Analysing data to calculate impact of Social Media

Those geniuses [or is it Genii?] in our data dept reckon they might be able to help out in my quest to come up with a way of measuring the impact of social media on sales. Woo Hoo!!

A quick chat with the smart, urbane, witty and surprisingly well dressed Mark, or the 'data-modeling-king Mark' as he is known to his friends, reckons he has done something similar for our client Sainsbury's Bank. 

He took three years of online sales data and looked at when campaigns ran, correlated them to sales trends and accounted for seasonal trends and other external factors and came up with what presence in different sites lead to increases in sales. This is where I bow down in awe and chant:

"we're not worthy"

Ok, the task of getting three years sales data and details of all sales and marketing campaigns for one client may be in the same league as a young man in a loin cloth facing down a Kracken - but Perseus persevered and won.

I'm hoping with the help of the McCann 'data deities' and with valuable thinking [already] from Chris, Paul, Amelia and Jonathan, we might just get somewhere [either that or die a futile death in the belly of a fictitious and slightly unrealistic Norwegian sea monster].