1. A computer-implemented method for determining a decision point in real-time for a data stream from a conversation, the method comprising: receiving, by a computing device, streaming conversational data; and determining, by said computing device, when to classify the streaming conversational data into one of thematic categories and labels from a predefined set, using a measure of certainty, by performing certainty calculations at a plurality of time instances during the conversation and by selecting a decision point in response to the certainty calculations, the decision point being based on accumulated conversational data available at different ones of the plurality of time instances.