The sampling error for Wednesday's results is plus or minus 4.5 percentage points.

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While headlines focused on the unexpectedly low 32, 000 new jobs turned in by the payroll sampling, the media ignored the astonishing results of the household survey--a creation of more than 600, 000 jobs.

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Results of any sample are subject to sampling variation.

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They insist that sampling, when applied correctly, can yield very accurate results.

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Results for the full sample have a margin of sampling error of plus or minus 3.9 percentage points, it is larger for subgroups.

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The results of the poll, conducted nationally by telephone between Friday and Sunday, has a sampling error of plus-or-minus 3 percentage points.

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More recently, sampling by the U.S. Army Corps of Engineers and other federal agencies also yielded positive results in the Chicago waterways.

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