[Freeciv-Dev] Re: Want calculation (Was:Re: flying AI (PR#1162))

[Raahul Kumar <raahul_da_man@xxxxxxxxx>]

--- Gregory Berkolaiko <gberkolaiko@xxxxxxxxxxx> wrote:
>  --- "Ross W. Wetmore" <rwetmore@xxxxxxxxxxxx> wrote: 
> > 
> > This is used for veteran units. Obviously they are 40 somethings better
> > than the standard unit build_cost, probably because rifleman are the
> > prototypical unit and this is double the shield cost or something :-).
> 
> I thought it is used as the boat cost if we need the boat.
> 
> > To repeat a former caution though. There is a rationale for everything
> > if you can hold onto your sanity long enough to figure it out. But
> > these
> > long involved calculations are not in themselves particularly important
> > or useful. They attempt to mimic some human assessment process, but
> > don't
> > really cover the full spectrum, so accuracy is meaningless within a
> > fairly broad range.
> 
> I disagree on "mimic some human assessment" issue.  It's an attempt to
> code mathematically sound tactics IMHO.  Which is "to profit whatever we
> do".  The human assessment is more "can I kill it somehow?" while the
> code attempts at "will I profit if I try to kill it?" approach.
> 
> Possibly bigger difference is in general view on combat:
> Human "here is the enemy, where is my Howitzer?" 
> and AI "here is my howitzer, where is the enemy?"
> 
> But it is general philosophy and here is something concrete:
> I managed to hold on to my sanity for long enough to at least partially
> decode "want" calculation.  I was looking at the lines around
> http://www.freeciv.org/lxr/source/ai/aiunit.c?v=cvs#L1411
> (function find_something_to_kill)
> 
> Want = Operation_Profit * Amortization_Factor
> 
> where 
> 
> * Amortization_Factor is completely beyond me (but it's a function of the
> estimated time length of the operation).
> 
> * Operation_Profit = Battle_Profit - Maintenance
> 
> where
> 
> * Maintenance 
>   = (1 shield + Unhappiness_Compensation) * Operation_Time 
>   (here unhappiness is from military unit being away from home)  
> 
> * Battle_Profit
>   = Shields_Lost_By_Enemy * Probability_To_Win 
>     - Shields_Lost_By_Us * Probability_To_Lose
> 
> That is Battle_Profit is probabilistic average.
> 
> In the calculation the probabilities enter approximately (and the
> approximation is rather bad, but who cares).
> 
> Best,
> G.
> 

I'm stealing this wholesale for the primer on the want equation I'm sending
in. I've got some ideas on amortise, although I hardly understand it yet.
Should
I include that in the update to README.AI?



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