Page 144 - Getting the Picture Modeling and Simulation in Secondary Computer Science Education

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Chapter 6
— that is, within computer science lessons, as their first encounter with modeling. Student S11 was satisfied with the model, “because the model works the way I wanted, and the results, of course I’m happy with. Because you can do something with it, say something about it.” When asked about being convinced about their model, student S2 replied, “I don’t think this would happen like this for real. But I wouldn’t know what I’d need to improve.” Student S4 commented their model, “we saw of course that the program, running once, that everyone escaped, so it was like, it worked”; then went on to say, “but I think we were happy it worked, and yeah, maybe it is a suboptimal solution” and finally concluded, “if it works and it’s somewhat realistic, then we find it all right.” Student S3 elucidated, “Yeah, we were happy when everyone who heard the alarm just really went outside. Not through the wall but just through a doorway.” However, student S3 doubts this model is sufficiently realistic to be useful and would first need the people in the model to react to each other and to move more realistically. Student S6 commented their model, “I find that for the most part it corresponds [to reality], but if you look at the small details, we didn’t find them relevant and they don’t correspond in my opinion.” When asked when they would consider their model a success, student S6 replied, “when people stay alive for a longer period of time, it succeeded” and went on to comment, “with the assumptions we made and the stuff we looked up, I’m quite happy with the result.”
Two groups were not confident. Student S9 commented, “I know of course that this is not 100% correct, that it isn’t exactly realistic. So I think to myself, can you really do something with it — that a cheese producer would really use this to determine his sale strategy, I doubt it.” Student S7, when asked about being convinced about their model, replied, “Not at all. Well, it’s the small things, I don’t know, it doesn’t work the way I was taught it works” and went on to elaborate that nobody actually knows about electrons for certain, and that the notion of an electron as accepted in modern science is also only a model.
6.5 Conclusion and Discussion
In this section we present our findings and reflect on them.
6.5.1 Findings
In answering our first research question — How can the students’ understanding
of model verification and validation be portrayed in terms of validation techniques