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Action, Complexity and Cognition
Matthias RauterbergIndustrial Design
Technical University Eindhoven
2003
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© M. Rauterberg, 20032/35
Possible Interpretations of 'Information'
1.) 'Information' as a message (syntax)
2.) 'Information' as the meaning of a message (semantic)
3.) 'Information' as the effect of a message (pragmatic)
4.) 'Information' as a process
5.) 'Information' as knowledge
6.) 'Information' as an entity of the world
Ref: Folberth, O. & Hackl, C. (1986, eds.) Der Informationsbegriff in Technik und Wissenschaft. München: Oldenbourg.
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© M. Rauterberg, 20033/35
“Information” for Learning Systems
before reception after reception Author
dof of the decision content of the decision HARTLEY 1928
uncertainty certainty SHANNON 1949 uncertainty information BRILLOUIN 1964 potential information actual information ZUCKER 1974 entropy amount of information TOPSØE 1974
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© M. Rauterberg, 20034/35
context human
mental model
situation-1
situation-2
com- plexity
positive incongruity
negative incongruity
Incongruity and Learning
Incongruity = Complexitycontext – Complexityhuman
learning
Ref: Rauterberg, M. (1995). About a framework for information and information processing of learning systems. In: E. Falkenberg, W. Hesse & A. Olive (eds.), Information System Concepts--Towards a consolidation of views (IFIP Working Group 8.1, pp. 54-69). London: Chapman&Hall.
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© M. Rauterberg, 20035/35
physical operation
feedback control of action
goal-, subgoal-setting
mental operation
task(s)
planning of execution selection of means
The Complete Action Cycle
synchronisation in time
synchronisation in space
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The Idea
Any human task solving process can be described in a finite state-transition chain, if the task can be described in an ‘action space’, specified by a finite set of states ( ) and transitions [ ].
State description: s0 : main menu s1 : modul "data" s2 : routine "browse" s3 : "wrong input" state
Action description: _ : ascii key "BLANK" a : ascii key "a" d : ascii key "d" h : ascii key "h" CR: carriage return F2: function key "2" F9: function key "9" TAB:tabulator key
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© M. Rauterberg, 20037/35
s0 d s1
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elementary processes Petri-Net
s0
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folding
The Folding Operation in Petri Nets
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Task Description
In the experiment all 12 users had to play the role of a camping place manager. This manager uses a database system with a data base consisting of three data files: PLACE, GROUP, and ADDRESS. All users had to solve the following four different tasks operating the database system:
Task 1: "How many data records are in the file ADDRESS, in the file PLACE, and in the file GROUP? Find out, please."
The user has to activate a specific menu option ("Datafile" in module "Info" of the menu interface) and to read the file size (solutions: PLACE = 17 data records, GROUP = 27 data records, ADDRESS = 280 data records).
Task 2: "Delete only the last data record of the file ADDRESS, the file PLACE, and the file GROUP (sorted by the attribute 'namekey')."
The user has to open (sorted according to the given attribute), select and delete the last data record (file: PLACE, GROUP, ADDRESS).
Task 3: "Search and select the data record with the namekey 'D..8000C O M' in the file ADDRESS, and show the content of all attributes of this data record on the screen. Correct this data record for the following attributes: State: Germany, Place number: 07. Remarks: Database system dealer can give a demonstration."
The user must select a certain data record (file: ADDRESS), update the data record with regard to the three attributes: State, Place number, Remarks.
Task 4: "Define a filter for the file PLACE with the following condition: all holidaymakers arrived on date 02/07/87. Apply this filter to the file PLACE, and show the content of all selected data records in the mask browsing mode on the screen."
The user must define a filter for the attribute "arrival date", apply the filter to the data file PLACE, and display the content of each data record found on the screen.
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System Description
The dialog system was the relational data base system ADIMENS version 2.21 with a character oriented user interface (CUI) running on standard IBM PC's with standard keyboard.
