Saturday, January 11, 2020

Euchre bots update

The site was down for about 10 minutes this morning for some maintenance.

An update has been applied that tweaks the Euchre bots' tactics. I have a couple of pages that explain what was done.

First, the Euchre bots will now always lead trump if they are left of dealer and their 3rd seat partner declared trump. That page has some stats which indicate it is a successful tactic.

Second, the Euchre bots now have an improved algorithm for calling the up card when they are the dealer. If calling up will result in them having 3 trump cards, they will always call up. For example, if the up card is the 9 of clubs, and they have the 10 of clubs and the jack of spades, they will order the up card into their hand. That would give them 3 trump: the 9, 10, and left bower. If you visit that page to which I linked, you'll see some statistics that I ran which indicate this is a great tactic!

Finally, the Euchre bots will now always go alone when they have 5 trump cards. The logic goes like this: Suppose you have 5 trump cards. That's an excellent hand, and in the worst case you have the lowest 5 trump: 9, 10, queen, king, and ace. So let's look at this worst case. If your partner has the two bowers, then not going alone will help you get 2 points. However, going alone will ensure you get 4 points! Which is better? The 4 points, of course, so you should go alone. And what if your opponents have the left and right bower? Well, you'll only get 1 point, anyway, whether or not you go alone. There's exactly one case where your partner might help you get 2 points instead of 1 point. Suppose your partner has the right bower, and one of your opponents has the left bower. In that scenario, by going alone, you're going to get only 1 point instead of 2.

In the long run, the risk of getting only 1 point vs 2 is outweighed by the benefit of getting 4 points when going alone. Most of the time, your partner won't be able to help you, and it benefits the team to take the risk.

I hope you find that these changes in the Euchre bots make them a little better as a partner!
Should I order up?