RULES Patty Nordstrom Hien Nguyen
"Cognitive Skills are Realized by Production Rules"
Cognitive Skills Cognitive skills are any mental skills that are used in the process of acquiring knowledge; these skills include reasoning, perception, and intuition. Cognitive skills refer to those skills that make it possible for us to know.
Production Rules • Production rules constitute a framework for understanding human cognition • Production rules are if-then statements or condition-action pairs Ex. If it snows, then I'll go skiing Ex. If status='OK' and type=3 then count+1
Property of Rules • Representation • Computational • Psychological • Practical
Representational Power • Represent general information about the world • Represent information about how to do things in the world • Represent linguist regularities • Inferences such as modus ponens
Computational Power • Problem solving • Searching, space, heuristics • Planning • Sequence of rule • Decision making • Learning • Acquisition, modification, application • Language
Psychological Plausibility • Rule-based systems can account for different types of learning • power law of practice • conditioning
Practical Applicability Learning consists of rules so how can this be applied to helping students better acquire rules • Computer tutors • Rule based cognitive systems • ACT & ACT-R (Adaptive Control of Thought—Rational) • SOAR (Soar is used by AI researchers to construct integrated intelligent agents and by cognitive scientists for cognitive modeling)
Frameworks • Frameworks – set of constructs that define important aspects of cognition. • Frameworks – cannot make predictions, but you can add assumptions to make theories
Theories • Theories still cannot make precise predictions • Add assumptions about a specific situation and it is a model of that situation
Models • Models - theories with assumptions about its application to a specific situation • Many models possible within a theory • Production system are theories of human cognition
Cognitive Architectures • Cognitive architectures are proposals about the structure of human cognition • Cognitive architecture tries to provide a complete, if abstract, specification of a system • Production system are theories of human cognition because they are architectures
Features of Production Systems • Each production rule is a modular piece of knowledge (a well-defined step of cognition) • Complex cognitive processes: • String a sequence of rules • Writing to working memory (goal setting, etc) • Reading from working memory • Rules are condition-action asymmetrical • Rules are abstract & apply in many situations
How do production systems operate? • Pattern matching • Production’s condition vs. contents of working memory • Conflict resolution • Firing a production -> CYCLE
How to write a production system model? • Write a set of production rules to perform the task • For AI, production systems are used as programming formalisms • Precise, complete theories of tasks • Without cognitive modeling
Examples • A production system for addition • Various production system architectures: • PSG: first production system implemented as a computer program • OPS systems • Efficient pattern matching and conflict resolution • ACT systems: ACTE, ACT*, ACT-R • Include a separate declarative representation • SOAR system
ACT-Rhttp://act-r.psy.cmu.edu/about/ • A cognitive architecture: a theory about how human cognition works. • A framework • A cognitive skill is composed of production rules.
ACT-R: Model and Method
ACT-R: Application
ACT-R: Components
Are rules psychologically real? • Appropriateness of rules in describing skilled behavior • Ability to predict the details of that behavior
Problems • Is ACT-R the right production system theory? • Assumption: production system framework is the right way to think about cognitive skill.
Implementation Level Problems • Algorithm level vs. Implementation level • High-level programming language vs. machine level implementation • It is difficult to identify what is going on at the implementation level. • Uniqueness: which implementation is the underlying internal structure? • Discovery: which implementation matches the behavior?
Implementation Level Problems • Uniqueness Problem • Neural approach: use neural-like computations • Discovery Problem • Rational approach -> ACT-R • Cognition is adapted to environment structure: • Memory • Categorization • Causal inference • Problem solving
Intelligent Tutoring Systems • Previously • CAI vs. ICAI • Impractical • Costly • Time • No established paradigm for enabling students to acquire knowledge. • Now • Cost reduced, advances in AI and cognitive psychology -> shorter time, advances in cognitive science -> instructional design implications
knowledge of the domain knowledge of the learner knowledge of teacher strategies http://coe.sdsu.edu/eet/Articles/tutoringsystem/start.htm ITS Model
What an ITS must do • accurately diagnose students' knowledge structures, skills, and styles • diagnose using principles, rather than preprogrammed responses • decide what to do next • adapt instruction accordingly • provide feedback http://coe.sdsu.edu/eet/Articles/tutoringsystem/start.htm
ACT-based approach to intelligent tutoring • Goal structure • Instruction in Context • Immediacy of Feedback • Examples: the Geometry Tutor, the LISP Tutor
Video: Reading Tutor • http://www.cs.cmu.edu/~listen/videos/1998_video_10_min/
Question?
Design Scenario • In your group, discuss the design of an intelligent tutoring system that teaches HTML to highschool students. Please use the ACT-R cognitive architecture and discuss the use of production rules in your design. • FOCUS: • The degree of learner control • Individual vs. collaborative learning • Situated learning • Intelligent Tutor System vs. regular Computer-Aided Instruction
References • http://act-r.psy.cmu.edu/about/ • http://en.wikipedia.org/wiki/ACT-R • http://coe.sdsu.edu/eet/Articles/tutoringsystem/start.htm • http://www.cs.cmu.edu/~listen/videos/1998_video_10_min/lis06.mpg • http://act-r.psy.cmu.edu/papers/Lessons_Learned.html • http://www.ncrel.org/sdrs/areas/issues/content/cntareas/reading/li1lk23.htm • http://www.audiblox2000.com/cognitiveskills.htm • http://www.britannica.com/eb/article-9053169/modus-ponens-and-modus-tollens
