Think about when the CTA comes up as a topic of conversation, or, if you're a Twitter user, when you take to your smartphone to mention our transit system.

OK, got it? Turns out you're not alone:

"The most interesting thing we found is that transit riders do not give any positive sentiment at a particular time. They only give negative sentiment," he said. Now, this may seem depressing if you work for one of these agencies. "But that’s not very disappointing," Hasan said, "because we found that the lack of negative sentiment is basically what transit authorities should look for. If there’s no negative sentiment at any given time, that means that things are running smoothly."

That's from Emily Badger, reporting from a "riveted room" at the Transportation Research Board's annual meeting. I'm not exactly sure what was riveting about it—it's basically my experience as a decade-long rider of transportation and a user of Twitter for several years. (Which is not a critique of the scientists, since I'm always happy to have someone do science to show that the world is basically what I think it is.)

Badger suggests that this sort of research makes a good alternative to focus groups through "sentiment analysis," the way pols and movie studios do:

What if, instead of politely asking people if they find their morning commutes safe, sanitary and efficient, agencies tapped into the raw and unscripted assessments we all love to broadcast from our smart phones?

I dunno—I don't find that people have much to say about public transit (except when it explicitly fails) until you start asking them good questions. Everyone watches movies, and most people pay attention to a handful of prominent politicians at any given time, so there's a good basis for comparison. On the other hand, most people don't have much of a basis for comparison when it comes to public transportation unless they travel or move around a lot. And there are the usual issues with specific media like Twitter versus demographics.

Alternately, I could see some synthesis of focus groups and instant mobile reaction—like a moving, real-time focus group to monitor sentiment at places and times on different parts of the system. Twitter grabs what we know; perhaps it, or some similar technology, could be pressed further to what we don't realize.

Photograph: AntoniO BovinO (CC by 2.0)