Because there is a big selection bias in university education, it&#x27;s hard to say that Harvard caused someones income to go up using your math. I prefer this post from last year which tries to calculate value-added.<p><a href="http:&#x2F;&#x2F;www.economist.com&#x2F;blogs&#x2F;graphicdetail&#x2F;2015&#x2F;10&#x2F;value-university" rel="nofollow">http:&#x2F;&#x2F;www.economist.com&#x2F;blogs&#x2F;graphicdetail&#x2F;2015&#x2F;10&#x2F;value-u...</a>