There are two XP bonuses. One is an XP bonus that goes to newly trained troops and is present with the second tier of specialists. The other is a per turn +10 XP for units which idle (or end turn) on the correct barracks type.
The defensive bonus is for units standing on the tile.
edit: as far as I know the only way to improve the actual city tile defense is the wall->moat->tower line of buildings.
Ah, right, that makes sense. But for the sake of argument, say that I’m playing with events turned off. Is everything I need to know about the likelihood of war visible in the opinion breakdown, or are there other unseen factors at work?
To add to what @davehemke replied, when you have a unit selected, relevant improvements will be highlighted in green. So if you select a military unit, a site like a shrine, barracks, or harbor that adds xp will light up in green. Very helpful interface assist!
There must surely be a consideration of relative military strength in the equation, and whether the AI is already in another war. Possibly how much tribute would stop being sent to them.
Perhaps also whether I’m in a defensive pact thingy (can’t remember the name) with another nation, and how strong they are. I’m not sure about that as the last time I had one I kept being declared on anyway (but that might have been event-driven).
But the original implied question was whether a sufficient positive opinion could preclude a war declaration. I don’t know the answer to this, but I do know the answer for Civ IV, which might well turn out to be the same. In that game, the AI (different for each leader) has a relation level (i.e. cautious, pleased, friendly) limit above which it will never start to prepare for war against you. If it starts preparing for war and then the relation level pushes over the limit, it will still finish the preparations and attack. It can abort a planned attack if other circumstances change though (such as relative strength).
No, the overall result of that calculation isn’t visible anywhere, and that’s by design I believe, not a case of missing info. There’s also a few special rules like the AI won’t declare war too early (turn limit based on difficulty), won’t declare if you just completed a trade deal, and a few such special cases.
Overall, the war roll is part of the AI diplomacy routine, which begins at turn 10, and runs every other turn per AI, with a 50% chance. To make that more clear, each AI nation will only run the diplomacy checks every other turn (so if playing against 4 AIs, two will run on a given on a turn), and only if a 50% roll passes first. So a specific AI nation will run its diplomacy, on average, every 4 turns.
Good to know! And note that I’m not at all looking at this as missing info! I’m totally down with some uncertainty in diplomacy, with something that makes it more than just a deterministic system, like mining ore or developing culture. I just wanted to verify that it was in there.
You could also look at placing governors who have good research bonuses and choosing new advisors who give you more research. Whatever you do, doing it immediately is the right choice to have a chance.
Q: Is there any penalty for a negative training income?
When you’re running a shortage of raw materials like wood or stone, you’re dinged for the cost of the shortage. And I believe when you’re running a negative money income, you automatically sell resources to make up the deficit. But what happens when you’re running a deficit on something that can’t be bought with money?
I’ve got a game going where I’ve got more training going out that coming in. What little I’m producing is being sent out in trade and tribute, but I don’t even have enough to meet that demand. So I’m pegged at zero training, with a negative income of -50. It’s been this way for a couple of turn, but my trade and tribute deals are still in effect, even though I can’t pay them. And I’m not able to find any negative effect from this.
Can I just run a negative value without any side effects (other than being unable to do anything that requires spending training)? It seems like the trade and tribute deals should be canceled, but as far as I can tell, they’re going strong.