Utilize the input text as a context reference, choose the right relationship between Joe Kaeser and Siemens from the options. Options: product/material produced, manufacturer, distributed by, industry, position held, original broadcaster, owned by, founded by, distribution format, headquarters location, stock exchange, currency, parent organization, chief executive officer, director/manager, owner of, operator, member of, employer, chairperson, platform, subsidiary, legal form, publisher, developer, brand, business division, location of formation, creator.

Siemens Chief Executive Joe Kaeser described the dilemma last month, explaining why Siemens continued to partner with Shanghai Electric despite the Chinese company's having become more of a direct competitor.
employer