The demand and supply model predicts that a larger relative net supply of a particular educational group will negatively affect its relative earnings. To test this, we use the opening of Aalborg University as a natural experiment, because it created a shock to the supply of electrical and construction engineers in Denmark in the 1980s. The results show that when the supply of electrical and construction engineers peaked, their earnings dropped relative to a comparison group of chemical engineers, which Aalborg University did not supply at the time. Hence, we conclude that even the earnings of engineers, who are in high demand, are susceptible to supply effects.

中文翻译：

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供求效应和大学教育的回报：来自丹麦工程师的自然实验的证据*

需求和供应模型预测，特定教育群体的较大相对净供应将对其相对收入产生负面影响。为了测试这一点，我们将奥尔堡大学的开放作为自然实验，因为这对1980年代丹麦的电气和建筑工程师的供应产生了冲击。结果显示，当电气和建筑工程师的供应量达到顶峰时，相对于化学工程师的比较组，他们的收入下降了，而奥尔堡大学当时则没有。因此，我们得出结论，即使是需求量很大的工程师的收入也容易受到供应影响的影响。