One, these high marginal tax rates create "poverty traps" that keep the poor poor, and make escape to the middle class difficult.

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It is important that these people not get stuck in poverty traps.

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Even for the poor, there is a risk of creating poverty traps for those who rely on government-provided assistance for virtually all their necessities of life.

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She managed to find just over 40% of the original study group, and set about working out why some had stayed poor while others had flourished, and whether the favelas were the poverty traps that they seemed to be.

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The poverty that traps generations is concentrated in inner city neighbourhoods where communities have been failing for a generation or more.

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The tax package also tackled some of France's controversial poverty and welfare traps.

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But below 12 tonnes, it traps a farmer in poverty.

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For there are two well known problems with the way that the Census counts household income (and there are many of these sorts of traps in official US statistics: the pit that is the official poverty measure deserves a book all to itself).

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