Left-Wing Media Bias?

I have been following the science of determining (or disproving) the “left wing bias” of the media for a long time. I have seen lots and lots articles on the subject with many many charts and graphs in them. And they all basically look like the one here [PDF]. I’m linking to this one because it’s new and…if you’re following this whole “Lying Liar Political Scientist Published an Article with Lies” story, it has the benefit of being relevant to that discussion as well.

If you are following the whole LaCour fiaso read the whole thing. Basically, LaCour probably faked data on a 2nd article as well (and this essay is written by the guy that LaCour jocked the data from). If you’re only interested in the “media’s left wing bias” angle, then direct your gaze to page 5. What that chart is telling you is that, while there does seem to be an apparent “leftish slant” this is far from certain and could actually be flat wrong.

  1. Most of the studied channels appear to be inbetween the moderate left hump and non-partisan 0.
  2. There are two channels to the left of moderate left and no channels to the right of moderate right.

However, and this is critical, with the exception of Lou Dobbs’s show, all the confidence intervals (Bayesian credible intervals) overlap 0…which means they aren’t statistically different from “centrist”…and some of them could be “conservative.” Those CIs are huuuuuugggeeee. They basically run the entire gamut of the base dataset. I’ll also mention that most of the CIs (all but three) run most of their difference to the right. I think that’s difficult to interpret, but the consistency of this right skew across channels implies meaningfulness.

Some of this is a limitation to the types of methodologies available to this kind of research. But some of this is likely due to the fact that…well….most channels aren’t interested in 100% alienating 50% of their potential audience and thus…at the very least…attempt to appear neutral if not being, in fact, neutral. In the words of the author:

In the replication, only one show, Lou Dobbs Tonight, has a credible interval that does not overlap zero. Applying LaCour’s criterion, Lou Dobbs Tonight would be classified as “conservative news,” while all the remaining shows would be classified as “centrist news.