The Variance Learning Curve

The expansive learning curve literature in operations management has established how various facets of prior experience improve average performance. In this paper, we explore increased cumulative affects performance variability or consistency. We use a two-stage estimation method heteroskedastic model to examine the relationship between and among paramedics at London Ambulance Service. find that, for with lower experience, an increase 500 jobs reduces variance task completion time by 8.7%, addition improving times 2.7%. Similar results on curve, diminishing impact additional curve. provide evidence base benefits service systems. Our findings imply that are substantially underestimated if consistency effect is ignored. Specifically, our estimates indicate queue lengths (or wait times) might be overestimated as much 4% ignoring Furthermore, suggest previously drivers productivity should revisited they affect consistency, This paper was accepted Charles Corbett, management.