The whole dialog structure is strictly hierarchical organized with three levels:
(1) the main menu has 7 dialog operations (ordinary ASCII characters chosen from a menu) to go down to 7 different modules, and 5 function keys with specific semantics;
(2) at the module level each module has exactly 4 different dialog operations to change to routines and on average 4.1 (±1.7; range: 0-5) function keys with specific semantics;
(3) at the routine level the user has only on average 3.7 (±2.9; range: 0-10) different function keys to control the dialog (additionally all ASCII keys and the 4 cursor keys are usable).
The number of all ordinary dialog contexts (main menu, modules, routines) is 1+7*4=29.
But to describe the complete dialog structure with all help, error and additional dialog states we need at least 144 different system states.
To change from one state to the other the system offers overall 358 different dialog operations (transitions).
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physical execution
evaluation and control
goal-, subgoal setting
mental execution
task description
action planning selection of means
goal
system state
selected action
result
Observable Data
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G_2
Start menu
M_3
Main menu Main menu. F file
F_3
User key press
1
User key press
Main menu
i
User key press
Info
Info.file Info.screen1 Info.screen2
d
M_22 M_22 M_22
DB content display
User key press
Info.screen3 Info
Info.screen1 stopped
Info Main menu Start menu Start menu Start menu
M_11 d
Automatic transition
User key press
M_22 M_22 M_22 M_11 d
User key press
M_22 BL F_10 M_22 M_22
M_11 h h
User key press
User key press
G_2 F_10
User key press
... continues
... continues
... continues
... continues
Automatic transition
Automatic transition
Automatic transition
Automatic transition
Automatic transition
Main menu
marked
Info.file Info.screen1 Info.screen2 Info.screen3 Info
Info.screen1Info.file
Info.screen3
Info.screen2Info.screen1
DB content display
DB content display
DB content display
DB content display
DB content display
User key press
User key press
DB content display
DB content display
DB content display
Example of a task solving process
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s0
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structure as a
Petri net
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FOLDING
observable process
unknown structure (e.g., mental model)
?
main menu level
module level
routine level
How to Extract the User’s Mental Model?
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How to measure complexity? In Computer Science... • algorithmic information (Solomonoff-Kolmogorov-Chaitin) • computational universality • computational time/space • according McCabe in graph theory In Physics... • thermodynamics potentials • long-range order • long-range mutual information • self-similar structures • thermodynamic depth • logical depth In Psychology... • properties of objects (e.g. valence) • properties of attributes (e.g. ordinality) • properties of cognitive structure (e.g. centrality)
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Net Complexity Metrics
McCabe (1976):
Kornwachs (1987):
Stevens, Myers and Constantine (1974):
[with P=1]
Validation study:
Ccycle from McCabe outperforms all other metrics!
state-1
state-2
transition-2transition-1
Simple Petri Net:
Ref: Rauterberg, M. (1992). A method of a quantitative measurement of cognitive complexity. In: G. van der Veer, M. Tauber, S. Bagnara & M. Antalovits (eds.), Human-Computer Interaction: Tasks and Organisation--ECCE'92 (pp. 295-307). Roma: CUD.
T = number of transitionsS = number of states
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state transition net
interactive dialog system
automatic recorded process
system description
adjacency matrixfrequency matrix
the analyzing program AMME
ascii text outputfile with
quantitative measures
graphic outputfile in PostScript
format
0 1 2 3 0 0 1 0 0 1 3 0 1 0 2 0 0 0 1 3 0 2 0 7
0 1 2 3 0 0 1 0 0 1 1 0 1 0 2 0 0 0 1 3 0 1 0 1
• simulation • task-subtask
• similarity • learning • MDS
• distances • personal styles • MDS
• complexity • routine
• interface design • deadlocks
USER
"defaultp.ps"
Petri net simulator PACE
"*.str""*.log"
Path finder KNOT
Markov analyzer SEQUENZ
transformation to a syntactical correct logfile
v2132 13 S'initial_state' 15@-12
390@330 S 0 0 Tnil nil 480@420
S 1 2 nil 0 cS CSCS cSsS SSRS rS 5 tftt 10 ft
"*.net" "*.ptf" "*.mkv" "*.pro""*.ps"
any Postscript interpreter
any text processor
The AMME Program Structure
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BCcycle = T – S + 1
BCcycle
Box Plot Box Plot
1 20
10
20
30
40
*
*
*
beginners - experts1 2 3 4
0
10
20
30
40
*
*
task no.
