What is the definition of devaluation of education? How to measure it?

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Devaluation of education refers to the perceived reduction in the value of diplomas and degrees, often resulting from an oversupply of educated individuals relative to available job opportunities. This phenomenon can manifest as "credential inflation," where the economic return on educational qualifications diminishes as more people attain higher degrees without corresponding increases in job demand.

To measure devaluation, researchers may analyze labor market outcomes, such as wage differentials and employment rates for degree holders, alongside the alignment of educational qualifications with job requirements.