Defending from the blinds

What is the optimal rate to defend from the blinds to make it -EV for a steal. I'm not really sure how I would calculate it. I'm guessing you'd have to figure out when it becomes profitable and how many times they have hands that get made or are good. People say good rate to steal at is 1/3 of the time. We'll use that for example. By betting 4 to win 1.5 at micro. You would need to take it down. I'm really not sure how to calculate this. Because you have to take into account times they have good hands. Has someone already done this or can someone tell me how I would go about calculating it out.

spoonitnow dd this a while ago - http://www.flopturnriver.com/phpBB2/...ense%20defence
however, remember you're playing micros. Most people aren't stealing. I only rarely defend even at 50nl...

I learnt not to defend the hard way. I'd read loads about blind defence in mid-stakes 6-max and decided to apply it playing 25nl. I ended up with A7 s on a 3-bet AK7 board. I still carry the scars..

blind defence is a silly concept below 50nl.

sorry, would explain more, but I'm 11-tabling a mixture of 6-max and fr 50nl, and a few tables are playing a little tough.
Good luck.