11. A method comprising: determining a partial dialog state for a turn based in part on user input associated with the turn; using a discriminative model to update the partial dialog state for a current turn based in part on the partial dialog state associated with the turn, wherein the partial dialog state is a time ordered sequence of an estimated user goal; and determining a dialog state based in part on the partial dialog state at the current turn as part of tracking a user goal.
11. A method comprising: determining a partial dialog state for a turn based in part on user input associated with the turn; using a discriminative model to update the partial dialog state for a current turn based in part on the partial dialog state associated with the turn, wherein the partial dialog state is a time ordered sequence of an estimated user goal; and determining a dialog state based in part on the partial dialog state at the current turn as part of tracking a user goal. 15. The method of claim 11 , further comprising updating the partial dialog state by determining which filled slots remain relevant in the current turn.