HOW OTHERS SEE US. Villainous Company reads a Reason Foundation working paper, reprinting work in Journal of Labor Research, suggesting that moderate drinking augments human capital, leading to higher earnings.

The survey question on alcohol asks respondents, “Do you ever have occasion to use any alcoholic beverages such as liquor, wine, or beer, or are you a total abstainer?” From this question we create a dummy variable where drinkers have a one and abstainers have a zero. The survey also asks respondents the frequency with which they go to a bar or tavern. Choices include the following: almost every day, once or twice a week, several times per month, about once per month, several times a year, about once a year, never, and don’t know. From this question we create a variable indicating whether an individual frequents a bar or tavern at least once per month. This somewhat crude measure attempts to capture whether one drinks in social or nonsocial settings.

We therefore estimate the following equation:

Yi = ?Xi+ ?Ai + ?Bi + ?I , (1)

[THUD]

...where Y is the log of real earned income by individual i; X is a vector of personal and demographic characteristics; A is the drinking dummy variable; and B is the social vs. nonsocial drinking dummy variable.

A commenter grumbles that it's "sloppy econometrics."

The excerpt continues

Control variables in X include race, age, age squared, religion, schooling, marital status, parental education, number of siblings, and region of residence.

*sigh*

I'm inclined to agree. In many cases these "control" variables give the response functions different intercepts but the same slope: there is no way of establishing whether a Protestant who bar-hops (an interaction term) would do better than an agnostic who is a regular at some bar.