Ultimately, everyone has their own personal threshold as to how much risk they feel they can take.

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So the real controversy is what minimum level of solar energy at 65N is the threshold for the descent into an ice age and how unstable the weather becomes near that threshold.

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Even before reading their article, it could be guessed (correctly, as it turned out) that the 90 percent threshold was more an artifact of how the data were selected and grouped rather than anything resembling a natural law.

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Instead, Mr Blunkett wants to raise this threshold, but has not decided by how much, so the effect on the money raised is uncertain.

ECONOMIST: Universities

"Hello, Professor Warwick, " his PC announced when Warwick crossed the threshold of his office, before casually mentioning how many E-mail messages he had received.

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As to timing, Mr Perkovich explains how India was yanked across the nuclear threshold for crude party-political reasons.

ECONOMIST: India

Exactly how far owners try to lower the threshold will determine whether there's really a major confrontation, Rishe thinks.

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Douglas Back built Widget the People, a tool that lets you create an embeddable thermometer showing how many signatures your petition needs before it reaches the response threshold.

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Mr. Laffer, chairman of Laffer Associates and the Laffer Center for Supply-Side Economics, is co-author, with Stephen Moore, of "Return to Prosperity: How America Can Regain Its Economic Superpower Status" (Threshold, 2010).

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The Green Party said it did not know how many workers sub-contracted by the councils are paid less than the poverty threshold.

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