"People call them unicorns..." ☛ Data Scientists that is... - wsj.com

"People call them unicorns" because the combination of skills required is so rare, said Jonathan Goldman, who ran LinkedIn Corp.'s LNKD +0.66% data-science team that in 2007 developed the "People You May Know" button, which five years later drove more than half of the invitations on the professional-networking platform.

Employers say the ideal candidate must have more than traditional market-research skills: the ability to find patterns in millions of pieces of data streaming in from different sources, to infer from those patterns how customers behave and to write statistical models that pinpoint behavioral triggers.