The random sample selection and different sample positions ensure the samples to be representative and fair.

计算机随机选择采样点，采样点车车不同，保证了样品的代表性、公正。

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For example, if an employer can demonstrate that a typing test and skills tests using Microsoft Office software products constitute a fair sample of the content of an administrative assistant job, then the tests will probably be considered content valid.

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To be fair, Hulbert does note that he was looking at a small sample size and that there have been instances where the CAPE ratio has stayed at high levels before a bear market set in.

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