As long as the economic incentives are for academic researchers to produce far more PhDs than are needed to replace themselves**, we will continue to have this problem. ...
** Even a modest training regime – let’s say, one student for a six year period with no overlap between students – will result in five students during a faculty member’s career.
What is missing from this analysis, though, is a population view. The size of a population depends on birth, death, immigration, and emigration. The quote above focuses on just one aspect of that: academic “birth,” and even that is incomplete.
To continue using the reproductive metaphor, not every academic “parent” will have offspring. Indeed, many academics, because of the institution they are at, will never train a Ph.D. student in their life. We have a situation much like that of highly competitive animals like bull elephant seals: you have super winners who have many offspring, and super losers, who have none.
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