I just looked, and in terms of the definition of sex offender, at least for Illinois, they tell you exactly what the conviction was for, and the age of the victim. So it's pretty highly specific.

Civil rights qualms aside (which I definitely have about this), it's a fascinating map. lines are drawn so sharply along the race and class lines in my neighborhood. Is it because poorer people are more likely to lash out at others because of economic stress? Or is it because there's a much higher conviction rate among black men in general in this country? I couldn't find a single white guy on my map, which seems like a statistical impossibility, doesn't it?