The Fallacy of Supply and Demand
A chapter summary from Predictably Irrational by Dan Ariely.
Standard economics assumes that prices reflect the underlying value of goods, determined by supply and demand in a market. Ariely's chapter argues that price is far more arbitrary than this picture suggests. Prices are anchored — set by reference points that often have nothing to do with the underlying value of the product.
The chapter's lab experiment had participants write down the last two digits of their social security numbers, then bid on various items in an auction. Participants whose SSNs ended in higher numbers consistently bid higher for the same items. The number was random, but once it was in mind it served as an anchor that shaped subsequent valuations.
The argument generalizes to consumer behavior. The price of any new product category — when smartphones first appeared, when bottled water first appeared, when streaming subscriptions first appeared — is anchored by whatever the first widely-publicized price was. Subsequent prices for similar products cluster around the anchor regardless of whether the anchor reflects any underlying value. Markets do clear, but they clear at price levels that are partly arbitrary historical accidents.
The chapter's deeper implication is uncomfortable for economic theory: if prices are partly arbitrary, then the welfare-maximizing claims of free markets are weaker than the standard story suggests. The practical implication for individuals is to recognize that the price tag on most products has only a loose connection to what the product is actually worth, and to evaluate purchases against personal value rather than against the prevailing market anchor.
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More from Predictably Irrational
Predictably Irrational sits in a curated reading path — each pairing it with other books that sharpen the same idea. Three nearest peers:
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