Abstract: A common problem faced by speech dialog systems is that they have to serve users with varying degrees of experience of such a system in an optimal manner. The invention relates to a speech dialog system that differentiates between inexperienced and experienced users and generates speech prompts that are adapted accordingly. The system is able to differentiate between inexperienced and experienced users, issuing a detailed speech prompt to the former and an abbreviated speech prompt to the latter. According to the invention, the speech dialog system initialises a dialog step using an abbreviated speech prompt. If the system user does not react to the abbreviated speech prompt after a specified time (recognition timeout), a detailed speech prompt is issued. Thus both types of speech prompts are issued for each dialog step and are available to the system user for selection. The user can therefore always select the type and manner of dialog he or she requires.

Abstract: Problems frequently occur in particular in the addition of voice enrollments (speech patterns, with which the user himself can supplement the vocabulary of the speech recognition system) to broad word lists (dynamic vocabulary). For this reason, when the speech recognition system is in an expansion mode, the speech pattern expressed by the user is associated as new voice enrollment to the existing recognizer vocabulary of the speech recognition system. Herein the assignment should however be only preliminarily in a first step. The new speech pattern is intermediate stored in a memory. The recognizer is supplied with this intermediate stored pattern for a repeated recognition process, wherein this repeated process occurs not only on the basis of the preliminarily expanded recognizer vocabulary but also on the basis of the system commands.

Abstract: In the case of vary large vocabulary, such as for example a list with all cities in Germany, there is the problem, that the addition of other words, which are activated parallel to this list during recognition, leads to a higher danger of a mix-up. If the recognition result cannot be associated with sufficient confidence with an element from a vocabulary list, then the user of the system is presented with the recognition result for confirmation thereof. Prior to the presentation of the system user with the recognition result a temporary vocabulary is formed, in which first that element is removed from the vocabulary list, of which the correct recognition is to be confirmed by the user. The recognizer processes this speech input on the basis of the temporary vocabulary as well as on the basis of the system commands and selects therefrom as recognition result at least one element.

Abstract: Due to the large vocabulary to be recognized, it is presently not possible in many commercially available speech recognition systems to identify, with the desired good recognition results, commands in parallel to the list elements (mostly recorded as dynamic vocabulary). It is now proposed that the speech pattern supplied to the speech recognition system by the user is intermediate stored. Parallel thereto, the at least one element selected from the list by the speech recognizer is merged in a first recognition step with the system command to form a temporary recognizer vocabulary. After the production of this temporary recognizer vocabulary, subsequently the intermediate stored speech input is newly submitted to the recognizer, wherein this now forms the basis of this temporary recognizer vocabulary.

Abstract: In a process for operating a speech dialog system, which adapts its to the speech quality of different speakers, the speech recognizer estimates the probability of a correct recognition of the user response or expression, in that it consults for estimation a confidence gage by means of which the words or phrases potentially contained in the speech response or expression are assigned a confidence value. One of the particularly preferred solutions of the inventive task are comprised in that for those speakers which are difficult for the speech dialog system to understand, it accepts in certain cases repetitions of the same user responses which, by themselves, would not be acceptable. A further advantageous solution is comprised therein, that the confidence threshold is selected depending upon the actual current dialog step.