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== 3.19#h(0.6em)Statistical Literacy


    #notebox("Note", rgb("#8a94a6"), rgb("#556666"), rgb("#f7f8fa"))[
#emph[Prerequisites]


      Median and Mean #linebreak() 
                 #linebreak()
]


    The Mean or the Median?


    The playbill for the Alley Theatre in Houston wants to appeal to advertisers. They reported the mean household income and the median age of theatergoers.


    
=== What do you think?


    What might have guided their choice of the mean or median?


    It is likely that they wanted to emphasize that theatergoers had high income but de-emphasize how old they are. The distributions of income and age of theatergoers probably have positive skew. Therefore the mean is probably higher than the median, which results in higher income and lower age than if the median household income and mean age had been presented.