Why more South Asian than East Asian CEOs?

Analyses revealed that East Asians faced less prejudice than South Asians and were equally motivated by work and leadership as South Asians. However, East Asians were lower in assertiveness, which consistently mediated the leadership attainment gap between East Asians and South Asians. These results suggest that East Asians hit the bamboo ceiling because their low assertiveness is incongruent with American norms concerning how leaders should communicate.

That is from a new piece by Jackson G. Lu, Richard E. Nibett, and Michael W. Morris, via the excellent Kevin Lewis.