A study released last Friday by Hitwise is causing lots of discussion: graphing search engine use against some of their demographic data, they assert that people who use Yahoo tend to buy less stuff online. To which anyone working in search replies, no duh! Client after client, our data shows that while impressions and even clicks from Yahoo might be fairly even with Google, Yahoo pretty much never equals Google in what really matters: conversions. People who use Yahoo just don’t buy stuff like Google users do. Our intuition has always been that these users are younger (and thus less likely to be affluent); data like this backs up that intuition.