According to Roenneberg, age also has a big influence on chronotype.

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Steer says Canaries' number one John Ruddy has been a big influence since signing from Everton in 2010.

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The arrival of Peter Thompson on loan during the January transfer window has had a big influence on the team.

BBC: Roy Coyle's view

But in its five years, Diamond has become a big influence on the ways corporate titans rethink their Web economic strategies.

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"Sunlight has clearly had a big influence, and Vanguard is the one company everyone thought was probably doing a good job, " says Donald Phillips, managing director of fund tracker Morningstar.

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"Big Brother has so much influence on fashions among young people, it could have a really interesting impact on the way young people perceive the Welsh language, and also how many people want to learn it, " he said.

BBC: NEWS | UK | Wales | Big Brother's warning over Welsh

It has a big role to play in a dangerous region, as well as considerable influence among developing nations.

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While its influence on big-ticket issues in the region is declining, the U.S. has redoubled efforts to tackle their root causes, such as poverty, hunger and disenfranchisement of women.

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