Simulations

I'm going to start a series of posts simulating outcomes in various bidding situations. I'll try to clearly list the assumptions in each case.

One problem that I can't easily do anything about is the difference between double dummy analysis and results that occur at the table. I'm not sure if any research has been done into quantifying this, but if it has, please let me know.

The big advantage for declarer playing double dummy are that missing cards (e.g. queens) can always be located and singleton kings offside always drop. The bid advantage for defenders are they always find the best opening lead and single dummy defence is just hard because you can't see your side's combined resources in they way that declarer can.

In slam contracts, I think declarer will take more tricks double dummy. This is just because there are fewer decisions for the defence when they hold fewer high cards. Not that defence against slams isn't important, but declarer gets a higher percentage of the tough decisions in slams compared to games and part scores. As a general rule, I'd guess that the higher the contract, the more double dummy analysis inflates the number of tricks taken by declarer. In a contract such as 1NT I expect the defence to do better double dummy than in real life.

If there is a significant difference between tricks taken double dummy and in real life, my conclusions will be wrong by that amount.