  Strikingly few Nobel laureates within medicine, natural and social sciences
are women. Although it is obvious that there are fewer women researchers within
these fields, does this gender ratio still fully account for the low number of
female Nobel laureates? We examine whether women are awarded the Nobel Prizes
less often than the gender ratio suggests. Based on historical data across four
scientific fields and a Bayesian hierarchical model, we quantify any possible
bias. The model reveals, with exceedingly large confidence, that indeed women
are strongly under-represented among Nobel laureates across all disciplines
examined.
