ek@l,

Don't get frustrated by 3 rejects. Personally I know one guy whose visa is rejected 5 times, sound unbelievable. But he didn't stop going for interview and eventually he was given visa probably consular thought that guy won't give up.

Sometimes, your number of attempts gives you an advantage rather than disadvantage (provided you have all the documents).

And Ek@l  you have to remember one thing, you being in US infact makes your case of wife stronger than weaker depending upon how your wife faced the interview. When I applied overseas my parents were already in that country, but I didnot present myself as if I was going to see the parents. Infact when they asked me why do i want to go in their country , my answer was mostly related to my subject of study and not related to parents at all.

It all depends on your wife..........here are tips.........

a. Your wife shouldn't  appear as if she is coming to see you. She should show how important that study is for her.

b. Show consular that she is serious about her study. Show GRE, GMAT , TOEFL, TA, University accommodation and other documents. Show everything possible that shows she is serious about her study.

c. Don't give up trying. it is just matter of time before they allow.