1. Field of the Invention
The present invention relates to systems and methods for assessing call center performance and, in particular, to systems and methods that allow the performance and current and potential levels of automation of a call center to be quantified.
2. Discussion of the Related Art
Telephone user interfaces are the most widespread class of human-computer interfaces. Introduced more than a decade ago, touch-tone interactive voice response (IVR) systems were adopted enthusiastically in many call-centers and promised to provide customer service efficiently. However, calling customers (callers) have exhibited antipathy towards touch-tone IVR systems, viewing them as difficult to use. Further aggravating the callers is the fact that they often endure long waiting times before they can speak to live agents. This dichotomy is not surprising considering that most call-centers focus on minimizing operating costs and that usability and its impact on call-center operations are poorly understood.
Since touch-tone IVR systems have been deployed for more than a decade, a significant body of know-how on IVR systems has accumulated in the industry. Except for recent attempts to define a style guide for (telephone) speech applications, as in Balentine, B. and D. P. Morgan, How to Build A Speech Recognition Application, 1999, San Ramon, Calif, Enterprise Integration Group, and to introduce universal commands in speech-enabled IVR systems, as in Cohen, M., Universal Command for Telephony-Based Spoken Language Systems, SIG-CHI Bulletin, 2000, 32(2), pp. 25-30, this body of knowledge is not well documented. The prevalence of usability problems in deployed IVR systems suggests that designing good telephone interfaces is difficult and usability engineering methods for telephone interfaces are not well developed.
Another area of related work is research on spoken dialog systems, an important application of speech recognition technology. Spoken dialog systems allow the caller to communicate with a system in a spoken dialog, not necessarily over the telephone. Many research articles on spoken dialog systems have been published, e.g., Stallard, D., Talk""N""Travel: A Conversational System for Air Travel Planning, in Applied Natural Language Processing ANLP, 2000, Seattle, Wash.; Peckham, J., A new generation of spoken language systems: recent results and lessons from the SUNDIAL project, in European Conference on Speech Communication and Technology EUROSPEECH, 1993, Berlin (Germany): European Speech Communication Association; Levin, E. and R. Pieraccini, CHRONUS: The Next Generation, in ARPA Workshop on Spoken Language Technology, 1995, Austin (Tex.): Morgan Kaufmann Publishers, Inc.; Bennacef, S., et al., Dialog in the RIALTEL telephone-based system, in International Conference on Spoken Language Systems ICSLP, 1996, Philadelphia, Pa.; and Lee, C. H., et al., On Natural Language Call Routing, in Speech Communications, 2000, 31, pp. 309-320.
Previous work on spoken-dialog system evaluation focused on quantifying the performance of the underlying technologies, e.g., Chang; H., A. Smith, and G. Vysotsky, An automated performance evaluation system for speech recognizers used in the telephone network, in International Conference on World Prosperity Through Communications, 1989; and Pallett, D. S., et al., 1993 Benchmark Tests for the ARPA Spoken Language Program, in ARPA Workshop on Spoken Language Technology, 1994, Princeton (N.J.): Morgan Kaufmann Publishers, Inc.
Some studies have evaluated the usability of telephone interfaces based on task completion rates and post-experimental questionnaires, e.g., Edwards, K., et al., Evaluating Commercial Speech Recognition and DTMF Technology for Automated Telephone Banking Services, in IEEE Colloquium on Advances in Interactive Voice Technologies for Telecommunication Services, 1997. More recently, PARADISE was introduced as a xe2x80x9cconsistent integrative framework for evaluationxe2x80x9d of spoken language systems, as described in Walker, M. A., et al., PARADISE: A Framework for evaluating spoken dialogue agents, in 35th Annual Meeting of the Association of Computational Linguistics, 1997, Madrid: Morgan Kaufmann Publishers, Inc. Basically, PARADISE provides a method to identify measures that predict user satisfaction well, from the large set of measures that have been used in the field. However, this work does not address the cost for the call center, nor does it provide any guidance for telephone interface redesign.
The present invention overcomes the deficiencies of earlier systems by presenting a methodology for evaluating both usability and cost-effectiveness of telephone user interfaces. The assessment methodology of the present invention, and the various inventive techniques utilized within that methodology, provide usability practitioners with tools to identify and quantify usability problems in telephone interfaces, and provide call-center managers with the business justification for the cost of usability-improvement engineering.
The present invention relates to a system for analyzing an automated response system of a call center, to enable assessment of the call center. Of course, although the descriptions herein relate to call centers that process telephone calls, other types of contact centers other than call centers are within the realm of the present invention, including (but not limited to) Internet-based contact centers where customers contact a company""s contact center via the Internet using known ways for transmitting messages and information via the Internet.
According to one aspect of the present invention, there is provided a method of determining a complete sequence of events occurring within an interactive voice response (IVR) system of a call processing center, the IVR system being operable to automatically accept calls from callers and respond to input from the callers. The method comprises the steps of: modeling a call flow of the IVR system as a non-deterministic finite-state automaton; splitting a recording of plural calls to the call processing center, such that each of the plural calls to the call center is in one audio file; for a plurality of calls, detecting a complete sequence of DTMF and/or speech input to the IVR system; for a plurality of calls, detecting selected prompts issued by the IVR system; and for a plurality of calls, inputting the detected sequence of DTMF and/or speech input as well as the detected prompts issued by the IVR system into the finite-state automaton to determine a call-event sequence for that call. The call-event sequence includes information regarding how that call left the IVR system.
According to another aspect of the present invention, there is provided an apparatus for determining a complete sequence of events occurring within an interactive voice response (IVR) system of a call processing center, the IVR system being operable to automatically accept calls from callers and respond to input from the callers. The apparatus comprises: means for modeling a call flow of the IVR system as a non-deterministic finite-state automaton; means for splitting a recording of plural calls to the call processing center, such that each of the plural calls to the call center is in one audio file; means for, for a plurality of calls, detecting a complete sequence of DTMF and/or speech input to the IVR system; means for, for a plurality of calls, detecting selected prompts issued by the IVR system; and means for, for a plurality of calls, inputting the detected sequence of DTMF and/or speech input as well as the detected prompts issued by the IVR system into the finite-state automaton to determine a call-event sequence for that call. The call-event sequence includes information regarding how that call left the IVR system.
According to yet another aspect of the present invention, there is provided a system for determining a complete sequence of events occurring within an interactive voice response (IVR) system of a call processing center, the IVR system being operable to automatically accept calls from callers and respond to input from the callers. The system is operable to: model a call flow of the IVR system as a non-deterministic finite-state automaton; split a recording of plural calls to the call processing center, such that each of the plural calls to the call center is in one audio file; for a plurality of calls, detect a complete sequence of DTMF and/or speech input to the IVR system; for a plurality of calls, detect selected prompts issued by the IVR system; and for a plurality of calls, input the detected sequence of DTMF and/or speech input as well as the detected prompts issued by the IVR system into the finite-state automaton to determine a call-event sequence for that call. The call-event sequence includes information regarding how that call left the IVR system.
According to still another aspect of the present invention, there is provided a computer program product embodying a program for implementing a method of determining a complete sequence of events occurring within an interactive voice response (IVR) system of a call processing center, the IVR system being operable to automatically accept calls from callers and respond to input from the callers. The computer program product comprising: code for modeling a call flow of the IVR system as a non-deterministic finite-state automaton; code for splitting a recording of plural calls to the call processing center, such that each of the plural calls to the call center is in one audio file; code for, for a plurality of calls, detecting a complete sequence of DTMF and/or speech input to the IVR system; code for, for a plurality of calls, detecting selected prompts issued by the IVR system; and code for, for a plurality of calls, inputting the detected sequence of DTMF and/or speech input as well as the detected prompts issued by the IVR system into the finite-state automaton to determine a call-event sequence for that call. The call-event sequence includes information regarding how that call left the IVR system.
These and other objects, features, and advantages of the present invention will be apparent from the following description of the preferred embodiments considered in conjunction with the corresponding drawings.