Teaching system dynamics and discrete event simulation together: a case study

Abstract

System dynamics (SD) and discrete event simulation (DES) follow two quite different modeling philosophies and can bring very different but, nevertheless, complimentary insights in understanding the same ‘real world’ problem. Thus, learning SD and DES approaches requires students to absorb different modeling philosophies usually through specific and distinct courses. We run a course where we teach model conceptualization for SD and DES in parallel and, then, the technical training on SD and DES software in sequential order. The ability of students to assimilate, and then put into practice both modeling approaches, was evaluated using simulation-based problems. While we found evidence that students can master both simulation techniques, we observed that they were better able to develop skills at representing the tangible characteristics of systems, the realm of DES, rather than conceptualizing the intangible properties of systems such as feedback processes, the realm of SD. Suggestions and reflections on teaching both simulation methods together are proposed.

Keywords:

• System dynamics
• discrete event simulation
• OR education
• hybrid simulation

Notes

Please note this paper has been re-typeset by Taylor & Francis from the manuscript originally provided to the previous publisher.

1. Two markers with particular DES expertise (markers 1 and 2) shared the marking of part one and calibrated their marks by swapping three marked assignments and blind re-marking each one. After calibration there was found to be no significant differences in assessment scores and feedback comments were in alignment. A third marker with particular SD expertise (marker 3) marked part two of the assignment and a fourth marker second-marked a sample of the assignments to ensure consistency in the marking process. The assignments were further moderated by markers 2 and 3 s-marking the part of the assignment that they did not mark directly. A selection of the assignments was then moderated by an external examiner from a different University as per University policy. Both the second marking and external moderation assured consistency in marking levels across the two parts of the assessment. The marking schemes [based upon the modeling processes as suggested in Robinson (2014) and Sterman’s (2000) textbooks, as displayed in Figure 1] were used to divide the modeling process into the different categories for which general strengths and weaknesses across students work were noted down.