110-joshua-gans.jpgIt does not take a genius to work out that ads for strollers are likely to be wasted on parents with older children or that you shouldn’t put a Starbucks ad in front of someone who doesn’t drink coffee. But how can you tell who is really looking at your ad? This week Google publicized various innovations it is bringing to display advertising that are designed to generate a better match between what is displayed and what a web surfer might actually want to buy.