Knowledge Based Systems: A Critical Survey of Major Concepts, Issues, and Techniques

This Working Paper Series entry presents a detailed survey of knowledge based systems. After being in a relatively dormant state for many years, only recently is Artificial Intelligence (AI) - that branch of computer science that attempts to have machines emulate intelligent behavior - accomplishing practical results. Most of these results can be attributed to the design and use of Knowledge-Based Systems, KBSs (or ecpert systems) - problem solving computer programs that can reach a level of performance comparable to that of a human expert in some specialized problem domain. These systems can act as a consultant for various requirements like medical diagnosis, military threat analysis, project risk assessment, etc. These systems possess knowledge to enable them to make intelligent desisions. They are, however, not meant to replace the human specialists in any particular domain. A critical survey of recent work in interactive KBSs is reported. A case study (MYCIN) of a KBS, a list of existing KBSs, and an introduction to the Japanese Fifth Generation Computer Project are provided as appendices. Finally, an extensive set of KBS-related references is provided at the end of the report

Evidentiality in Dena'ina Athabaskan

Dena'ina evidentials are enclitics with a complex paradigmatic morphology. Their first component varies with person, while the second com- ponent varies with animacy and number, thus marking source and nature of knowledge. Although evidentiality in Dena'ina is not coded as an obligatory inflectional category on the verb, it is also not scattered throughout the gram- mar. The existence of an incipient inflectional evidential system demonstrates the ability of Athabaskan languages to innovate morphological structures outside the verb. The uniqueness of the Dena'ina system demonstrates the heterogeneity of Athabaskan grammar beyond the verb word

On the simulation of interactive non-verbal behaviour in virtual humans

Development of virtual humans has focused mainly in two broad areas - conversational agents and computer game characters. Computer game characters have traditionally been action-oriented - focused on the game-play - and conversational agents have been focused on sensible/intelligent conversation. While virtual humans have incorporated some form of non-verbal behaviour, this has been quite limited and more importantly not connected or connected very loosely with the behaviour of a real human interacting with the virtual human - due to a lack of sensor data and no system to respond to that data. The interactional aspect of non-verbal behaviour is highly important in human-human interactions and previous research has demonstrated that people treat media (and therefore virtual humans) as real people, and so interactive non-verbal behaviour is also important in the development of virtual humans. This paper presents the challenges in creating virtual humans that are non-verbally interactive and drawing corollaries with the development history of control systems in robotics presents some approaches to solving these challenges - specifically using behaviour based systems - and shows how an order of magnitude increase in response time of virtual humans in conversation can be obtained and that the development of rapidly responding non-verbal behaviours can start with just a few behaviours with more behaviours added without difficulty later in development

Learning Fault-tolerant Speech Parsing with SCREEN

This paper describes a new approach and a system SCREEN for fault-tolerant speech parsing. SCREEEN stands for Symbolic Connectionist Robust EnterprisE for Natural language. Speech parsing describes the syntactic and semantic analysis of spontaneous spoken language. The general approach is based on incremental immediate flat analysis, learning of syntactic and semantic speech parsing, parallel integration of current hypotheses, and the consideration of various forms of speech related errors. The goal for this approach is to explore the parallel interactions between various knowledge sources for learning incremental fault-tolerant speech parsing. This approach is examined in a system SCREEN using various hybrid connectionist techniques. Hybrid connectionist techniques are examined because of their promising properties of inherent fault tolerance, learning, gradedness and parallel constraint integration. The input for SCREEN is hypotheses about recognized words of a spoken utterance potentially analyzed by a speech system, the output is hypotheses about the flat syntactic and semantic analysis of the utterance. In this paper we focus on the general approach, the overall architecture, and examples for learning flat syntactic speech parsing. Different from most other speech language architectures SCREEN emphasizes an interactive rather than an autonomous position, learning rather than encoding, flat analysis rather than in-depth analysis, and fault-tolerant processing of phonetic, syntactic and semantic knowledge.Comment: 6 pages, postscript, compressed, uuencoded to appear in Proceedings of AAAI 9

