## Bayes fixes small n, doesn’t it?

What is a methods-careful practitioner to do when the number of observations ($n$) is small?  I don’t know how many times I’ve been told by a well-meaning Bayesian some variation of

Bayesian estimation addresses the “small $n$ problem”

This is right and wrong. Continue reading ‘Bayes fixes small n, doesn’t it?’ »

## Truth and Choices: Computational v. Analytical formal models

How do we show a statement about politics is true? Analytic formal modelers suggest one way:

## We all carry the scars

I served in the US Navy for a few months in 1986, five years in the early 90s, and another year and a half in the reserves. I was never asked to shoot someone. I never pulled a trigger when the weapon was aimed at a person. I served during, but not “in” the first Gulf War. I served during “peacetime”, or at least that’s how I thought about it. However, over the last few months I have been thinking more about my time in uniform, realizing the lasting and deep effects that experience had on me. Continue reading ‘We all carry the scars’ »

## Change of Intuition about the Definition of Insanity

My dad and I went to the recent Brown/Whitman California gubernatorial debate here at UC Davis. It was fun seeing “democracy” live and up close. One of the candidates twice repeated an old saw:

One definition of insanity is doing the same thing over and over and expecting different results.

## Dimensionality matters: three implications of ideology being multidimensional

Left or right? Liberal or conservative? Blue or red?  We know the terms bandied about in the punditverse, but it’s easy to forget that there is more than one way to divide the world into two political ideologies.

## The better the question, the worse the answer

Justin Wolfers wrote recently about the level of interaction between economics and other social sciences.  In particular, he wonders why economic work is not well represented in a list of the books most cited in social science research.  It’s a good question: I find many of the tools and techniques developed by economists are useful in my works studying political phenomena, and I do cite economic research.

One particularly thoughtful commenter on Wolfers’ post notes that economics combines the controversy of addressing everyday issues with the general inaccessibility of chemistry.  This conflict may make some people resist the conclusions of economists, ie. strong prior + incomprehensible evidence = small amount of updating.

## You’re Asking the Wrong Question, Fortunately

Today I got up, finishing a decision I started last night about how much to sleep before today.  I will choose my attire to fit the weather and strike the right tone in the classes I will teach. I will go to work and spend the day at work making optimal decisions about how to allocate my time and effort considering my immediate goals, teaching effectively and  preparing for an experiment, and longer term goals like getting along with my peers and building my tenure packet.  I will come home along a route that balances safety, convenience, fuel economy, and curiosity.  I will talk with my wife, play with my daughter, read to my son, all with an eye toward building both their individual lives and my relationships with them.  I may make a few allocation decisions about improving our house or saving for retirement.  I will decide whether to work out tomorrow morning, then  begin the decision about how much to sleep before tomorrow.

## All Theorists are Normative (or run that risk)

A recent exchange at the excellent Cheap Talk focused on how the uselessness of the United States’ recent promise not to nuke other states who comply with the Nuclear Non-Proliferation Treaty (NPT).

## Figuring significance significant figures

I recently sat through some great grad student presentations. Most of those presenting empirical results made a common mistake: they kept way too many digits in their presented results.  There are two problems with showing more digits than necessary:  false certainty and lack of clarity.  The extra certainty is certainly false because we know how accurate the estimated coefficients are:  that’s exactly what the standard errors tell us! Extra digits reduce clarity by cluttering up an already hard-to-read table with extra, unnecessary information.

Continue reading ‘Figuring significance significant figures’ »

## Computational modeling is not: simulation

Computational modeling and simulation have many similar things in common. They both involve using computers, they both use encoded descriptions of how things work, they both “run” one or (usually) many times.  The easiest way to see how they differ is to note their very different goals.