Hello,
I have a question regarding a doubling decision in a 3 point match.
Let's say I am white and the score is 0-0.
Earlier in the game I was at a disadvantage, and accepted a cube from black.
So I have the cube at 2 level, and the game is nearing the end at the bearoff stage, so there are no gammons.
I am a slight favorite to win now, let's say 55%.
Is it correct for me to redouble to 4 and put the whole match on the line?
The opponent would not be able to recube because the match is only to 3.
Thanks for any help.

If it's the last roll of the game, absolutely you should double. If it's not the last roll of the game, you could theoretically have a double, but probably not, 55% is pretty low.

You might think "I'm ahead and so why wouldn't I want the game to be worth more?" And yes, if it was a choice between doubling now and doubling never, you would do better to double now. But the fact that you will opportunities to double later makes it better to wait.

I'll describe a situation where it's trivially correct to wait. Say you have no chance to "lose your market" over the next two rolls (yours and your opponent's). That is, even if you roll your best number and your opponent rolls his worst, he'll still have a take. So, even if things go well, you didn't lose anything by not doubling -- you can still get the cube to 4. But if things go badly, you'll be happy you didn't double.

Now say you have a 1% chance to lose your market. You might want to double because if you don't and that 1% comes in, then you'll regret having not doubled. But there's also the other 99% to worry about. Some of that 99% is things going badly for you, and you'll regret having doubled in those circumstances.

So generally, you'll want to be closer to your opponent's take/pass point before doubling so you have some reasonable chance to lose your market.

At this score (0-0 to 3, with you holding a 2-cube) you can double a little earlier than normal because you're giving your opponent a dead cube, rather than a live one. But you still need a solid advantage, and 55% doesn't quite qualify.

In a pure race at this score and cube position I think most of your correct doubles will occur when you're around 65% to win.

I understand, it's more clear now
Thank you for the explanations!