SOURCE SUM-OF-SQUARES DF MEAN-SQUARE F-RATIO P
experience 275.521 1 275.521 10.337 0.003
tasks 259.563 3 86.521 3.246 0.032
exp. x tasks 25.729 3 8.576 0.322 0.810
ERROR 1066.167 40 26.654
Behavioral Complexity (BC) àla McCabe (1976)
Experiment:
N=6 novices; N=6 experts4 tasks with a databaseMetric BC=Ccycle
Ref: Rauterberg, M. (1993). AMME: an Automatic Mental Model Evaluation to analyze user behaviour traced in a finite, discrete state space. Ergonomics, vol. 36(11), pp. 1369-1380.
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Validation of the functional equivalence, computed by the similarity ratio (SR)
Adding goal setting structure
Reconstructed mental task modelHuman mental model
?
Observation of human behaviour
Folding
Adding sequential and temporal information Model
execution
original behavioural sequence simulated behavioural sequence
Device model
2
G_2
Start menu
M_3
Main menu
F_3
User key press
Automatic transition
Automatic transition
MsDOS
G_2
Main menu
F_3
Start menu
M_3
Automatic transition
Automatic transition
User key press
MsDOS
Main menu Main menu
F-fileStart menu
F_10 M_3 h F_3 1 i hG_2
MsDOS
Main menu Main menu F-file
Start menu
F_10 M_3 h F_3 1 i hG_2
MsDOS
1
3
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i
Validation of extracted Mental Models
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SR 1 org ,tR sim, tR max orgR
sim1N
orgN
t1
simN
org
2N
* 100%
The Similarity Ratio SR
Legend: R is the absolute rank position in the original or simulated process
Ref: Rauterberg, M. (1995). From novice to expert decision behaviour: a qualitative modelling approach with Petri nets. In: Y. Anzai, K. Ogawa & H. Mori (eds.), Symbiosis of Human and Artifact: Human and Social Aspects of Human-Computer Interaction--HCI'95 (Advances in Human Factors/Ergonomics, Vol. 20B, pp. 449-454). Amsterdam: Elsevier.
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d
a
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space
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d
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40% 77% 76% 10% 10% 10%67%79% 10% 83%
Simulated logfiles with Model-1
43%
d
h
10%
Simulation Results: Model-1
SR
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d
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94% 94% 96% 96% 94% 94%94%96% 94% 94% 94% 96%
Simulated logfiles with Model-4
95%
Simulation Results: Model-4
SR
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Model-2 (first part): Event-driven goal setting strategy
Main menuMain menu
F-fileStart menu
F_10 M_3 h F_3 1 i hG_2
MsDOS
Syste
m le
vel
Co
gn
itive le
vel
Go
al
insta
ncia
tion
le
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Actio
n le
vel
task description
observable action
goal instanciation
goal selection
Model-2: event-driven goal setting
Ref: Rauterberg, M., Fjeld, M. & Schluep S. (1997). Parallel or event-driven goal setting mechanism in Petri net based models of expert decision behaviour. In: S. Bagnara, E. Hollnagel, M. Mariani & L. Norros (eds.), Time and Space in Process Control--CSAPC'97 (Sixth European Conference on Cognitive Science Approaches to Process Control, pp. 98-102). Roma: CNR.
