Tico, valid statistics aren't about "one instance", they are about facts as a whole. There are anecdotes about people who have died as a result of them wearing a seat belt. This doesn't change the fact that wearing a seat belt makes you (or people in general) much less likely to die in an automobile accident.
I think you are missing my point in general.
Any bunch of anecdotes I give you aren't going to reflect any objective facts... they are going to reflect my prejudice. That is what anecdotes are for. I select them to support my preconceived notions.
Valid statistics, on the other hand, are gathered through an open, objective process that may or may not contradict my personal bias.
I have seen valid statistics contradict the pre-conceived opinions of the people who gathered them (in fact, I have seem them contradict my own pre-concieved opinions).
Have you ever seen someone give an anecdote that has contradicted their personal bias?