The handlers note where the scat is found and take a sample for analysis to determine if it is from a tiger and to check the animal's health.

VOA: standard.2010.02.22

You don't have to count all the leaves on the tree, you can take a sample and you count that and then you multiply.

你不必数树上所有的叶子,你可以抽样,然后计数,再相乘即可

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And the other thing you can do is take self reports like the ones you're doing, hopefully do enough of them, and a random enough sample of the population, that you can extrapolate from that sample to the whole population, and try to estimate what people are eating in that way.

还有其他可以做的,比如大家正在做的这种个体调查,希望能把它做的充分些,如果有充足的随机样本,就可以从样本推断出,整个总体,从而推断哪类人有这样的饮食习惯

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