Yesterday, I was speaking with Hal Varian, Chief Economist at Google after a lecture at the local University. One of the things I asked him about was tracking off line conversions. For our customers with bricks and mortar stores this is a common challenge.

Hal suggested one way of measuring off line conversions was to run a Google campaign and use the geotargeting options to exclude an area around a subset of your stores which can then be used as a control. You can then compare the in-store sales data for the control group to the others to measure the offline impact of the AdWords campaign.

This sounds like a good idea to me – it’s similar to the technique used to measure the impact of traditional advertising. I presume if you look at the proportion of your total traffic that came from the Google campaign then you can extrapolate to estimate the total offline sales contributed by your website. This is really useful information. I know a number of our customers struggle to get recognition for the contribution the website makes to offline sales. I’m sure it is significant.

You could run a similar trial with your email marketing – using the addresses of your customers who receive your newsletters to restrict the newsletter to certain geographies. 

On a kind of related note – I remember my father telling me that he always sold more chicken in the months when the TV ads were running. Thanks to YouTube you can see his chicken advert: