Devices, systems, and methods obtain sensor data that were generated by a plurality of sensors; obtain event data that include occurrences of an event; calculate first characteristics of the sensor data that were generated by the plurality of sensors within a temporal range of an occurrence of the event; identify, in the sensor data, sensor data that were generated by the plurality of sensors within the temporal range of at least one other occurrence of the event based on the first characteristics; calculate second characteristics of the sensor data that were generated by the plurality of sensors within the temporal range of the at least one other occurrence of the event, normalize at least some of the sensor data based on the first characteristics and on the second characteristics, thereby generating normalized sensor data, and train a machine-learning model based on the normalized sensor data.