Academic tenure, risk-taking and the diversification of scientific research

We discuss two competing hypotheses linking the relative job security granted by tenure in academic employment to scientists’ choices between diversifying vs. specialising their research portfolio. To test our hypotheses, we develop a new methodology, using an algorithm of semantic analysis that partitions scientists’ publications into research themes, and we compute the Blau’s diversification index for 562 scientists observed over 15 years. The...