A practical guide for operational validation of discrete simulation models

Abstract

ABSTRACT. As the number of simulation experiments increases, the necessity for validation and verification of these models demands special attention on the part of the simulation practitioners. By analyzing the current scientific literature, it is observed that the operational validation description presented in many papers does not agree on the importance designated to this process and about its applied techniques, subjective or objective. With the expectation of orienting professionals, researchers and students in simulation, this article aims to elaborate a practical guide through the compilation of statistical techniques in the operational validation of discrete simulation models. Finally, the guide's applicability was evaluated by using two study objects, which represent two manufacturing cells, one from the automobile industry and the other from a Brazilian tech company. For each application, the guide identified distinct steps, due to the different aspects that characterize the analyzed distributions.

<b>Human factors in an automotive discrete event simulation model

“…The simulation computational model was constructed using the method proposed by Leal, Costa, Montevechi, Almeida, and Marins (2011). The method presents the phases of a simulation project in which three models must be developed:…”

“…Hence, current study will use the methods by Leal et al (2011) and Baines et al (2004) to conduct the simulation project associated with the insertion of human factors. As indicated earlier, usually humans are considered 'machines' in simulation models with default behaviors during the simulation time, with no distinctions in human behavior between the different scenarios.…”

“…After defining the human factor to be analyzed and determining how to insert it into the simulation model, we were able to develop the model within the method proposed by Leal et al (2011).…”

“…Statistical validation was conducted with the method proposed by Leal et al (2011). First, a normality test to simulated and observed data was applied.…”

“…According to Leal et al (2011), when variances are different, it is necessary to use the SmithSatterthwaite's method before the application of the T-test. Smith-Satterthwaite's method adjusts the degrees of freedom in relation to samples´ variance difference.…”