This is a funny story that happened earlier this year, it was on Tuesday Feb 8th, 2007, the first day immediately after Yahoo launched the new Panama backend for sponsored search results.
Yahoo has a real-time tracking system (RTTS For short) that reports search activity (PVs, clicks, CTR) on a minute-by-minute basis, that system is also hooked into the alerting/paging systems. Anyway, since this was the first day of Panama, every body was watching these realtime graphs like a hawk.
The day started well, and the click volume was higher than last week as our testing predicted, but then around 1:10pm (pacific) the sponsored CTR metrics (i.e. clicks/pvs) took a rather alarming dive. This is a bit of an exaggeration, but imagine red lights flashing every where, a siren sound similar to that in submarines, people running every where, pagers beeping relentlessly, play-book procedures getting activated, hearts falling to the ankles, etc.
It took us about 20 minutes to realize that the problem was Anna Nicole Smith. You see, the news about her death came out around that time, that lead to a huge spike in searches for her name, some advertisers were bidding on her name, but most folks were searching then clicking on the news results we show at top of the search page, hence it looked like the overall sponsored CTR was tanking.
From that day on we have a cool name for such false alarms, and that is the “Anna Effect” 🙂