Model truth-seeking and testing of hypotheses

A really rather good series of three articles explicating the value of majoring in Economics and then exploring the causative channels that bring about the positive outcome documented. Excellent in the sense that it is an exploratory seeking of truth, positing causative mechanisms and then testing whether the evidence actually supports the hypothesis. The series illustrates that even something as straightforward as the link between education major choice and future income is enormously complex. Sinick explores five hypotheses for superior economic major income performance.

Human capital acquisition.
Acquisition of a desire to make money.
Pre-existing ability as measured by tests.
Pre-existing desire to make money.
Signaling.

Sinick concludes that there is insufficient evidence to support any of the hypotheses in any sort of robust fashion, other than number 3, the link between pre-existing ability and future income.

The three articles are"

Earnings of Economics Majors: General Considerations by Jonah Sinick

Economics Majors and Earnings: Further Exploration by Jonah Sinick

Human Capital Or Signalling? No, It's About Doing the Right Thing and Acquiring Karma by Vipul Naik