A snowball sampling non-probability sample was used.

样本的取样方式采取 非机率型之滚雪球抽样法。

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Because of the phenomenon that the negative self-scattering cross sections cause the negative probability sample, a nonnegative corrected method is put forward and validated by the benchmark problems.

针对输运修正引起的自散射截面导致的负概率抽样现象，提出了一种非负修正方法，并用基准计算验证了该方法的正确性。

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Experiments, Outcomes, Sample Spaces, Events, Probability, Axioms of Probability.

试验，结果，样本空间，事件，机率，机率公理。

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This online survey is not based on a probability sample and therefore no estimate of theoretical sampling error can be calculated.

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The monthly Consumer Confidence Survey, based on a probability-design random sample, is conducted for The Conference Board by Nielsen.

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Therefore, the convention among academic researchers is that it is ok, and you can claim your conclusion based on only a sample of observations, as long as the probability that you are wrong is no bigger than 5%.

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