Mighty brave, zolltan, being in favour of something everyone agrees about anyway

How is discrimination unlike this PID controller? Let me count the ways.

I was reading this article (thanks to A.) about a transgendered man’s thoughts on getting into science as a girl, and I noticed that a lot of the examples were from things that happened way before she became a researcher – in high school, etc. Meanwhile, a couple weekends ago, Zuuko and I were listening to a Louis CK monologue where he talked about blacks and whites in America and he pointed out that any old black person you see probably remembers segregation. I think this is a strongly underappreciated point when talking about discrimination: what happens early in people’s lives matters, and people live for a long time. There are people working in science today that came from a cohort that was choosing their careers in the 50’s and 60’s. Of course discrimination played a role in those choices! For the specific example of women in science, you don’t need to go nearly that far back to get to the time when flagrant discrimination was out in the open. Close to home, a certain Nobel prizewinning ex-member of our faculty apparently frequently claimed that women can’t and shouldn’t do physics. And he didn’t retire until 2002.

And I just thought of a metaphor for talking about this, so please indulge me. There is such a thing in electronics called a PID feedback circuit. The way it works is easiest to understand with the example of a thermostat. Say you have a “set” temperature and the actual temperature of your room. The P (proportional) feedback checks how different your “set” temperature is from the actual and heats up or cools down the room in proportion to this difference. However, when the difference is small, the action taken is proportionally small, thus just P-feedback has the problem of only reaching your “set” target asymptotically slowly. Thus there is an additional control circuit called I (integral) feedback. This keeps track of the difference between the “set” and actual value for some amount of time, and then heats up or cools down the room based on the overall difference. That way, if your room used to be way too cold and is now just slightly too cold, it will still get heated up some. However, now this system is prone to overshooting and continuing to heat up your room past where it’s warm enough. That’s where the D (differential) feedback comes in. It looks at the trend, and acts to counteract the trend. One thing to note here is that while a PID circuit is a great invention, the treatment of problems in real life rarely follows this algorithm.

Another thing to note is that the “D” circuit is fast to respond, because it just need to take two measurements and see their difference. The “I” circuit is slow because it needs to take data overa long time, all the while comparing that data to the desired setpoint. The connection to discrimination is this: it used to exist. It still exists (but it used to, too). However, in our society, it is much less prevalent and socially acceptable than it used to be. The “trend” is clearly against discrimination of most kinds. This is what people notice when they complain from a position of traditional privilege that “political correctness has gone mad” or that you need to fight for “men’s rights” or that Christians are a persecuted minority in the U.S., etc. etc. But they are forgetting to think of the “proportional” and “cumulative” effects.

This entry was posted in politics, science. Bookmark the permalink.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s