Stata is not new to Yahoo. He previously served as Chief Architect and will be effective immediately assumed his new duties in the near future.
Stata will then be responsible for all of Yahoo's technology and will lead the strategic direction of the company's technology policy. In this he is not located directly under the CEO Carol Bartz, but the CPO Blake Irving.
Yahoo previously as Chief Architect, he was very good in terms of search engine Yahoo.Besides running Stata also clever advertising platform Yahoo.
Quoted from Neowin, Friday (6/4/2010), before joining Yahoo in 2004, he sold his property company called Stata Labs to Yahoo.
While Ari Balogh as CTO before, withdrew for personal reasons which can not be said publicly, shortly after Yahoo hired Microsoft executive, Irving Blake as a CPO.