Every first-year economics student quickly becomes familiar with charts of supply and demand, which place price on one axis and quantity on the other. Given a drop in demand, the charts show, firms can either sell fewer items at the prevailing price or cut prices to prop up sales. But online retailing, which makes it easier to collect fine-grained price data, reveals how poorly textbook models reflect real-world market dynamics. The prices of consumer goods, it turns out, behave oddly.
Cut-price economics － The Economist August 10th 2019 消費財の価格メカニズム
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