Friday, April 1, 2011

A little more on stable relations in the social sciences

You all are never going to believe that I'm going to quit blogging if after every time I suggest I will I post three new posts... oh well...

Gene Callahan links to my discussion of the shifting unemployment-investment curve that John Taylor posted, and points out that this is true of the social sciences in general. We are capable of identifying meaningful relationships - even meaningful causal relationships. But the parameters of those relationships, because we're dealing with such a complex system, tend to shift. That means we have a real phenomenon but our observation of it is a little different over time. OK, big deal. That is the nature of the social sciences and any science of a complex system. Gene talks specifically about Zipf's law, a neat little regularity that is near and dear to my own heart.

While we're still on Taylor's post, I want to point out a good response from Noahpinion that essentially makes all the points I have made over the last couple days (this isn't surprising at all, everyone should know this, the curves shift over time, etc.).


  1. Kind of, but no. I think stable relations get absorbed into definitions and equations, and we cease to consider them independent phenomena, but rather separate manifestations of the same process.

    It seems to me this happens a lot with words and concepts in science. For example, suppose a new disease is discovered. At first, the disease is is identified by a set symptoms. Then these symptoms are observed to occur in people who carry a particular virus. Once the general relation is established the disease is gradually defined by its effects, i.e. the symptoms. Soon the relation becomes tautological, a trivial logical consequence of what it means to be that disease. What was once a stable relation between two distinct phenomena become a single thing.

    I haven't thought this through very well, but something like this seems to be going on.

  2. I'm not sure what the "but no" is in reference to exactly.

    One of the things I mentioned in the earlier post was that nobody at all should be surprised by this nice curve. We all should know it very well. Now, its EXPLANATION is a much trickier matter (ie - how we would tie the symptoms to the virus in your example). I acknowledge that is a very tough problem in a lot of cases (including this one). I would talk about the source of this relation in a very different way than, say, Mattheus would.

    Does that make sense? Or are we talking about something different.

  3. Maybe we're talking about something a little different.

  4. "That is the nature of the social sciences and any science of a complex system"
    So true. Nothin' but love for complexity theory.


All anonymous comments will be deleted. Consistent pseudonyms are fine.