Traffic stats?
sing it with me now...
let Pd repesent the price of the domain
we're given that P(d+/-L) > Pd...where changes in the letters would increase the value of the domain...i.e. the domain is a typo
we can write Pd=f(T) where price of the typo is a function of the TRAFFIC the name receives. :p
Moral of the story...if you post a typo, post the traffic, otherwise no soup (err.appraisal) for you!