[noneeeed]

Likewise. I've always been curious as to just how significant an impact all this behavioural ad-serving actually has on the impact of their marketing budget. We assume that things like AdSense must provide better ROI than simple dumb placement of ads, but I'd love to know if that is actually true over the long term, and if so just how much better it is. For example, it might work well in the short term for certain things, but at the expense of long-term broarder brand awareness perhaps.

However I suspect it would be fiendishly difficult to work out the effect over anything other than the immediate short term (i.e. impression to click to sale).

If anyone knows of some good experimental work on this I'd love to read it.

[yowlingcat]

I'd love to read some good experimental work on it as well. Off the top of my head, I can guess that there's some benefit to retargeting ads up to a point -- if you can show an ad sequence over time, there's probably an argument to be made that the spaced repetition is more effective than just showing the same ad over and over again, for certain kinds of ads. Then again, that gets back to ad design in and of itself -- a clever campaign could go viral and/or engage in a way an A/B optimized campaign with a poor concept probably never will. With something that's part art/game theory/design and part data, I'm really curious as to how you could even design a reasonably lossless experiment to accomplish this.