With earnings reporting season on, here is a very interesting and bold insight into what is happening in the markets: http://www.bloomberg.com/news/articles/2015-11-02/socgen-slams-the-corporate-cheating-season.
The gist of it is that "...investors can credit the robust equity market returns in October to "the charade that is quarterly company reporting."" In other words, Soc Gen analysts show that "corporate executives are able to lower the bar for what constitutes success since August 2008" so that "analyst upgrades relative to downgrades rise during periods in which many companies report earnings."
In simple terms, markets optimism is overhyped by artificial under-hyping at the estimates point in order to trigger positive surprise. And this comes on foot of massive equity buy-outs (often using debt) and other shenanigans. EMH, anyone?..
Which brings us to a perfect summary of the 'glass 1/10th full' the markets run on:
You can't make it up...