Do Long Page Titles Improve Search Rankings?

Some people have observed that longer titles on web pages have done them a favor: higher likelihood of good rankings on search results. While I think this should be coincidental, as shorter titles are believed to retain the focus of these terms, the only way to find out is to throw a few terms and observe search results.

Let me try a few:
pneumonia prevention
First two results have very short page titles.

azerbaijan folk songs
While most results yield long titles, two of the first six actually had three words or less.

paella recipes
The longest page title in the first page of results is “Paella Recipe – An Authentic Spanish Paella Recipe from Madrid”. All the rest have six words or less and two of them have “Paella Recipe” only as page titles.

One question I have is what is the definition long and short page titles? Are long titles those that exceed the displayable content? Are short titles composed of 15 characters or less?

Maybe it’s my choice of search queries but I’d still vouch on my earlier statement that the searches observed are coincidental and that many other factors influenced pages to rank high, one of them is the page title but not the length of the title.