14. A system comprising: one or more processors; and memory storing instructions that, when executed by the one or more processors, cause the system to: determine a change of an adapted speech-recognition model from an initial speech-recognition model based on speech-recognition performance data for one or more users; and identify, based on the determined change, a candidate user of the one or more users to use the adapted speech-recognition model.
16. The system of claim 14 , the memory storing instructions that, when executed by the one or more processors, cause the system to: perform a plurality of discriminative training processes to make a plurality of discriminative adjustments to a plurality of system-recognition models and recognition algorithms used by a speech-recognition processor.