Lecture 6 Flashcards
What is a problem?
A situation where a living organism has a goal but does not know how this goal is to be reached.
Problems are created because…
There is a goal
There is a need to think about how to achieve the goal
There is a lack of relevant knowledge to immediately solve the problem
What are the 4 different types of problem
Well defined problem
Ill defined problem
Knowledge rich
Knowledge lean
Well defined problem
All aspects of the problem are specified
assembling furniture
Ill defined problem
Some aspects of the problem are unspecified (assemble furniture without instructions)
Knowledge rick problem
Specific prior knowledge is required (crossword)
Knowledge lean problem
Little prior knowledge is required (sudoku)
What is reproductive thinking
re-using old experiences to solve a problem
e.g. trial and error learning
What is productive thinking
Coming up with new responses or strategies for solving a problem
Behaviourists Vs Gestaltists
Behaviourists: all problem solving is reproductive (trial and error)
Gestaltist: some problems can be solved by insight, the problem is restructured so the solution becomes clear
Kohler & Birch
Kohler
Sultan the ape
Has to get banana from outside his cage
Provided with two sticks that can be joined
Birch
Apes raised in captivity
Sultan had trial and error learning in the wild
Insight in Humans - Maier
Problem - how can I tie two strings together.
There were four solutions but Maier was looking for one particular solution
Gestaltists claim that this problem is difficult to solve in a trial and error fashion. Participants must restructure the problem until the solution presents itself.
Does experience of problems help with problem solving?
If problem solving is just trial and error then more experience should lead to better/faster solutions
Duncker- candle problem
matches, 3 small boxes full of tacks and 3 candles.
Fix candle to door frame so it burns in a stable fashion
Functional fixity
Failure to perceive new uses for old objects
Participants who fail to solve problems often dont remember the boxes
Luchins 1912 Water Jar Study
Studied effect of experience on problem solving
Controlled the past experience:
half were trained on complex 3 jar problems
the rest were given no training
New problem with 2 jar solution:
95% of no training group used 2 jars
64% of the trained group failed to solve the problem
Einstellung
Mental set - a strategy used to solve a problem even when it is inappropriate or inefficient
Evaluation of Gestalt approach
+ introduced and investigated insight as a method of solving problems
+emphasised restructuring and representational change- very influential concept
+ showed that experience does not always help problem solving
- focus on knowledge lean, well specified problems
- Insight and restructuring was vague. Describes what happens during problem solving but not how it happens
Representational change theory
Attempt to integrate gestalt insight theory with information processing approach
Structure of problem determines what related knowledge can be retrieved from LTM
Changing the structure of the problem means different knowledge can be retrieved from LTM, may allow person to solve problem.
Changing representation
Three main ways to change representation of problems:
elaboration: adding more information about the problem
contraint relaxation: changing how some aspect of the problem is interpreted
Re-encoding: changing how some aspect of the problem is interpreted
Evidence of changing representation
Move one stick to make an equation correct
change values or operators
solvers would fixate on the operators but non-solvers did not
Evaluation of changing representation
+restructuring does appear to help with many insight problems
+mechanisms of problem solving are better specified
- does not predict which types of restructuring will help problem solving
- no account for individual differences
- may be specific to certain types of problem
Computational approach
Newell and Simon
Developed a computer simulation of problem solving. Designed to solve well defined problems.
Assumptions of general problem solver:
information processing is serial
we have limited short term memory capacity
relevant information can be retrieved from LTM
Problem space
GPS based on human problem solving.
Problem space- representation of a problem
Initial state, goal state, all possible moves or operations to change the state of the problem, all possible problem states between the initial state and the goal state
Problem solving- changing the initial state to the goal state through a series on intermediate states
Nerwell and Simon identified 2 important heuristics
- Mean end analysis
Identify difference between current state and goal
form a sub-goal that reduces this difference
Perform operation that will attain sub-goal
e.g. following instructions to assemble IKEA furniture by making sub-components - Hill-climbing
change current state to a state that more closely resembles the goal
used if you dont really know how to solve the problem
E.g. assembling IKEA furniture without instructions
Evaluation of Newell and Simon
+works well with well defined, knowledge poor problems
Experimental evidence suggests we do use heuristics
-general problem solver may not always operate in the same way. Better at remembering previous states. Worse at planning future moves.
Only works with well defined problems, most human problems are ill defined.
Cannot account for insight
Cannot account for individual differences
