Having a movie critic make the argument for "Why we need movie critics" is sort of like asking bathroom attendants why we need bathroom attendants or Canadians why we need Canada: You're kinda going to receive the most self-serving response ever. Leave it to Slate to ask the hard questions, then! Enter Erik Lundegaard, who, at least according to RottenTomatoes.com, has published some 96 movie reviews, though we suspect more. But not only is Lundegaard a staunch defender of his practice, he's good with math!

Lundegaard explains the benefit of film critics in this way: It's not that you necessarily have to agree with critics, or that they're going to like the most popular blockbuster movies, but critics actually do, on a whole, applaud the movies that turn out to be the highest-performing, and take craps on the movies that do the poorest. Coincidence, amazing forecasting, or cause-and-effect?

Here are the highest-grossing movies from 2007, along with each film's rating from Rotten Tomatoes, a Web site that quantifies critical opinion. (In the Rotten Tomatoes vernacular, films that garner positive reviews from at least 60 percent of critics are considered "fresh," while those below 60 percent are considered "rotten"):

You hardly need the Rotten Tomatoes rating. Four of the top five films are sequels; the fifth a sci-fi flick based upon a 20-year-old cartoon, which was itself based upon a toy. None is exactly Citizen Kane. Or even Jaws.

But here's something else they have in common: They were the only five films in 2007 to open in more than 4,000 theaters. Beyond the cause-and-effect question—do people see what studios make available and market, or do studios make available and market only what people want to see?—the popularity of a movie, via box office grosses, is to a great extent a self-fulfilling prophecy. So is there a better way to judge a film's popularity?

Yes: Use a per-theater average. Fred Claus, for example, made $18 million its opening weekend, which, out of 630 films released in 2007, is the 43rd best opening weekend. Not bad. Then you notice it opened in 3,603 theaters, giving it a per-theater average of $5,138. That ranks 246th. Not good. Fred Claus also got bad reviews: a 23 percent rating from Rotten Tomatoes. Call it a coincidence if you like.

And also:

The numbers are starkest with limited-release films (fewer than 2,000 screens). Art-house films that critics loved, such as Away From Her and The Diving Bell and the Butterfly, averaged $3,113 per screen, while arthouse films critics were iffy about, such as Interview and Margot at the Wedding, didn't even do half as well, averaging only $1,322 per screen. Some people are paying attention.

And in conclusion:

Percentagewise, the critic effect is less pronounced for the supposedly critic-proof blockbusters, but it's still there. On average, the "fresh" blockbusters, such as Harry Potter and I Am Legend outperform the "rotten" blockbusters, such as Wild Hogs and Bee Movie, by more than $500 per screen. Almost any way you slice it, if a majority of critics like a movie, chances are it will do better at the box office than a similar film the majority of critics don't like. Far from being elitist, movie critics are actually a pretty good barometer of popular taste.

[Slate]