I'm about to do something unfair.
Under no circumstances click on the following link unless you have two hours to kill and want to see an amazing takedown and analysis of the Star Wars prequels, during which you will alternately wince in horror and laugh uproariously depending on your own personal damage.
The Plinkett reviews (of which there are more—that's the second unfair thing I'll do today, tell you there are more of these) are one of my favorite guides to how movies, and stories in general, can go wrong. This also makes them a good resource for figuring out how to make stories go right.
About twenty minutes in, the reviewer analyzes characterization problems in Star Wars: Episode I compared to the original trilogy. He gives some friends a simple test—describe a given character from the original trilogy without using their name, physical description, or job. Then do the same for a character in the prequel trilogy. Han Solo, Obi Wan Kenobi, Luke Skywalker, Leia Organa, all prompt excited responses, and dead-on descriptions. When we get to the prequel trilogy, the interviewees umm and aaah all over the place.
When I first watched the Plinkett Review a couple years ago (yes, dear reader, I've watched these multiple times, and no, I'm not sure what that says about myself), that test stuck with me. Afterward, editing, I posed the question to myself: could I describe my characters without reference to their job, name, or appearance? We remember characters who pass—Han Solo, Ellen Ripley, Marian Ravenwood, Indiana Jones, Sherlock Holmes, Phillip Marlowe, Aerin Firehair, heck, even Humbert Humbert—while those who fail slip away into memory.
(Failing isn't necessarily a bad thing if your main character isn't the point of your story. The narrator of Kafka's Penal Colony doesn't pass this test. The Officer, though, does…)
Whatever you think of the Plinkett reviews as a whole, I think this test is useful for structural and character edits. What about you? How do you test your characters? What happens when one doesn't hold up?