In our survey of erroneous results (section 4.2), we found that the wrong sentences included in the speech data. We concluded that such causes errors because acoustic parameters and word trigram models do not correspond. To counter this, we modified the recognition algorithm, based on the following techniques. As is considered to be one word, it can be recognized, and thus, the trigram probability can be calculated to skip it. For example, when we see that w1 = in our calculation of , we calculate instead. And if we calculate , and , we set to .
This algorithm raised the sentence recognition rate to 71.6% as opposed to 66.7% with no such procedure for the SD case. Furthermore, a great improvement was found for the SI case (61.7% as opposed to 0.0% with no such procedure).