Systems, methods, apparatuses, and computer program products for inferring the stress valence of an individual from sensor data are provided. One method includes collecting a first set of data from sensor(s) of user device(s), collecting a second set of data including a partial or complete ecological momentary assessment (EMA) response from a user, establishing a set of physiological time-series data for the user based on the first set of data and the second set of data, identifying habit information of the user based on the first set of data. Based on the first set of data and the habit information, detecting a potential trigger point for sending a subsequent EMA to the user, and, at the time of the potential trigger point, calculating an estimate of a stress valence value associated with the subsequent EMA for which an EMA response was at least partially not received.
