Excercises for improv and playing by ear

[cacci]

I have been playing piano for around three years.  However, I have rarely had lessons and do not read sheet music, but would rather learn in a way geared to increase the ability to play improv and by ear.
As I do not have a teacher or perfect pitch, what are the best exercises I should practice?  Should I focus on scales and hanon finger exercises?  Until now I've been practicing by learning pieces online and mimicking the playing styles of others.

[ted]

Improvisation does not exist in a vacuum. The more varied your musical stimuli, the better your improvisation will be when you develop it. Also, do not forget that without exception the old masters were wonderful improvisers. Everything influences everything else. Therefore look for a good, broadly talented teacher with a creative bent. Learn the classics properly, learn to read and write music, learn everything you can. Reject nothing, especially if you are young. If improvisation is to come then it will  come regardless. Perfect pitch, as far as I know, is neither necessary nor sufficient for improvisation.