"You're left with a situation where over short intervals his model looks good, but over long intervals it doesn't seem to work, " Fama says.

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I'm a big believer in short intervals of high intensity.

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Tian Tian and Yang Guang will be given the opportunity to meet up to three times for short 15 to 30 minute intervals, following the pattern of how pandas would come together briefly in the wild to mate.

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The pair will get the chance to meet up to three times for short 15 to 30-minute intervals, following the pattern of how pandas would come together in the wild to mate and then separate.

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It wasn't to be as we lost wickets at regular intervals, eventually falling some 27 runs short, but the scenes that followed were simply incredible and had to be seen to be believed.

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If the market is in a bear cycle, try dollar cost averaging (especially for larger portfolios), but keep the time frame relatively short, no more than three months, preferably in two week intervals between buys.

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Long intervals of pleasurably high income punctuated every now and then by a short, sharp shock.

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