It can be misleading, even illusory, to cite an average statistic on the entire E.U. and U.S. when their respective member-states differ significantly in their own averages. To be sure, overall averages, such as pertain to an empire-scale union of states covering many subunits are useful in comparison with the overall average of another comparable union. Additionally, in cases in which the state averages do not differ much, the overall average for all of the states aggregated is not misleading. Abstractly, an average of numbers that ranges from 50 to 50,000 is less reflective of the facts on the ground than is an average of numbers that ranges from 50 to 60 because neither of these outliers is much different than, say, an average of 55. In contrast, especially if most of the data from 50 to 50,000 clusters around these poles, then to say that an average of 23,000 represents something actual is dubious and even misleading. It is also misleading to compare the average pertaining to one empire-scale union of states with the average of a state in another such union. Such a category mistake regarding scale and polity-types and levels is commonly made in comparing and contrasting the E.U. and U.S. In an effort to rectify the recurrent cognitive-ideological lapses bearing on trans-Atlantic comparisons and contrasts, a proper comparison of salary averages can serve as an illustration of how to compare “apples with apples, and oranges with oranges” in institutional political analysis that is comparative in application.
The full essay is at "Salary Averages in the E.U. and U.S."