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Representatives attending the 1921 Conference on Unemployment held in  Washington  D.C. President Warren Harding convened a President's Conference on Unemployment at the instigation of then Commerce Secretary  Herbert Hoover  as a result of rising unemployment during the recession .
 employee of: Washington, Herbert Hoover
Given options, please tell me the relationships of all the listed entity pairs.Output format is "relation1: word1, word2; relation2: word3, word4". 
Option: cities of residence, top members employees, members, alternate names, origin, state or provinces of residence, title of person, spouse, city of headquarters, NA, founded by, state or province of headquarters, employee of, countries of residence, country of birth, founded, subsidiaries, country of headquarters 
Text: {0} 
 Entity Pairs:  Washington, Herbert Hoover 
Answer:
 employee of: Washington, Herbert Hoover