Roger
Paranormal Novice
Good points. I think we suffer from a lack of information. If the Universe is indeed "teeming with life," resources, water, etc. where nearly every star has at least one planet supporting life, then that's one thing. If the Universe is such that a planet like ours is quite rare, the value goes up, and so does the competition. Of course, we have theorists who claim both extremes, but we still don't really know.
I don't think that planets like ours are extremely rare considering the discovery of multiple bodied star systems in our local galactic neighborhood. I don't think an extrapolation to the rest of the galaxy is too far fetched, nor to other galaxies.
The distribution of elements in a galaxy is a fairly well known proportion; however, the production of elements in a particular galactic region would depend on the frequency of occurrence of supernova, which produce the elements. If a particular element was a resource of interest, perhaps there would be an interest in the heavier elements which are a smaller piece of the elemental distribution pie. If this was the case, then local planetary sites with concentration of these elements could be of interest (e.g. uranium in Canada or Russia). Other rare isotopes or compounds could potentially be of interest. Correlation of these sites of interest with sightings might yield a significant correlation (or not...).