諾貝爾獎獲獎演說(PDF 31頁）

We have all visited several stores to check prices and/or to find the right item
or the right size. Similarly, it can take time and effort for a worker to find
a suitable job with suitable pay and for employers to receive and evaluate
applications for job openings. Search theory explores the workings of
markets once facts such as these are incorporated into the analysis. Adequate
analysis of market frictions needs to consider how reactions to frictions
change the overall economic environment: not only do frictions change
incentives for buyers and sellers, but the responses to the changed incentives
also alter the economic environment for all the participants in the market.
Because of these feedback effects, seemingly small frictions can have large
effects on outcomes.
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