The "boomy" theory is that when times are good, we get overconfident and spend freely, then retreat into a risk-averse shell when times get tough.

“牛气哄哄型”理论认为，当形势大好时，我们会过于自信，花起钱来大手大脚，而当形势变得艰难时，我们就会缩进厌恶风险的壳里。

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Similarly, when a shopper goes to the store and listens to different sets of stereo speakers, she may notice that the ugly, boxy speakers have a less boomy bass and a roomier midrange than the small, sleek ones do.

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