Is core metrics definition truly bottom-up?

核心矩阵定义真的是自底向上的吗？

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The definition of a dragnet is a net that is pulled along the bottom of a river or lake to bring up anything that may lie there.

拖网的定义是一张网沿著河底或湖底拖拉，以起可能停留在那里的任何东西。

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Interest rates are the definition of rock-bottom low, but to paraphrase a wise man (whose name rhymes with Milton Friedman), interest rates alone say nothing about whether central bank policy is hawkish or dovish.

FORBES: The Fed Feeding a Bubble?

Do that and the definition pops up at the bottom of the page.

ENGADGET: Sony Reader PRS-T2 review: same old e-reader, new and (mostly) improved design

Worse, using the high-definition wide-screen mode puts black bars at the top and bottom of the viewfinder, reducing the effective pixel count by 25%.

FORBES: Magazine Article