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Flashcards in SPRING Problem Solving Deck (22):

describe the problem space (duncker 1945) / newell and simon 1972/ ratman 1965

problem arises when an organism has a goal but doesnt know how to achieve it
made up of many elements of a problem - analyse via search strategies
some easier than others to solve
n tile - limited state space - depends on o spaces available to move


what are the 3 elements of a problem

starting state of problem
goal - where want to be
set of processes- to reach the goal and transform from start to end state


well defined goal

not necessarily easier
know start and end and steps must complete


ill defined goal

more abstract
dont know how to get from a to b


adversary bd non adversary in problem space

wheterh or not someone is actively trying to stop you from reaching your end goal ie chess = adversary


knowledge rich vs knowledge learn in problem space

problems whose solution depends on specialized knowledge


Insight vs. non-insight in problem space

those solved "all of a sudden" vs. those solved more incrementally--in a step by step fashion.


what are the different types of search strategies in a problem space

depth first
breadth first
best first
AI researchers have suggested several forms, some (e.g., best-first search) not all of which are compatible with human cognition (e.g., they require too much memory or too-fast computation).


define depth first search strategy

with each move you plan the path to the goal
look ahead for the outcome of each move


define breadth first search strategy

interpret how alternative moves may influence


define best first search strategy

which moves allows you to be where you want to be the fastest


what are search strategies directed by

cost analysis
difference reduction
means end analysis


describe difference reduction

want to get from a to b as fast as possible
do so by reducing the space between the two
linear fashion
ie chicken not go around wire to get to food but stop


describe hill cimbing

difference reduction can be used in simple hill - climb to top
but require further insight to know that if want to go up a higher hill, you must first increase the distance before you can continue to resde (problem of local maxima)


describe the nine dot problem

people find difficult as make up own untold rules - cant go beyond pace of the dots
BUT requires further insight to recognise that can connect the dots by extrapolating from the dots - requires maximising what you get out of each move


describe the means end analysis (newell and simone 1972)

spects of both forward and backward reasoning in that both the condition and action portions of rules are considered when we decide which rules to apply -takes into account the gap between the current situation and the desired goal
ie IF (wm) goal to drive a car THEN(production memory) set subgoals to reach - recognises may need to deviate


describe newell and simon 1972 general problem solver computer simulation (GPS)

1. set goal/subgoal
2. diff between now and goal
3. operator - eliminate distance (ie may set another subgoal)
4. apply operator
5- 2-4 until main goal is achieved
- means in a process temporarily become an end goal


describe how the tower of hanoi might be completed in means end

goal to move bar 3 to from peg a to peg c
set subgoal to move bar 2 FROM bar 3
set subgoal to move bar 1 FROM bar 2 etc
- the more subgoals that must be considered the longer it takes to make an initial move


frontal lobe damage and means end

need memory resources to hold current goals - frontal love patients disproportionate difficulty with completing problems which requite multiple sub goals - problems in employing subgoals and holding in memory


describe the water jug problem luchins 1942

given 3 jugs and target to fill one up a certain amount - unlimited water
most are solved with one formula Y = B - A - 2C
BUT some have easier formula
1 - pps given one formula to solve and control given variety
- both then given solution y = a - c
pps with prev 1 fail and try to use prev while control readily apply new


what does the water jug problem (luchins 1942)

people have a tendency towards functional fixedness/einstellung
tendency to use their most well known method of problem solving even though it may not be the fastest or most efficient way


define einstellung

development of a mechanised stat/problem solving set
predisposition to solve problems in a speciifc manner even if there are more appropriate means