Because authority is at least partially determined by subjective judgement. A secular humanist PhD in Women’s Studies and Public Health will likely evaluate WWB’s authority differently from, for instance, Pat Robertson.

If you were to add a number representing human judgement to the algorithm, you’d need to have a LOT of faith in the person(s) assigning that number.

Hmm, I must say that’s something I hadn’t considered.

Still, I’m not ready to give up on the idea just yet. Wouldn’t adding a human element make such an algorithm possible? [It took me all of 5 minutes to go to the WWB (my first visit there) and figure out its "authority" level.]

But the key question isn’t how to design an algorithm capable of discerning authority because such a thing isn’t possible.

The key questions (imho) are (1) whether ANY algorithmic analysis can produce a useful result and (2)if users can commony grasp a nuanced understanding of how such algorithms work and stop confusing terms like “top”, “best”, “most respected”, “most reliable” and “most popular.”

But as Rachel pointed out (see her comment from August 13th), this isn’t a new problem, just a new-media version of an old one.

A quick example from the
MedGadget.nl list:

Well Woman Blog is ranked #62 while The Blog That Ate Manhattan is #77. The problem? Here’s an actual line from a WWB post: “A variety of [birth control] pills are available as well as injections and patches. None have proven safe for a woman to use.”

That last statement alone should disqualify WWB from inclusion in any medblogger ranking. Of course, the key question is how do you design an algorithm capable of distinguishing authoritative content from nonsense?

1. Polls and surveys are problematic because participants are self-selecting. Besides, I think we can estimate popularity without them.

2. Rather than endorsing external medical blogs, I think professional institutions like the AMA or BMA will probably create their own blogs.