"In 2011, a group of researchers conducted（指挥） a scientific（科学(上)的） study to find an impossible result that listening to certain songs can make you younger. Their study involved real people, truthfully reported data, and commonplace（常见的） statistical（统计的） analyses（分析）. So how did they do it? The answer lies（躺） in a statistical（统计的） method scientists often use to try to figure（ 认为） out whether their results mean something or if they're random noise. In fact, the whole point（指向） of the music study was to point（指向） out ways this method can be misused（ 滥用）. A famous thought experiment explains the method. There are eight cups of tea, four with the milk added first and four with the tea added first.

  A participant（参与者） must determine（决定） which are which according（使一致） to taste. There are 70 different ways the cups can be sorted（整理） into two groups of four, and only one is correct. So, can she taste the difference? That's our research question. To analyze her choices, we define（给…下定义） what's called a null（无效的） hypothesis（假设） that she can't distinguish the teas. If she can't distinguish（区别） the teas, she'll still get the right answer one in 70 times by chance.

  One in 70 is roughly（粗糙地） .014. That single number is called a p-value（价值）. In many fields, a p-value of .05 or below is considered statistically significant（重大的）, meaning there's enough evidence to reject（拒绝） the null（无效的） hypothesis（假设）. Based（以…作基础） on a p-value（价值） of .014, they'd rule（统治） out the null（无效的） hypothesis（假设） that she can't distinguish（区别） the teas.