Thank you all for your wonderful comments. I now have some concrete directions to look. I must say it is much harder than I initially thought.
Are there companies employing any of these techniques to provide some service? This seems to be the next step up from keyword-based search. I remember seeing some startups providing a gauge of positive press coverage on stock symbols. How do they do it?
For one example, I've seen a couple of sites that classify Twitter posts about movies as positive or negative. I don't know what techniques they're using.
Are there companies employing any of these techniques to provide some service? This seems to be the next step up from keyword-based search. I remember seeing some startups providing a gauge of positive press coverage on stock symbols. How do they do it?