7. Confirmed (photo, tracks, indisputable kill)
6. Probable (right color, right size, can describe the tail etc.;  The knowledge of the outdoors of observer increases the odds that the sighting is probable. )
5. Likely (some evidence consistent with lion but lacking or weak on one or more of the criteria used in the probable category).
4.
3. Possible (some evidence but also some that raise doubt about lion as interpretation.
2. Could be but not real likely
1. Unlikely
0. Evidence that is clearly inconsistent with mountain lion.