239Re: what is admissible??
- Oct 20, 2003Admissible Heuristic:
#Def : A heuristic function (h(n)) with restriction that never
overestimates the path cost ('n'-->'G').
where 'n'= any node/state along the path,
& 'G'= desired Goal state/locaton.
#Ex : h SLD (n) = Straight-line distance between n & goal.
(in the route-finding problem.)
#This is a monotonic increasing function since it follows
the Triangle inequality
(sum of any two sides of a triangle > the third side)
(QED by Pearl in 1984 )
#its a function of any kind, not an algorithm
--- In email@example.com, "fakarim_nsu" <fakarim_nsu@y...>
> Hi there,is
> "admissible" heuristic can be any function.But provided that it
> cannot overestimate the cost to reach the goal!for example in the 8
> puzzle problem in the text, a rule of thumb can be it may need 20
> moves to reach the desired goal. Now if ur heuristic takes the
> misarranged tiles as a function or the "manhattan distance" which
> the distance for a tile from its actual position both of them canbe
> considered as "admissible heuristic" because none of them exceedsalgorithem?
> the 20 moves(the example in the book shows they need 7 and 14 steps
> respectively i guess).Thanx
> --- In firstname.lastname@example.org, "hkstudentinuk"
> <hkstudentinuk@y...> wrote:
> > Hi there everyone
> > I am new to AI, just starting a new couse.
> > what is the definition of admissible?? is admissible an
> > is the definition of it "never overestimates the cost to reachthe
> > goal"?
> > what does admissible means in english in this context?
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