Archive for July, 2015

On Evidence-Based Sentencing and the Variables of Race, Age, and Social Achievement

Saturday, July 25th, 2015

I was reading a paper on evidence-based sentencing called “Risk in Sentencing: Constitutionally-Suspect Variables and Evidence-Based Sentencing“. And in it, the authors list (list is generated by another study), fifteen different variables with statistically significant relationships with recidivism. Here are some (on a 0.30 scale):

  • Criminal companions: z=0.21
  • Antisocial personality: z=0.18
  • Adult criminal history: z=0.17
  • Family rearing practices: z=0.14
  • Social achievement (education, marital status, employment): z=0.13
  • Race: z=0.17
  • Age: z=0.11
  • Gender: z=0.06
  • Socio-economic status of origin: z=0.05

Immediate things that pop out: race, criminal companions (who you hang out with), social achievements (education, marital status, employment), age, gender, and socio-economic status of origin. According to this study, these factors indicate some probability of recidivism. Luckily, several of these variables (such as race and age) are constitutionally barred from being taken into account in sentencing decisions. But the point I want to make is that I don’t think most of these should be a factor in determining a person’s sentence. And I think this study is a great example of why we should be careful when drawing conclusions from analyzing data. I sometimes tell this joke: “100% of divorces are caused by marriage”. It’s silly, but I think it’s relevant here. Yes, divorces begin with marriage, but if you blame marriage on divorce, you’re kind of missing some important underlying cause. Sure, young poor uneducated black people who hang out with other criminals might have an increased chance of recidivism, but is that really the underlying cause? Is it really their fault that they are young, poor, uneducated and black living in a neighborhood where everyone else is young, poor, uneducated, and black?

This is a great example of algorithms just pointing out the obvious and yet missing the larger picture. It’s like Google’s flu detector which actually might only be a winter detector. We need to think about how we construct these algorithms and how we are employing them to make decisions that might affect hundreds of thousands of people. We shouldn’t be asking “how does the race variable relate to recidivism?” There’s nothing “variable” about race. Or age. Or socio-economic status. These are the wrong questions. Instead, why don’t we ask ourselves “What can we do, to improve a person’s life, such that the color of their skin doesn’t correlate with a high recidivism rate?” I think that’s a more worthwhile pursuit.


Book: World Dynamics

Saturday, July 4th, 2015

I like books. I am not a fast reader. I have not read thousands of books. I don’t even read all the books I own. But I like them nonetheless. I especially like collecting early editions of books that have a special meaning to me or that tried to predict the future, or books that were influential especially in design and technology and how those two fields would or could transform society.

Following Rune Madsen’s lead, I decided to write every now and then about the books I’ve collected. The first one is “World Dynamics” from Jay W. Forrester:

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Forrester was the founder of system dynamics. Unlike the dynamic systems class you might’ve taken in college were you draw bond graphs and model a box-sliding-down-a-ramp-on-a-spring-on-a-damper-on-a-pully-on-a-water-pump-on-a-generator-on-a-moving-train using a system of equations, Forrester’s system dynamics was meant to model complex problems like population growth, use and exhaustion of resources, industrial processes, or determining the success and failures of corporations (the original intent). “World Dynamics” is an application of system dynamics to model the world’s population growth and the exhaustion of resources.

Idea for the study supposedly originated when Forrester met with the founder of Club of Rome, a think-tank that deals with a variety of international issues. Back in the 60’s and early 70’s people had begun to think about the environment, the fear of overpopulation and the exhaustion of resources. This book was meant to give a prediction of what the world could look like in the future. Another book that came out of the Club of Rome was “The Limits to Growth” by Donella Meadows (still trying to get my hands on that one).

The model Forrester produced, predicted that the limiting factor in bringing the world into equilibrium would not only be population growth and the availability of food, but also pollution, crowding, and depletion of resources. Industrialization might be a bigger threat than overpopulation because of the limits of the environment.

The goal of producing the model was to search for an equilibrium where we could sustainably live with earth’s renewable resources. In the search for equilibrium Forrester suggests cutting food production to reduce the population. I’m not sure how exactly he envisioned this playing out, but it seems he was depending on a reduction in birth rates.

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Slightly less complicated than the Afghanistan plan.

This book is one of a long list of books and research that relied heavily on the hope that system dynamics could potentially solve the world’s problems. The idea back then was that if we had all the variables, and we understood how all of them behaved, we might be able to model just about anything, including, literally, the entire world.

And yet, here we are. Still unable to solve the world’s problems, having long abandoned the idea that we can model the world simply by coming up with the right equations.