Confronting a Monument: The Great Chief Justice in an Age of Historical Reckoning

The year 2018 brought us two new studies of Chief Justice John Marshall. Together, they provide a platform for discussing Marshall and his role in shaping American law. They also provide a platform for discussing the uses of American history in American law and the value of an historian’s truthful, careful, complete, and accurate accounting of American history, particularly in an area as sensitive as American slavery. One of the books reviewed, Without Precedent, by Professor Joel Richard Paul, provides an account of Chief Justice Marshall that is consistent with the standard narrative. That standard narrative has consistently made a series of unsupported and ahistorical claims about Marshall over the course of two centuries. The substantial errors contained in this standard narrative are exposed by another book, Supreme Injustice, by Professor Paul Finkelman, which reveals, in groundbreaking fashion, Chief Justice Marshall’s deep personal and professional commitment to, and investment in, the institution of American slavery. Chief Justice Marshall’s commitment to an institution that has been rejected by our law and by pervasive social norms should give his modern successors, attorneys, judges or students of the law, as well as citizens, substantial pause when relying upon Marshall as a posthumous authority and reference point in debates regarding contemporary legal subjects. Any other conclusion would countenance an unjustified double-standard when assessing American historical figures whose conduct we would condemn if perpetrated by historical figures from foreign nations

Dead Again: The Latest Demise of the Confrontation Clause

In Crawford v. Washington, the Supreme Court abandoned its Roberts “reliability” approach to the right of confrontation. The Court conceded that the Roberts decision had killed the Confrontation Clause by: (1) impermissibly tying the right of confrontation to the rule against hearsay; (2) inappropriately allowing pretrial determinations of reliability to replace actual cross-examination at trial; (3) relying too heavily on malleable, multi-factor balancing tests; and (4) completely failing to constrain judicial discretion. Since Crawford, however, the Court has decided Davis v. Washington and Michigan v. Bryant. Unfortunately, in the course of deciding those cases the Court has once again killed the Confrontation Clause. More specifically, the Court has developed yet another framework that incorporates every single one of Roberts’s flaws, including its failure to constrain judicial discretion. This Essay exposes the underlying reasons for the Court’s failure, offers a solution to the problem, and provides suggestions for the Court when deciding future cases that involve the constitutional rights of criminal defendants

A Picture’s Worth a Thousand Words: Conversational versus Eyewitness Testimony in Criminal Convictions

Scholars and practitioners alike share a widespread belief that the single greatest cause of wrongful conviction is erroneous eyewitness testimony. This conventional wisdom is almost certainly wrong. Conversational testimonydescribing earlier conversations or statements-is more common, more likely to be inaccurate, more likely to be believed by jurors, and more likely to produce irreversible errors than eyewitness testimony. Nonetheless, the dangers to the innocent posed by conversational testimony have been largely unrecognized. This Article highlights the case for further psychological and legal attention to conversational witnesses by comparing how the psychological processes and legal responses differ between eyewitness and conversational testimony. The Article concludes with implications for reform that may minimize the ongoing and unrecognized miscarriages of justice which result from erroneous conversational testimony

The Excited Utterance Paradox

Based on nothing more than John Henry Wigmore’s personal belief that a witness under the throes of excitement is unable to fabricate an untruthful statement, the excited utterance exception allows parties to present out-of-court statements to the jury or judge without any of the safeguards the judicial system uses to promote honest and accurate testimony. This Article collects and examines much of the scientific evidence bearing on Wigmore’s premise and identifies two paradoxical conclusions that undermine the exception. First, the premise itself is unfounded; science absolutely does not support the notion that a witness is incapable of lying while emotionally agitated. But, there is a second phenomenon at work that counteracts the premise (were it valid); witnesses under extreme emotional stress are unreliable observers and reporters of the events causing the stress. Thus, in the unlikely event that an occurrence was sufficiently stressful to impede the ability to lie, the stress would also interfere with the ability to perceive and describe the occurrence reliably. Based on this paradox, this Article concludes that the excited utterance exception is both broken and irreparable, and therefore recommends abandoning the excited utterance exception altogether