Comp. Models of the Mind III Flashcards
Three model types:
- Performance models (Quantitative Modeling)
- Process/Task models (Qualitative Modeling)
- Competence models (Behavioral Outcome)
What is there to generally say about performance models?
- How knowledge/skills are employed in actual execution
- Statements and predictions about time, effort or likelihood of error when performing specific tasks
- focus on routine behavior in very limited applications
What is there to generally say about process/task models?
- The mechanisms by which the behavior of a system is produced
- The “how”, not the “what”, e.g. learning
What is there to generally say about competence models?
- What a given user knows and how this knowledge might be organized
- prediction of legal behavior sequences
- do not refer to actual execution
One example from 1954 of a performance model:
Fitts’ Law
For bullets about Fitts’ Law:
- information-theoretic account of simple movements
- robust model of human psychomotor behavior, based on execution time and distance
- prediction of rapid and aimed human movement
- movement time with a device (pen, mouse, …) as logarithmic function of distance and target size
Formula for Fitts’ Law:
MT = a + b log₂ (D/W)
Elements of Fitts’ Law’s Formula:
MT = a + b log₂ (D/W) MT = average time to complete movement a = device intercept (start/stop time) b = device slope (inherent speed) D = Distance from start point to centre of target W = Width of target along axis of motion/error tolerance (± W/2)
What is Meyer’s Law?
A refinement of Fitts’ Law for mouse movement.
In Fitts’ law the intercept and slope is determined through …
… straight-line regression analysis.
What does Fitts’ Law’s formula tell us about the performance rate?
Performance rate is constant over a wide range of D and W.
What is Hick’s Law about?
Selection time for a set of equally probable choices (e.g. choosing btw two buttons with the same function)
What can architecture refer to?
- a style and a method of design and construction (e.g. Byzantine architecture)
- orderly arrangements of parts, structure (e.g. architecture of a novel
- overall design or structure of a computer system
5 bullets to cognitive architecture:
- overall structure (ontology) and arrangment of the human cognitive system
- broad theory of human cognition, based on wide selection of human experimental data, and implemented as a running computer simulation program
- embodiment of a scientific hypothesis about those aspects of human cognition that are relatively constant over time and relatively independent of task (Ritter and Young, 2001)
- more detailed machanisms and processes for specific cognitive faculties
- related basic parameters (Sun, 2008)
What does a cognitive model consist of?
cognitive architecture + knowledge = cognitive model
About process/task models:
Running the model produces …
… behavior sequences that can be compared to those of humans
About process/task models:
Multiple models for any task, e.g. …
… different strategies
About process/task models:
QUANTITATIVE models produce not just specific sequences/coordination, but e.g. …
… execution times, error rates, learning curves
Cognitive architectures are large software systems which are …
… difficult to construct and maintain (done by whole teams, e.g. SOAR, ACT-R, etc)
General requirements and desiderata for computational models of the mind:
- integration of cognition, perception and action
- robust behavior in the face or errors, the unexpected and the unknown
- ability to run in real time
- ability to learn
- prediciton of human behavior and performance
- management (configuration, debugging, verification)
Who said the following about the GPS?
“It is often said … careful line must be drawn btw … machines … the same tasks that humans perform, and … machines … simulate the processes humans actually use to accomplish … tasks. …
GPS maximally confuses the two approaches - with mutual benefits.”
Newell & Simon, 1963
What does GPS stand for?
General Problem Solver
Define GPS!
An algorithm that searches for a successful solution to a problem, i.e.: a plan, given ANY well-specified search space
What is so cool about the GPS according to Gordon (2004)?
“One of the hallmarks of Articifial Intelligence planning systems is the general absence of representational commitments” (Gordon, 2004)
What does the GPS operate on and detect?
sentences and the differences btw sentences
The three subgoals of the GPS according to the means-end-analysis?
- transform object A into object B
- reduce difference btw object A and object B
- apply operator Q to object A
We have a GPS trace and a human protocol - what do we do?
We compare them!
What can we find out, when we compare GPS traces and think-aloud studies?
Two aspects in which the GPS cannot simulate subject’s behavior:
- distinguishing btw internal and external world
- adequate representation of the search space
also: sequential (GPS) vs. parallel (human)
What does the GPS reveal?
“that the free behavior of a reasonably intelligent human can be understood as the product of a finite and determinate set of laws.” (Newell and Simon, 1963)
Structure of production rules?
if … then condition-action pairs
