1. 1 Computer Group Engineering Department University of Science and Culture S. H. Davarpanah Davarpanah@usc.ac.ir

2. Expert Systems Task Areas cf. Jackson, Ch.11 'Heuristic Classification I‘, based on Clancey (1993), Hayes-Roth et al. (1983), Waterman (1986); for exact references see bibliography in Jackson

3. Task Areas of XPS  Tasks /Task Areas of Expert Systems What kinds or types of tasks do XPS perform? e.g. diagnosis, construction  Classification of XPS Task Types How can XPS be analyzed into different tasks or categories of tasks? - analysis vs. synthesis

4. Classification of XPS Tasks Generic Tasks in Expert Systems (XPS)  Analysis analytical view and treatment of domain or system behaviour; e.g. diagnostic problems  Synthesis constructive problem solving or constructive approach to generate system (behavior); e.g. construction problems (Clancey (1985), see Jackson, p.209 ff.)

5. Task Areas of Expert Systems System-Based View of XPS Tasks Analysis Tasks (Interpretation of System) – Diagnosis – Classification Synthesis Tasks (Construction of System) – Construction – Configuration – Design – Planning

6. Analysis Tasks Analysis Tasks (Diagnosis, Classification) determine specific solution element (diagnosis) based on a description of the system (symptoms or other descriptive facts) rules formulate connections between symptoms etc. and diagnostic class e.g. the medical expert system MYCIN for diagnosing bacterial infections e.g. tutoring systems like GUIDEON for diagnosing student’s mistakes

7. System Analysis Operations INTERPRET IDENTIFY PREDICT CONTROL MONITOR DIAGNOSE

8. Analysis Tasks INTERPRET analyze and interpret system (input, output, structure) IDENTIFY given input-output pairs, determine kind of system PREDICT predicting output for class of given inputs CONTROL determine inputs which achieve specific state/output MONITOR detect discrepant (faulty) behavior DIAGNOSE explain (faulty) behavior

9. Synthesis Tasks Synthesis Tasks (Construction, Configuration, Design, Planning) combine elements from a component (solution) space and check consistency of complete solution rules formulate constraints and extensions for partial solution, similar to planning e.g. the technical expert system R1/XCON to configure computer systems

10. CONSTRUCT SPECIFY DESIGN ASSEMBLE CONFIGURE PLAN System Synthesis Operations

11. CONSTRUCT Solution space is not pre-defined SPECIFY state constraints for any solution DESIGN generate arrangement of parts to satisfy constraints ASSEMBLE / MODIFY realize design by putting parts together CONFIGURE (Design) layout of design PLAN (Design) methods to assemble structure Expert Systems Synthesis Tasks

12. Interpretation Prediction Diagnosis Control Monitoring Planning Design Debugging and Repair Instruction (Hayes-Roth et al. (1983), see Jackson, p.208) Expert Systems – Tasks ANALYSIS SYNTHESIS

13. Expert Systems – Tasks 1 Interpretation forming high-level conclusions from raw data Prediction projecting probable consequences of given situations Diagnosis determining the cause of malfunctions in complex situations based on observable symptoms Design finding a configuration of system components that meets performance goals while satisfying a set of design constraints

14. Expert Systems – Tasks 2 Planning devising a sequence of actions that will achieve a set of goals given certain starting conditions and run-time constraints Monitoring comparing a system’s observed behavior to its expected behavior Debugging and Repair prescribing and implementing remedies for malfunctions Instruction detecting and correcting deficiencies in students’ understanding of a subject domain Control governing the behavior of a complex environment