Problem

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COGNITIVE 2012
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Types of problems
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Theories
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Gestalt
Representational Change Theory
Progress Monitoring Theory
Transfer of Training
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It is the evening before an exam, the text book you need is
unavailable in the library.
There is not one obvious solution
You have upgraded your computer from Windows 2000 to
Windows Vista and want to perform certain operations as
before
Learning (helpful and harmful)
You wish to avoid stale-mate in chess
Expertise
You wish to become a better footballer
Is it clear when the objective has been achieved
Defining problem-solving activity:
1)
2)
3)
It is purposeful, goal directed action
It does not involve automatic processes, but relies
on cognitive processes
It is only a ‘problem’ if the solution is not available
immediately.
‘h i j k l m n o’
Well defined problem: All aspects of the problem are
clearly laid out. We know the initial state, the rules,
and the goal state.
e.g. a maze
ILL defined problem: None of these things are as clear.
“It is the evening before an exam, the text book you need is
unavailable in the library and the bookshop is closed”
Starting point? Potential solutions? End point?
Gestalt Psychology: A theory of mind that emerged
from Germany in the early 20th century
Concerned with entities/experience as a whole rather
than consisting of parts
They drew a distinction between
reproductive thinking, involving re-use of previous
experience, and
productive thinking involving a novel restructuring of the
problem
Insight occurs during productive thinking when the problem is
suddenly restructured and the solution becomes clear.
Kohler (1925) observed insight with apes
Novick & Sherman (2003) highlighted the difference between
subjective experience and the underlying process
In a series of experiments, expert and non-expert anagram
solvers were presented with a series of anagrams.
Evidence that insight is unique: Novick & Sherman found that
when rating the experience of solving anagrams both
groups often reported ‘pop out’ solutions. ‘The solution
came suddenly, seemingly out of nowhere’
Evidence that insight does not work like this: In a different
experiment participants had to indicate after brief exposure
(469ms) if the word was an anagram or not.
Both groups performed better than chance
Representational change theory is an attempt to incorporate
some Gestalt ideas into a working theory (Ohlsson, 1992)
It is based on the following assumptions:
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A problem is represented in a certain way in the person’s
mind and this serves as a probe for information from longterm memory
The retrieval process spreads activation over ‘relevant’ long
term memory items
Representational change theory is an attempt to incorporate
some Gestalt ideas into a working theory (Ohlsson, 1992).
It is based on the following assumptions:
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A block occurs if the way a problem is represented does not
lead to a helpful memory search
The way the problem is represented changes and the
memory search is extended, making new information
available
Representational change theory is an attempt to incorporate
some Gestalt ideas into a working theory (Ohlsson, 1992).
It is based on the following assumptions:
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Representational change can occur due to ‘elaboration’
(addition of new information) ‘constraint relaxation’ (rules
are reinterpreted) or ‘re-encoding’ (functional fixedness is
removed)
Insight occurs when a block is broken and retrieved
knowledge results in solution
Example: Can the 62 squares on this mutilated draught-board
be covered with 31 dominoes
Mutilated draught-board:
Kaplan & Simon (1990) had participants think aloud as they
tried to solve this problem
All started by mentally covering the squares with dominoes
(758,148 possibilities!)
Those who solved the problem reported a ‘representational
change’ such as this…
Mutilated draught-board:
If each domino is represented as an object covering one black
and one red square (re-encoding)
And represent the draught-board as having lost 2 black squares
(elaboration)
It becomes clear that no arrangement will allow 31 dominoes to
cover the 62 spaces
Draw four straight lines to join all the dots without taking the
pen off the page
This problem was given to employees at Disney as is reportedly
the origin of the expression ‘thinking outside the box’
Participants who did not solve the 9 dot problem usually failed
to consider extending the lines beyond the grid
Constraint relaxation mentioned earlier allows someone to
consider the correct solution
Knoblich et al. (1999) showed the importance of constraints in
reducing the likelihood of insight
Problem: Reposition one match to make this equation correct
Knoblich et al. (1999) showed the importance of constraints in
reducing the likelihood of insight
Problem: Reposition one match to make this equation correct
Our experience of equations often involves changing numerical
values as in
But not changing operators (+, -, =)
Insight is more difficult in the second example because reencoding operators is more advanced than re-encoding
numerical values.
Knoblich et al also included eyetracking data which showed a
great deal of attention was paid to the numerical symbols
but not the operators.
‘Thinking outside the box’ allows us to see the operators as
changeable also
MacGregor et al (2001) have put forward this theory. There are
two main features
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Maximisation heuristic: Each move or decision is an
attempt to make as much headway as possible towards the
goal
Progress monitoring: The rate of progress is assessed
constantly, and if it is deemed to be slow and inefficient
criterion failure occurs. An alternative strategy is then
sought.
MacGregor et al (2001) have put forward this theory. There are
two main features
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Maximisation heuristic: Each move or decision is an
attempt to make as much headway as possible towards the
goal
Progress monitoring: The rate of progress is assessed
constantly, and if it is deemed to be slow and inefficient
criterion failure occurs. An alternative strategy is then
sought.
MacGregor et al. version of nine dot problem
A
MacGregor et al. version of nine dot problem
B
If ‘constraint relaxation’ is all that is required to think outside
the box, then participants should do better on A than B
If criterion failure is necessary then participants will do better on
B, because they can cover fewer dots in the next two
moves, and so will realise they are on the wrong path
sooner.
MacGregor et al. found that only 31% of those given A were
successful. Compared to 53% of those given B.
If ‘constraint relaxation’ is all that is required to think outside
the box, then participants should do better on A than B
If criterion failure is necessary then participants will do better on
B, because they can cover fewer dots in the next two
moves, and so will realise they are on the wrong path
sooner.
MacGregor et al. found that only 31% of those given A were
successful. Compared to 53% of those given B.
Ormerod et al. (2002) 8 coin problem.
Moving only 2 coins, leave each coin touching 3 others
Ormerod et al. (2002) 8 coin problem.
Moving only 2 coins, leave each coin touching 3 others
Ormerod et al. (2002) 8 coin problem.
Moving only 2 coins, leave each coin touching 3 others
Ormerod et al. (2002) 8 coin problem.
If the strategy employed simply seeks to achieve a short term
goal of bringing one particular coin to rest in contact with 3
others, then there is ‘no move available’ in the first
condition, but 20 moves available in the second
92% solved the problem in the first condition, 67% in the
second
Again, strong evidence for the importance of ‘criterion failure’
Evaluation:
The central claim being that insight is most likely to occur when
constraint relaxation is combined with criterion failure.
There is good evidence for this
Deals well with the motivation for changing strategy
Refers to how our experience of past problems influences our
ability to solve new ones.
Not surprisingly there can be positive and negative transfer
E.g of negative transfer: Luchins (1942) water jar problems
Jars:28L
Aim: 25L
76L
3L
Participants who had trained on a number of difficult 3 jar
solutions requiring the same complicated process failed to
see the simplicity of the solution here
Other factors to be considered
Far transfer: Refers to transfer to a dissimilar context
E.g. Learning about experimental method in science class
(control groups, confounding variables etc.) and using the
same principles in real world settings (deciding how to
make the nicest biscuits)
Near transfer: Transfer to a similar context
E.g. Learning Luchins’ water jar solutions
Lab studies often limited to near transfer
Eysenck & Keane, Chapter 13
Sternberg, Chapter 11
Article: Ormerod, T. MacGregor, J. Chronicle, E. (2002) Dynamics
and Constraints in Insight Problem Solving. Journal of
Experimental Psychology: Learning, Memory, and Cognition
vol. 28 (4) pp 791-799
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