A learning curve for tasks with cognitive and motor elements

This paper develops a new learning curve model that has cognitive and motor components. The developed model is fitted to experimental data of a repetitive manual assembly-and-disassembly task. The fits are compared to those of two other known models from the literature, which are the renowned power form learning curve and its aggregated version. The model developed in this paper performed the best. The fits of the models are evaluated using the mean squared error method. Furthermore, the developed learning curve model is investigated by incorporating it into the economic production quantity model, a topic which has been frequently studied by researchers. The results show that assuming an inappropriate learning curve may produce biased inventory policies by over- or underestimating production rates and consequently inventory levels.

► An aggregated learning curve for cognitive and motor learning is developed.
► The learning curve is fitted to empirical data of a manual assembly task.
► The fits were better than those of two prominent models.
► The learning curve was applied to an inventory situation.
► Results showed that using the wrong learning curve biases inventory policies.