Skill Acquisition and Expertise
ACT-R
(Anderson, 1993,1998)
Mechanisms To Learning Abstract Search
Control Knowledge
Hierarchical Goal Structure
Describes Problem Structure
Guides Problem Solving
Control Retrieval of Correct Rules
Initial Use of Weak Methods
Declarative Knowledge
Means-Ends Analysis
Learning by Analogy
Knowledge Compilation
Storage of successful problem solving episodes
Transformation from declarative to
procedural knowledge
Use Specificity
Geometry
Declarative Knowledge
Concepts, Axioms, Theorems, etc
Procedural Knowledge
Rules for Reason Giving Task
Rules for Doing Proofs
Little or no transfer
Others experiments
Transfer of both procedural and declarative knowledge
Tutoring: Humans and Computers
Learning Cognitive Skills in High School and College
Math, Physics, Programming, etc.
Lectures
Do problems in lab or homework
Problems
***Huge amounts of wasted time
(thrashing around)
***A majority of student do not complete
all of the homework
Delay of incomplete feedback
Serious problems with motivation
Not very effective method of instruction…
Human Tutors
Master same material in 1/4 the time!!!
Practical problems
Can we replace human tutors with computers?
The Anderson Tutoring Project at Carnegie Mellon U
Computer Based Problem Solving Environment Containing Tutor Where Student Does All Work By Entering Intermediate Results Into Computer
“Lecture” Material
Content and Timing
Skill level is determined by the number of homework problem you solve!!!!
Feedback is critical in enabling students to solve all training problems
Timing and Content
The Tutors Work (Better Performance in Less Time)
Why?
Students have to and can solve all training problems
Stop Thrashing
Feedback timing and content
“Lecture” Timing and Content
Anders Ericsson
Co-Author, Good Friend
Scholar!!!!
World’s Leading Authority on Exceptional Memory
A Major Player in the Study of Expertise
BUT
Anders insists on taking and defending some very strange positions
Talent play NO Role In The Development
of Expertise
High Levels of Expertise are Explained
by the Amount of Deliberate Practice
Expertise In Various Domains
Academic Domains
Science, Mathematics, Writing, Engineering, …
Music
Sports
Important Similarities in Expertise Across All Three
10 year rule
deliberate practice
role of teachers and coaches
Age varying age ranges of peak performance
The Role of “Talent”
The Standard Model of Expertise Circa 1990 (Holyoak, 1991)
Level of expertise is determined by amount of training, practice, and experience
10 years required to world-class expertise
Experts perform complex tasks in their domain much more accurately than do novices
Experts solve problems in their domain with greater ease than do novices
Experts have superior memory for information related to their domain
Expertise is highly domain specific
Experts are better at perceiving patterns among task related cues
Expertise can be explained by assuming that experts acquire a very large number of condition- action rules (10,000 to 50,000)
If So, then experts should be able to tell us their rules.
We should be able to directly teach novices these rules and make them “instant” experts.
THERE ARE IMPORTANT EXCEPTIONS TO ALL OF THESE CLAIMS!!!!!
Deliberate Practice and Instant Experts
Weak relationship between years of “experience” and level of performance or expertise
Tasks where experts are no better that novices
Stock market
Some types of clinical decision-making
Structure of the task environment
Deliberate Practice
Definition
In Music (Ericsson, et al.)
In Sports
Role of Teachers and Coaches
Expertise Is Determined by Amount Of Deliberate Practice
Instant Experts
Chick sexing
Tasks where expertise is mediated by a small number of rules that are very difficult to discover on your own.
• Experts Can be Slower Than Novices
• Writing and software design
• Asking novices to perform tasks usually done by experts
• Are novices and experts trying to perform the same task?
EXPERT AND EXCEPTIONAL PERFORMANCE:
Evidence of Maximal Adaptation to Task Constraints
Acquired anticipatory skills
circumvent general limits on reaction time
Distinctive memory skills
domain-specific expansion of working memory
capacity to support planning, reasoning, and
evaluation.
(Ericsson and Lehmann, 1996, p. 273)
Design, Scientific Research, Writing, …
Problem solving tasks that take days, weeks, …
Tasks that make extraordinary demands
on memory
Require massive amounts of background knowledge
Problem solving methods and representations
Schemata
Abstractions
Notations
Memory of solved problems and their solutions
Accurate episodic past experience
Case based reasoning
Require huge working memory
Very accurate record of last few hours of work
Limitations of notes and other forms of
external memory
Long Term Working Memory
Ericsson and Kintsch (1995)
Software Design (Jeffries, et al., 1981)
EXPERT PERCEPTUAL-MOTOR PERFORMANCE
Music, Sports, Typing, …
Anticipation, Anticipation, Anticipation…
Overlapping Preparation, and Execution
Control of Hands and Fingers
Hand-Eye Span in Typing and Sight Reading Music
Predicting Trajectory of Ball From Movements of Opponent
Baseball
Tenis
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