The term used for the series of three comparative studies of extrapolation methods organized by Spyros Makridakis, starting with the 1,001 time-series competition in Makridakis et al. (1982) and including Makridakis et al. (1993) and Makridakis and Hibon (2000). In each study, a number of different experts prepared extrapolations for holdout data. The accuracies of the various methods were then compared by the study’s lead author. Raw data and information about these competitions can be found on the Researchers and Practitioners pages of this site.