observational

from WordNet (r) 3.0 (2006)

observational
    adj 1: relying on observation or experiment; "experimental
           results that supported the hypothesis" [syn:
           {experimental}, {data-based}, {observational}]

from The Collaborative International Dictionary of English v.0.48

Observational \Ob`ser*va"tion*al\, a.
   Of or pertaining to observation; consisting of, or
   containing, observations. --Chalmers.
   [1913 Webster]

[email protected]