What is the relationship between 'Janet Yellen' and 'President' in the context of the input sentence.
Options: position held, owned by, platform, stock exchange

(1330/1730) Also, Federal Reserve Bank of San Francisco President John Williams speaks on the economic outlook before the UCLA Anderson Forecast for the Nation, State and L.A. (1700/2100) LIVECHAT: FX WEEK AHEAD with Reuters FX analyst Jeremy Boulton Join Reuters FX analyst Jeremy Boulton for a chat about foreign exchange markets and whether the dollar will build on gains this week made after Fed chair Janet Yellen signaled U.S. rates would head higher before the end of the year.
position held