A data processing method is described. A processor provides different training data sets to a plurality of graphics processing units (GPUs), respectively. The processor controls the plurality of GPUs to generate respective sets of modification parameters by performing respective training processes in a parallel manner using respectively managed versions of a predictive model according to the corresponding training data sets. The processor controls the plurality of GPUs to exchange, before completion of the respective training processes, at least a portion of the sets of modification parameters that have been generated by the plurality of GPUs. The processor also causes the plurality of GPUs to modify the respectively managed versions of the predictive model according to at least the portion of the sets of modification parameters exchanged among the plurality of GPUs.