Originally Posted by Kavhan Isbul
I am not sure, but it seems whoever attacks gets an advantage. Numbers are of extreme importance - even if the enemy has barques, but he ahs one ship more, you are likely to lose. The final factor is the number of stars the fleet commander has, and yes, it is important and makes a huge difference. Also, if a fleet commander destroys a large fleet, he usually gets another star, and thus the more battles you win with a fleet, the more battles you are likely to win in the future with the same fleet and commander.
I cannot be 100% certain, but it seems to me that the outcome of naval battles depends on the outcome of land battles - if you win decisively on land, the AI will compensate by sinking your ships even if they are better and more than its own. The opposite is also true. Every time I win on land I tend to lose at sea, if the navies are somewhat close, and every time I lose a land battle I usually win at sea, often a single ship of mine with 0 star commander may sink 2 or 3 enemy ships.