An anecdote is usually a short narrative of an interesting, amusing, or biographical incident. Anecdotal are sometimes the starting point of a proper investigation, but it is all too often the ending point and every point of a pseudo-investigation.
Man prefers to believe what he prefers to be true.
– Sir Francis Bacon
There is a broader statement about those believing in anecdotal evidence, either found by themselves or heard from others. Anecdotal evidence is often used in politics, journalism, blogs, and other contexts to make or imply generalizations based on very limited and cherry-picked examples, rather than reliable statistical valid studies.
You can do little with persons who are disposed to accept these curious ... superstitions. You have no fulcrum you can rest upon to lift an error out of such minds as these, often highly endowed with knowledge and talent, sometimes with genius, but commonly richer in the imaginative than the observing and reasoning faculties.
– Oliver Wendell Holmes MD, in remarks to graduating class of Bellevue Hospital Medical College in 1871.