Suppose that the proportion of young adults who read at least one book per month is 0.15, and this proportion is the same in Bos
ton and New York. Suppose that samples of size 400 are randomly drawn from each city. The standard deviation for the sampling distribution of differences between the first sample proportion and the second sample proportion (used to calculate the z score) is _______.
The standard deviation for the sampling distribution of differences between the first sample proportion and the second sample proportion is given by :_
, where = First population proportion.
= Second population proportion
= First sample size
= Second sample size
As per given , we have
Then ,
Hence, the standard deviation for the sampling distribution of differences between the first sample proportion and the second sample proportion (used to calculate the z score) is <u>0.025</u> .