Quotes

"The Way of a Warrior is to establish harmony." ~ Morihei Ueshiba O'Sensei, Founder of Aikido

Wednesday, May 1, 2013

Pseudologic of Genetic Predictions

An acquaintance of mine just wrote an interesting piece titled It’s Time to Stop Pouring Research Money Down the Genetic Sinkhole which alludes to an undeserved faith people have in the predictive power of genetics.
Although autism is becoming more widely understood as a neural difference, not a “psychiatric disorder,” it is one of the profiles that is subject to this intense witch hunt. In his article [Five Decades of Gene Finding Failures in Psychiatry], [Jay Joseph] mentions autism in passing, as an example of one of the many areas where genetic research has been a failure.
[...]
But the problem is larger than that. Science understands (if one can even be so generous as to use that word) a very tiny fraction of the human genome. Most research to date has focused on the 1% or so of DNA that codes for proteins (i.e. has the genetic instructions for making the proteins that constitute the human body). The other 99% remains pretty much a complete mystery, although progress is starting to be made in analyzing that. The ENCODE project (ENCyclopedia Of DNA Elements) is still very much in its infancy.
Conditions (defined by behavioral observation) may correlate with certain genetic markers, but if we only observe the genetic markers how well does it predict these other conditions?
The fact is science is not a perfectly deterministic system.  Randomness and uncertainty affect all observations/measurements.  As such, we are stuck dealing with conditional probabilities.  Trying to exactly equate these logical propositions is inherently flawed and likely to fall victim to the Base Rate Fallacy.


(found this on Facebook)


Basically you are looking at the overlap of the events, e.g. Pr(moon & chicken) or Pr(autism etc. & genetics), and the proportion of that joint probability to that of the single event you condition upon; whatever serves as the predictor.

Few people have been to the moon so that is a rare event that greatly overlaps (or is encompassed by) chicken-eating.  Flipping it around (via Bayes' Theorem) we see a ton of people have eaten chicken but only a tiny few have ever been to the moon, therefore chicken-eating is not a good predictor.

For those who are more mathematically inclined:
Pr(A|B) "probability of observing A, given B has occurred or is known"


Genetic researches must assess the prevalence of these so-called markers in the general population.  Otherwise the strength/validity of the observed associations is highly suspect.

Taken to an extreme, we see the dystopian future depicted in the film GATTACA (one of my favorites).  Everything is the product of extreme eugenics engineering.  Anyone conceived in the old-fashioned way is an "Invalid."  I find this scene very poignant where this detective is speaking to the director about exceeding potential:


(At 1:25)
"No one exceeds his potential"
"If he did?"
"It would simply mean we did not accurately gauge his potential in the first place."
This big admission of their methods' fallibility really struck me.  You can never absolutely gauge potential. It's impossible. Measurement is an inherently flawed process. In my line of study, we try to design measurements/tests that are reliable but we have to account for the uncertainty from random error. We try to increase reliability by minimizing error but no measurement is perfect as that would require infinite precision.  If someone's job or life is at stake, you better have some strong evidence. The people in Gattaca were overconfident in the scope of their measurements and ignored the inherent limits of the information.

Even Edward Thorndike, one of the pioneers of psychological measurement, acknowledged that such tests are imperfect and were never meant to be an absolute prediction of your station in life (unlike his contemporary Lewis Terman):
"On the other hand to assume that we have measured some general power which resides in him and determines his ability in every variety of intellectual task in its entirety is to fly directly in the face of all that is known about the organization of intellect." (p. 126)
Thorndike, Edward L. (1921). Intelligence and its measurement: A symposium--I. Journal of Educational Psychology, 12(3), 124-127. [pdf]

Saturday, April 27, 2013

All autists are equal, but some are more equal than others

I'm becoming increasingly disillusioned with the so-called Autism Community.  It started last year when I wrote in this blog a post that got a ton of backlash.  I felt discouraged from writing since then.  Many of the readers/commenters grossly misinterpreted my ideas.  They thought I was advocating being passive in the face of abuse when actually I was talking about the need to be mindful of our speech/actions so that we are not contributing to the number of enemies and negative public perception.  For an analogy, imagine fighting a raging fire.  You must be able to contain or slow its spread.  If it grows larger, faster than you can gather/apply water you will never put it out.  That is a mathematical certainty. 

I think there is this notion that autistics are pure, innocent victims of unjust persecution so any hint of blame is seen as outrageous.  While it’s not exactly a war of our own making, it’s worth pointing out the part we can play towards breeding and prolonging conflict.  You can’t advocate for being viewed as comptetent/intelligent but ignore accountability.

I have seen a quite a bit of vitriol, rhetoric, and venom spewed forth by my peers.  That is what I wanted to caution against when I wrote Don’t Make Enemies.  Ironically, that is just what happened in the ensuing “discussions.”  Lydia Brown (author of Autistic Hoya), remarked:
Today, I am very disappointed in many of my friends and in myself.
I posted a link on Friday to a blog post by a friend, which at first generated mostly thoughtful and interesting discussion about its content. The discussion rapidly devolved over the last two days into name-calling, swearing […] and finally, actual physical threats […]
Almost every single person who participated in the "discussion" is Autistic. (I can only think of one person who wasn't offhand.) This saddens me, because while I personally took great issue with many of the things that were written in the original blog post to which I had linked, this fact more than proved many of the observations that its author made about vitriolic rhetoric. The world is watching us, and if all the world sees is that Autistic people are incapable of mature, calm, and respectful dialogue (and respectful doesn't have to mean "polite" or "denying problems exist" or talking to people who actually want to hurt you) amongst ourselves, never mind with the public, then we will NEVER be listened to and our ideas will NEVER be taken seriously.
April 15 at 4:07pm
And yet I was met with accusations of being the "tone police”, engaging in lateral oppression, and unfairly derailing arguments.  First off, lateral oppression is an absurd notion since if we're truly peers, by definition I don't have any power or authority over you.  Of course an argument should be judged by its merits (e.g. coherence) but there are tons of logical fallacies and possible errors in reasoning.  Pointing them out is necessary in debate/discourse.  However I’ve noticed many instances of someone crying 'derail!' as merely a plea to ignore the faults in their arguments and drop the counterargument(s).  Ironically, that would be an actual derail.

I get the sense that arguments that don’t toe the party line are taboo.  It's a slippery slope from dissent to thought-crime if we arbitrarily judge who is a REAL autistic advocate and what they *should* say.


This idea of an Autism Community is a farce.  It’s about as united as the United States.  What we have is a bunch of people who are angry (somewhat justly), highly opinionated, thin-skinned, and hegemonic.  Chained together by a common label “autism” but pulling in different directions and bickering about where to go and what to do.  Except, there is no one right direction.  It’s erroneous because while the symptoms may appear to be superficially similar, in all likelihood these are different underlying conditions with varying challenges and needs that are not being met by perpetuating a false equivalence.