Ratings vs. grades


Over the years I’ve been accused a few times of favoring R-rated movies over squeaky-clean wholesome ones. This accusation is always from people who are upset that I have failed to enjoy some crappy (but clean!) movie or theatrical production, and it’s a charge that only takes about 10 seconds of browsing to disprove.

I posted a blog entry about the most recent incident, in which a fan of the mediocre (but clean!) “Suits on the Loose” said, “I imagine you are R-rated movies or nothing!” This prompted a faithful reader and EricDSnider.com message board regular named Matt to do some calculating, to determine what my average grades are for each rating.

Not surprisingly, he found little variance among the ratings. (The message board thread where he posted his findings is here.) But Reed Price, another reader and expert Excel user, wondered about the results and did some calculating of his own. He sent me the Excel spreadsheet with the results that I believe are conclusive.

Like Matt, he first translated my grades (A-, B+, etc.) into numbers. The system he used was as follows:

A = 4.000
A- = 3.666
B+ = 3.333
B = 3.000
B- = 2.666
C+ = 2.333
C = 2.000
C- = 1.666
D+ = 1.333
D = 1.000
D- = .666
F = 0.000

(Matt had used .700 and .400 instead of .666 and .333, which accounts for some of the variance in his and Reed’s findings. I think .666 and .333 make more mathematical sense.)

Then he applied those numbers to the 1,617 reviews on EricDSnider.com and came up with the averages grades for each rating:

G: 2.67 (B-)
PG: 2.40 (C+/B-)
PG-13: 2.30 (C+)
R: 2.61 (B-)
NC-17: 2.08 (C)
Not rated: 2.59 (B-)
All movies: 2.48 (C+/B-)

As you can see, G-rated movies actually get the highest average grade from me, though it’s neck-and-neck with the R-rated ones. But the difference between the highest (G) and lowest (NC-17) rating is only 0.59 — about two-thirds of a letter grade.

In other words, a film’s rating has no influence on how highly I rank it. It’s the movie’s merit as entertainment and art that matters. This is obvious to most people, of course, but it’s fun to have some math to back it up.