by StevenJoyce on Sat Nov 21, 2009 2:39 pm
I've been thinking about when its worthwhile to delay turning in spoils in a flat-rate game, and I'd appreciate comments by more experienced players. I'm thinking that, aside from a few exceptions, you should cash a set of spoils whenever you have that option.
Scenario #1: You have 3 red spoils cards and 1 green spoils card at the beginning of your turn. You could turn the red cards in for 4 troops, or you could wait a turn. If you get a blue spoils card (1/3 probability, assuming you can get a card), you will turn in a mixed set of spoils for 10 troops. If you get a red or green spoils card (2/3 probability), you get 4 troops. Thus, at the cost of a one turn delay, you increase your expected number of troops by (1/3)*(10-4)+(2/3)*(4-4) = 2.0. Now sometimes you don't have very many productive options for using extra troops on the current turn, and the gamble would be worth it. Other times, the strategic situation may be ambiguous, and a one turn delay would help clarify where the extra troops should be placed. But usually there's some pressing need (surviving another turn, eliminating an opponent, busting an opponent's bonus, securing your own bonus, or even simply being able to safely get another spoils card) that makes a one-turn delay significantly more costly than giving up the opportunity for an average of 2.0 troops.
In all other scenarios, the benefit from delay is even less.
Scenario #2: 3 green cards, 1 red card (or blue card). 6 troops immediately, versus a 1/3 chance at a one-turn delayed 10 troops, for an expected gain from delay of (1/3)*(10-6)+(2/3)*(6-6) = 1.33.
Scenario #3: 3 blue cards, 1 red card (or green card). 8 troops immediately, versus a 1/3 chance at a one-turn delayed 10 troops, for an expected gain from delay of (1/3)*(10-8)+(2/3)*(8-8) = 0.67.
Scenario #4: 3 red cards. 4 troops immediately, versus a 2/9 chance at a two-turn delayed 10 troops, for an expected gain from delay of (2/9)*(10-4)+(7/9)*(4-4) = 1.33.
Scenario #5: 3 green cards. 6 troops immediately, versus a 2/9 chance at a two-turn delayed 10 troops, for an expected gain from delay of (2/9)*(10-6)+(7/9)*(6-6) = 0.89.
Scenario #6: 3 blue cards. 8 troops immediately, versus a 2/9 chance at a two-turn delayed 10 troops, for an expected gain from delay of (2/9)*(10-8)+(7/9)*(8-8) = 0.44.
Does this analysis seem reasonable, or am I overlooking something?