When helping people learn Planning Poker I always ask what will happen if one person plays/says their estimate before anyone else. Many people usually spot the problem and they call it “influence.” And they’re right. Sometimes a wise person says, “but I won’t be influenced”. The science of “anchoring” is well known but until recently I couldn’t think of a personal example that illustrates the problem. Happily a recent trip to San Francisco solved that problem.
I was shopping for a new pair of pants. My expected price was $75 for a decent pair of khakis. My first stop was Hugo Boss which sold very casual khakis for $150. I thought, “No way! Far too much money.” In the next few stores I saw several more pairs of pants at $100-120. But fifteen minutes after I first saw the $150 pants, I bought a pair for $100 in Bloomingdales (10% discount because I’m a Canadian). I was happy to get such a bargain. After an insanely long walk back to my hotel I realized what had just happened. Seeing the $150 pants reset my price point and now I thought that was the high end and that $100 was “reasonable”. Luckily I didn’t buy two pairs, which was my original intent.
Anchoring is subtle and it can be pernicious. One comment that really stuck with me in this area came from Dan Airely- even with everything he knows about these kinds of biases and errors he still makes these mistakes.
That is why Planning Poker estimates are done blind, no pre-conversations about the estimate.