Originally posted by vulture
Yup, you're mistaken. The effect of 'rolling again' if you get a bad outcome is to increase the probabilities of all good outcomes. The ratio of probabilities of good outcomes remain the same, but they 'expand' to fill up the space taken by the bad outcomes (eg if 2 good outcomes have probilities of 50% and 25%, and the reroll probability if 25%, then the final probabilities for the good outcomes are 66.7% and 33.3%)
Yup, you're mistaken. The effect of 'rolling again' if you get a bad outcome is to increase the probabilities of all good outcomes. The ratio of probabilities of good outcomes remain the same, but they 'expand' to fill up the space taken by the bad outcomes (eg if 2 good outcomes have probilities of 50% and 25%, and the reroll probability if 25%, then the final probabilities for the good outcomes are 66.7% and 33.3%)
Let's make the numbers simple, let's say there are 100 possibilities for a roll, science has 40, settler has 10, barbs has 20, empty has 20 and map has 10 (I know there are more possibilties, but let's keep it simple).
In the case of expansionist, re reroll for barbs effectively redistributing the 20 by percentage over the remaining and get 50% science, 25% empty, 12.5% map and 12.5% settler.
Now if we ignore the barbs, we only have 80 possibilities on the rolls, which is to say 40/80 = 50% for science, 20/80 = 25% for empty, 10/80 = 12.5% for map and 10/80 = 12.5% for settler.
On the other hand, if the extra 20 taken out are moved to another possiblilty like empty, then you'd see 40% for science, 40% for empty, 10% for map and 10% for settler.
If the first case is the way it's calculated, then it is the same as expansionist, if it's the latter or a slight variant, then they are indeed different.
edit: I reread catt's original comment and think as thus: In all cases, the reroll happens if an outcome is deemed as unavailable (i.e. settler when you already have one). In this case, an expansionist civ vs. a non expasionist civ without a milirary unit will receive the same percentages for goody hut outcomes as both will get rerolls on the barb outcome.
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