In contract theory, signalling (or signaling; see spelling differences) is the idea that one party (termed the agent) credibly conveys some information about itself to another party (the principal). For example, in Michael Spence’s job-market signalling model, (potential) employees send a signal about their ability level to the employer by acquiring education credentials. The informational value of the credential comes from the fact that the employer believes the credential is positively correlated with having greater ability and difficult for low ability employees to obtain. Thus the credential enables the employer to reliably distinguish low ability workers from high ability workers.
adding page this day (skills gap et al)
While the labor market rewards good grades and fancy degrees, most of the subjects schools require simply aren’t relevant on the job. Literacy and numeracy are vital, but few of us use history, poetry, higher mathematics or foreign languages after graduation. The main reason firms reward education is because it certifies (or “signals”) brains, work ethic and conformity. It’s therefore sensible, if unseemly, for students to focus more on going through the motions than acquiring knowledge.
Ponder this: If a student wants to study at Princeton, he doesn’t really need to apply or pay tuition. He can simply show up and start taking classes. As a professor, I assure you that we make near-zero effort to stop unofficial education; indeed, the rare, earnestly curious student touches our hearts. At the end of four years at Princeton, though, the guerrilla student would lack one precious thing: a diploma. The fact that almost no one tries this route — saving hundreds of thousands of dollars along the way — is a strong sign that students understand the value of certification over actual learning.