At least two studies, one for the World Bank and the other for the Asian Development Bank, show that the effect is not significant.

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One thing NOAA's experts seem clear about is that the oil leak will not have a significant effect on the formation of the hurricanes themselves.

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Technically, column C should also account for the lag between stocks going ex-dividend and the dividend payment, but this should not significantly effect the calculations unless the dividend in question is a significant part of the change in your portfolio value on any given day.

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The effect is robust over time, economically significant, unlikely to be caused by data-mining, and not related to taking excess risk.

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The effect is robust over time, economically significant, unlikely to be caused by data-mining, and is not related to taking excessive risk.

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