Well lets see, if you take everyone's yields regardless of strain and growing conditions remembering all the ones that died along the way or were killed by newbies that didn't do any research, I'd say average would be about 1 gram give or take a gram. VV
Really? You think that would be the average? I was thinking more along the lines of 10lbs +/- 10lbs or so.
It's sort of ridiculous to ask such a wide open question. At least throw in indoor vs. outdoor and what kind of light. Then maybe we can start ballparking, but really it's going to depend.
Outdoor: Depending on your location you may have already missed the boat on that one.
Indoor: With a 400w HPS in a decent size space I would estimate that you will get ~1 oz per plant in 3 months. That's if you do everything correctly and use soil. Chances are you won't do everything correctly so it will either A) Take longer, B) yeild less than that or C) just completely die off anyway.