A not so random sample would probably work just as well, such as that done by the Barnum and Bailey circus to their flock of elephants.

不是随机找的大象也行，因为Barnum和Bailey马戏团用他们的一群大象也做过类似实验。

youdao

Broadway actor Christopher Fitzgerald has been cast in the title role as PT Barnum, the legendary US showman who created the famous Barnum and Bailey's Circus.

BBC: Barnum musical to return at Chichester Festival Theatre

Barnum and Bailey established trend-setting practices like sending promoters by train, in advance to future circus sites to pass out flyers, set up billboards and even foster rumors of the incredible shows that were coming to town.

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