KillerPoodle wrote:
So, for example that could give values for a and b as follows:
1.0 and 1.869 or 0.8 and 1.49 (e.g. a 20% penalty to cav atk and a 50% bonus to bow defence) or 0.6 and 1.12 etc...
There are an infinite number of possible values from this one equation  we would need more results to start narrowing down the actual values.

for me the only way to know the %age is first of all to find a square on which one an unit is not affected... so +0% bonus on attack or defense : so we could have the (Power)*1.0 and find the %age value of the other units on this square.
i think about plains and swordmen, its easy to know the bonus of every units on it because swordmen are unaffected:
Hills also
benefit ranged units and spearmen to a lesser extent, and still
penalise cavalry, but also to a lesser extent. Swordsmen are largely
unaffected by hilly terrain.
Plains provide
the opportunity for cavalry to shine  their ability to maneuver makes
them the masters of open flat space. Lightly armoured spearmen dislike
the open terrain of plains, where they are easier targets for cavalry
and archers.
Edit: swordmen largely unaffected on hill (they are affected on mountains). they dont talk about them on plains. we can strongly suppose that swordmen are totally unaffected on plains
It will be much difficult on hills, forests, and mountains because we dont have any reference: every unit seems to be affected by the type of these grounds
Exemple on plains with the previous report (swordmen attack spearmen):
they both have a power of 1000 (for exemple)
a=%bonus on swordmen attck
b=%bonus on spearmen def
397= 32
32/39= 0.821
1000*b/1000*a=0.821
b/a=0.821
swordmen unaffected => a=1.0
b=0.821a
b=0.821 => 17.9% penalty on spearmen def
(but because of the weight of the army, the luck etc... its better to say a penalty between 15% and 20%)
Edited by Mandarins31  29 Aug 2010 at 04:20