The Professor's Response

For 14.4, problem 2: I think you got the wrong answer... p= .05 in the beginning, and you looked up .5 on the chart. Look out for this!

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Professor McGukian

Hi Demi,

You always use p = 0.50 on the binomial table when solving a sign test problem. The reason is that the claim is about the median for a population. The 0.50 comes from the fact that the median is the 50th percentile.

Also, the 0.05 in this problem is the significance level, which is denoted by alpha. It is not the value that you use when visiting the binomial table. The significance level is used to make your initial conclusion once the p-value has been calculated.

Professor McGuckian

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