Cities close together in the standings may have very different prices, while others further apart can be effectively level with each other, taking into account margins of error for price and expenditure data, which the firms don't share with the public.

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Later that month a representative indicated that the capital gains distribution credited to her account was a computer error.

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Having established the reality of his point, he then designed a mathematical model that tried to take into account and quantify sources of error.

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Also, take into account the possibility of human error.

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When the margin of error is taken into account, Labour could actually be behind the Conservatives.

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Keeping a cushion in your account will cover you in emergency situations and absorb the occasional accounting error.

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In June, a programming error temporarily allowed any password to be used to access any account.

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Any real-time account of what happened that night is likely to be fraught with mis-remembering and error.

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For example, if you were visiting Mashable and logged into our site using your Facebook account (and you were also signed into Facebook), you were automatically redirected to a Facebook error page.

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