3. The method of claim 1 , wherein processing the input signal in accordance with the difference value comprises: adjusting the plurality of scores based on the difference value; and using the adjusted scores to update the speech recognition model.
3. The method of claim 1 , wherein processing the input signal in accordance with the difference value comprises: adjusting the plurality of scores based on the difference value; and using the adjusted scores to update the speech recognition model. 4. The method of claim 3 , further comprising: applying to the input signal a cepstrum transformation; and generating a mel-frequency cepstral representation comprising mel-frequency coefficients from the cepstrum transform representation of the input signal.