Airlines say they most often pick trips randomly, and sometimes target problem flights to measure how employees responded to trouble.

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Schools are trying to get ahead of the problem by implementing baseline testing to measure cognitive ability before and after an injury.

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It's complex because it's difficult to measure our taxable income and that is a problem regardless of whether or not you use progressive marginal rates or a single flat rate.

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But the bigger problem is that the measure will be a compliance nightmare for the Internal Revenue Service and smaller businesses.

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And if I could wave a wand, I'd love to have a way to measure how exposure to risks like disease, infection, malnutrition and problem pregnancies impact children's potential their ability to learn and contribute to society.

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Both senators said Monday that part of the problem involves misconceptions about their compromise, and they urged colleagues to read the 49-page measure instead of relying on what they called erroneous political rhetoric by opponents.

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Unfortunately, no matter how regions are divided, they are arbitrary, and there is no practical way to measure regional inequality that does not encounter this problem.

ECONOMIST: Letters

So the fact that in a global economy a problem in Europe could affect our economy only reminds us and reinforces the fact that we need to take every measure we can on the issues that we control, to ensure that our economy keeps growing and it keeps creating jobs.

WHITEHOUSE: Press Briefing