Like most people, I like to think that my choices are a result of clear, rational thought. However, our decision processes are far more heuristic than we admit. Two new articles on choice bear this out:
Mantonakis and colleagues studied how the order of items presented to us affects our preferences and choices. In their experiment, several wines were presented to participants to taste and rate. Although participants were told that all wines were from the same varietal (e.g. pinot grigio), in reality, all of the samples were from the exact same wine! If preference and ratings were rational, then the average rating a wine receives by subjects should be the same regardless of whether it was tasted first or last. However, they found that the first wine tasted by participants was preferred over wines in other serial positions, a finding known as the primacy effect.
In the second paper, Krajbich and colleagues modeled decision choices made by subjects between two pieces of junk food. Krajbick brought junk-food-loving, hungry participants into the lab, and asked them to rate how desirable 70 different junk foods are to them. Then, in front of an eye tracker, they were presented with pairs of pictures of these food packages and asked to decide which they would prefer to eat after the experiment. Unsurprisingly, people are quicker to decide when the value of the two choices is very different. However, when the decision is more difficult, participants tended to choose the item they looked at more.
Both of these studies are laboratory demonstrations of things advertisers seems to have known for a while: to get you to buy their product, getting you to look at it early and often might be enough to get you to buy it.
Mantonakis, A., Rodero, P., Lesschaeve, I., & Hastie, R. (2009). Order in Choice: Effects of Serial Position on Preferences Psychological Science, 20 (11), 1309-1312 DOI: 10.1111/j.1467-9280.2009.02453.x
Krajbich I, Armel C, & Rangel A (2010). Visual fixations and the computation and comparison of value in simple choice. Nature neuroscience, 13 (10), 1292-8 PMID: 20835253