a corollary to wanamaker's law - for measures of influence

You know the old advertising chestnut from pioneer retailer and ad man John Wanamaker, ""Half the money I spend on advertising is wasted; the trouble is, I don't know which half."

What if the same was true in the measures used to value influence and brand awareness and word-of-mouthiness in our complex networked online world? What if we really need to throw out half our metrics, half our assumptions? Which half would you pitch?  How much gut can you trust in your decision-making? Whose pattern recognition algorithms would you spend money on...

Currently immersed in Nathan Gilliatt's Guide to Social Media Analysis, a thoroughly researched and thoughtfully compiled canonical directory of the current landscape of social media analytics. Gilliatt can rightfully stake a claim as a domain expert here.