusion Our goal is a cognitive tool that supports learning from error, in particular from erroneous examples and that increases monitoring alert. As the results show, the tool needs to adapt to the student’s mastery level for sequencing and metacognitive help provision. This article describes results on our way to support students in developing the meta-cognitive skills of error detection and error correction in ACTIVE M ATH. Related Work Erroneous examples in mathematics have rarely been investigated or used as a learning intervention, either within a technology-enhanced learning (TEL) system or within the classroom. Overall, the related previous studies did not target adaptation by the technology. The empirical results (sometimes inconclusive) evidence that studying errors can promote student learning (Borasi 1994; Siegler 2002; Curry 2004; Grosse & Renkl 2004; Monthienvichienchai & Melis 2005; Grosse & Renkl 2007; Siegler & Chen 2008). The skill of correcting errors was not addressed before. A controlled comparison of the study of correct and incorrect examples was done by Siegler and colleagues (Siegler 2002; Siegler & Chen 2008). They investigated whether self-explaining both correct and incorrect examples is more beneficial than self-explaining correct examples only. They found that when students studied and self-explained both correct and incorrect examples they learned better. They hypothesized that self-explanation of correct and erroneous examples strengthened correct strategies and weakened incorrect problem solving strategies, respectively. Grosse and Renkl studied whether explaining both correct and incorrect Acknowledgement This work was supported by Deutsche Forschungsgemeinschaft in the project ME 1136/7-1. References Borasi, R. 1994. Capitalizing on errors as ”springboards for inquiry”: A teaching experiment. Journal for Research in Mathematics Education 25(2):166–208. Curry, L. 2004. The effects of self-explanations of correct and incorrect solutions on algebra problem-solving performance. In D. Gentner, K. F., and Regier, T., eds., 26th Annual Conference of the Cognitive Science Society, 1548. Mahwah, NJ: Erlbaum. Grosse, C., and Renkl, A. 2004. Learning from worked examples: What happens if errors are included? In Gerjets, P.; Elen, J.; Joiner, R.; and Kirschner, P., eds., Instructional design for effective and enjoyable computer-supported learn- 67 ing. Tuebingen: Knowledge Media Research Center. 356– 364. Grosse, C., and Renkl, A. 2007. Finding and fixing errors in worked examples: Can this foster learning outcomes? Learning and Instruction 17:612–634. Melis, E., and Kriesell, D. 2009. Effects of erroneous examples, results of a preliminary school experiment. In V. Dimitrova, R. Mizoguchi, B. d. B., and Graesser, A., eds., AIED 2009, volume 200 of Frontiers in Artificial Intelligence and Applications, 578–580. IOS press. Monthienvichienchai, R., and Melis, E. 2005. Implementing courseware to support learning through real-world erroneous examples: Student’s perceptions of tertiary courseware and obstacles to implementing effective delivery through vle. In Remenyi, D., ed., Proceedings of European Conference on eLearning (ECEL-2005), 281–289. Academic Conferences International. Ohlsson, S. 1996. Learning from performance errors. Psychological Review 103:241–262. Siegler, R., and Chen, Z. 2008. Differentiation and integration: Guiding principles for analyzing cognitive change. Developmental Science 11:433–448. Siegler, R. 2002. Microgenetic studies of self-explanation. In Granott, N., and Parziale, J., eds., Microdevelopment, Transition Processes in Development and Learning. Cambridge University Press. 31–58. Tsamir, P., and Tirosh, D. 2003. In-service mathematics teachers’ views or errors in the classroom. In International Symposium : Elementary Mathematics Teaching. Tsovaltzi, D.; Melis, E.; McLaren, B.; Dietrich, M.; Goguadze, G.; and Meyer, A.-K. 2009. Erroneous examples: A preliminary investigation into learning benefits. In Ulrike Cress, Vania Dimitrova, M. S., ed., European Conference for Technology-Enhanced Learning, EC-TEL 2009, LNCS 5794, 688–693. Springer-Verlag. Tsovaltzi, D.; Melis, E.; McLaren, B.; Meyer, K.; Dietrich, M.; and Goguadze, G. 2010. Learning from erroneous examples: When and how do students benefit from them? In , ed., EC-TEL 2010, volume - of LNCS, –. Springer-Verlag. vanLehn, K.; Graesser, A.; Jackson, G.; Jordan, P.; and C.P.Rose. 2007. When are tutorial dialogues more effective than reading? Cognitive Science 31:3–62. 68