1. A computer-readable medium or media comprising one or more sequences of instructions which, when executed by one or more processors, causes steps for recognizing a sequence of actions comprising: segmenting input sensor data into time frames; generating a feature for each time frame; for a time frame, selecting an action associated with a maximized value of an objective function that comprises a first set of feature-dependent models for intra-action transitions and a second set of feature-dependent models for inter-action transitions.