Feeds:
Posts
Comments

Archive for the ‘Models’ Category

I apologize for the non-existent blogging the past few weeks.  I’ve been really busy with my new company.  I’m going to try blogging more short items rather than my trademark essays in the hope that reduced barrier to entry will result in more supply.

First up is a provocative post by the ever-interesting Scott Sumner.  Rafe in particular should read it because Sumner starts from one of Rafe’s favorite premisse that “laws” of nature are purely cognitive constructs.  We should measure them by their usefulness and not ascribe to them any independent existence. So Newton’s laws of motion are useful in certain contexts.  Einstein’s are useful in others.  But neither are ground truth.  Moreover, we will never find ground truth.  Just successively more accurate models.

Sumner uses this bit of philosophy to justify abolishing inflation, not, “…the phenomenon of inflation, but rather the concept of inflation.”  More specifically, price inflation. He explains why this concept is ill-defined and not only unnecessary, but confusing, for understanding the macroeconomy.  He asserts that we should expunge it from our models.  It doesn’t really exist anyway, so if models do better without it, we won’t miss it in the least.

Read Full Post »

This is not my meditation, it was created by Cellucidate:

(more…)

Read Full Post »

Heng, et al recently published a review paper that brings together and touches on many different aspects of cancer complexity.  I thought this an opportunity to selectively quote the paper and organize the quotes loosely around various complex systems concepts they relate to.  I’m curious whether this makes sense to readers of this blog, or whether there’s too much unexplained jargon and too many large conceptual leaps.  Please ask questions or make comments freely below.

One preface I think will help is to understand that genome, karyotype and chromosome refer roughly to the same thing.  Here are several schematics that I will present without explanation that together illustrate how genes relate to genome/karyotype/chromosome structure, and how that in turn relates to the so-called genetic network (loosely equivalent to the “proteome”).  Of course “gene” is an outdated and inaccurate concept, so don’t get too hung up looking for genes here, just understand that they are sub-structural elements of the genome.

From MSU website

Read Full Post »

Kevin just posted about a great article by Felix Salmon in Wired.  I underlined three quotes in my reading of it:

  1. “Correlation trading has spread through the psyche of the financial markets like a highly infectious thought virus.” (Tavakoli)
  2. “…the real danger was created not because any given trader adopted it but because every trader did. In financial markets, everybody doing the same thing is the classic recipe for a bubble and inevitable bust.” (Salmon)
  3. “Co-association between securities is not measurable using correlation…. Anything that relies on correlation is charlatanism.” (Taleb)

(more…)

Read Full Post »

I try not to practice false modesty (those of you who know me well probably just did a spit take at that understatement).  So while I try to stand up and admit when I’m wrong, I also like to stand up and point out where I’m right.

It shouldn’t be a surprise to any of you that I came to the conclusion that climate models are pretty much total bullshit. My problem with them is that they are incomplete, overfitted, and unproven.  It turns out that one of the foremost experts on forecasting in general also thinks that these models have no predictive value. In fact, items (6) and (7) of their statement shows that you can predict the future temperature really well simply by saying it will be the same as the current temperature.

You can read their more formal indictment of climate forecasting methods here.

Oh snap!

Read Full Post »

How Our Moral Compasses Fail Us

From the comments on my Introduction to this series, it appears I have discovered a controversial topic. Good. My first objective will be to illustrate why we cannot rely on  moral compasses to guide society. After some thought, I have decided to break the topic of moral compasses into two posts: how they fail and why they fail.

(more…)

Read Full Post »

I was recently having a conversation with a mutual friend of Rafe’s and mine.  Like the two of us, he’s quite smart, well educated, and socially aware.  I respect his thinking a lot. However, during the course of this conversation, it became clear to me that he holds what I think of as an overly moralistic view of human behavior.

From my perspective, it seemed like he thinks that people’s behavior is governed primarily by an internal moral compass rather than incentives. So if you want to change their behavior, you should redirect their moral compass rather than adjust their incentives. People who don’t adjust their behavior are defecting from society and should be sanctioned.

I encounter this view quite often in my social circle and this instance inspired me to write a series of posts to explain how I think things actually work.  You’re free to disagree with me, of course. In fact, I expect most people to disagree with me. But I’ve thought rather hard about this issue and I’ll put my model up against the moralistic view when it comes to predicting a population’s average behavior or choosing an effective policy prescription.

(more…)

Read Full Post »

Older Posts »