This article appears to make two underhanded assumptions to make its case, without giving sound justification for either.
1) "So is there a better way to judge a film's popularity?Yes: Use a per-theater average."
Therefore, a film that makes $20,000 in the one theater that runs it is more popular than a film that makes $10,000 per theater in 4,000 theaters? This presumes that if you showed the first film in 4,000 it would make twice as much money. I wouldn't presume it would make even close to the amount of money the second film made. Theater owners are mainly profit-seeking entities; if they thought that critically-acclaimed art-house films would make more money for them, they wouldn't throw money away to dedicate a few more screens to Spiderman 3.
Seriously, that 4,000-theater movie is probably shown in every small town in the country, where a $10,000 gross is not even possible. The art-house flick may be shown in one or two theaters only in the cities. What do you think the per theater average of Transformers would be if it got the latter type of distribution?
And yes, if you played the first film in 4,000 theaters, it would make more than $20,000 total. However, it would not gross $80,000,000 either - I'd bet that the total would likely be much, much close to the lower number.
2) "So what happens when we sort by overall per-screen average?"
That makes so little sense, it smells of intentional obfuscation. The only reason I can fathom for a film to play on multiple screens in the same theater is that it is so popular that the audience can't fit to see it one screen. Which is more popular: a) a film would overload one screen, but manages provide an 80% capacity crowd for multiple screens, or b) a film that provides a 90% capacity crowd for a single screen?
The only reason we could even consider the per theater number is that films playing in more theaters are accessible to more people and may appear more popular. However, films playing on multiple screens in the same theater are not more accessible, they're simply more popular. Yet, the author introduces the horrendously misleading per screen statistic as a measure of popularity, without giving any reason for it. It is simply not meaningful in this context.
So does the article prove its thesis: "Believe it or not, though, critically acclaimed films generally do
better than critically panned films at the box office—if you measure
their performance in the right way."? Only if the "right way" is the one that begs the question. The article proves that if you show a critically-acclaimed film in the small subset of theaters where such films make a lot of money, and limit them to one screen per theater, they'll make a lot of money per screen.
PS. To add insult to injury, this article makes at least one other claim without giving meaningful justification for it.
"I certainly accept the fact that America's overall cultural tastes have degraded. Serious films for adults, such as The Best Years of Our Lives, The Bridge on the River Kwai, The Graduate, and The Godfather, were all No. 1 box office hits for their respective years. So was Saving Private Ryan as recently as 1998. Seems an eternity ago. Now even our most critically acclaimed films are cartoons: Persepolis, Ratatouille, and The Simpsons Movie."
Even ignoring the gratuitous claim that animations cannot be adult movies, (The Simpsons Movie is not exactly targeted at five-year-olds) I can't see how the author has proven statistically that serious films now top the box office much less often. The four films he mentions span the period 1946 to 1998. If you look in the top 5 instead of top 1 of annual box office numbers, there are enough high-grossing adult films since 1998: The Passion of The Christ, The Sixth Sense, Cast Away, The Da Vinci Code, etc. (http://www.imdb.com/boxoffice/alltimegross). Even if it could be shown that "serious" adult films don't top the box office as much anymore (a hypothesis for which the article provides no real support), it could easily have occurred because movie studios have gotten better at using techonology (see Pixar) to draw new audiences to non-serious, non-adult films (e.g. kids), not because adult tastes have degerenerated.
In general, I expect Slate articles to provide more support for their arguments and not be gratuitously self-serving. In this case, I've seen Fray arguments using four-letter words that were better reasoned.