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Model-3: parallel goal setting without feedbackS
ystem
leve
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oa
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Model-3 (first part): Parallel goal setting strategy
M_3 h F_3 1 i hG_2F_10
Main menuMain menu
F-fileStart menuMsDOS
cognitive processtask
description
goal instanciation
observable action
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Go
al
insta
ncia
tion
le
vel
Actio
n le
vel
M_3 h F_3 1 i hG_2F_10
Main menuMain menu
F-fileStart menuMsDOS
Syste
m le
vel
Co
gn
itive le
vel
Fe
ed
ba
ck le
vel
Model-4 (first part): Parallel goal setting with feedback
task description
feedback
cognitive process
observable action
goal instanciation
Model-4: parallel goal setting with feedback
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SR 1 org ,tR sim, tR max orgR
sim1N
orgN
t1
simN
org
2N
* 100%
Table 1: The model complexity (Ccycle) and similarity ratio (SR) of the modelingapproaches-1, -2, -3 and -4 [std:=standard deviation].
modelingapproachno. 1
modeling approachno. 2
modelingapproachno. 3
modeling approachno. 4
Ccycle: (mean ± std): 13 ± 5 43 ± 17 57 ± 25 101 ± 43
Ccycle: (min…max.): 6…18 22…68 30…97 55…170
SR (mean % ± std): 41 ± 28 66 ± 21 88 ± 11 100 ± 0
SR (min…max. %): 3…79 36…98 67…100 100…100
# simulated sequences 5*6=30 5*6=30 5*6=30 5*6=30
The Similarity Ratio SR
Legend: R is the absolute rank position in the original or simulated process
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#MTT = #TST / #DS
Measuring 'Personality Styles'
#R = #AT / #DT
Measuring 'Routinization'
Ccycle = #T – #S+P with #S =< #T and P=1
C'cycle = #F–(#T + #S)+P with #S > #T and P=1
Measuring Complexity
Overview over different measures
T = number of transitionsS = number of states
F = number of connectors
TST = task solving time
AT = all used transitions
DT = all different transitions
DS = all different states
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The common AI assumption
observable behaviour
mental model
learning
Ref: Rauterberg, M. (1996). About faults, errors, and other dangerous things. In: C. Ntuen & E. Park (eds.), Human Interaction with Complex Systems: Conceptual Principles and Design Practice (pp. 291-305). Norwell: Kluwer.
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complex system
operator
beginner
advanced
expert
learning time
interaction
SC BC CC
We found a negative correlation between Behavior-Complexity BC and [assumed] Cognitive-Complexity CC
Experiment:
N=6 novices; N=6 experts4 tasks with a databaseMetric BC=Ccycle
The reality: what we found!
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observable behaviour
mental model
The reality: how to interpret?
learning
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Mental Knowledge Structures: a Metaphor
s0
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s2 s3F3
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"wall“: knowledge about unsuccessful behavior
"dales“: knowledge about successful behavior
This conclusion would have major impact e.g. on training procedures of operators of complex systems!
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Learning: the traditional understanding
Before learning phase After learning phase
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Mental decision making for concrete actions is like rolling a ball between hills
Decision and Action: a new View
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Learning and experience
task complexity
time-1 time-2 time-3
time
task-1 task-1' task-1''
Ref: Rauterberg, M. & Aeppli, R. (1995). Learning in man-machine systems: the measurement of behavioural and cognitive complexity. In: Proceedings of IEEE International Conference on Systems, Man and Cybernetics--SMC'95 (Vol. 5, IEEE Catalog Number 95CH3576-7, pp. 4685-4690). Piscataway: Institute of Electrical and Electronics Engineers.
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2
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task 1
week-3week-2week-1
task 1' task 1 task 1' task 1 task 1'21
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task 1
week-3week-2week-1
task 1' task 1 task 1' task 1 task 1'
The Learning Experiment
Time structure and knowledge structure are different!
Task solving time Behavioral complexity
N=6 men (average age of 25 ± 3 years)
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© M. Rauterberg, 200334/35
Conclusions
• A valid metric for task complexity based on task structure allows an objective comparison
• Automatic analysis for unconstrained task solving behavior allows analysis with applied statistics
• A new analysis and modeling approach leads to new insights…
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© M. Rauterberg, 200335/35
Thank you for your attention.