God is in every leaf of every tree, but he is not in every leaf of every parable.
Let me explain with a story. A few months ago I read the new book, Doing Data Science, by Rachel Schutt and Cathy O’Neil, and I came across the following motivation for comprehensive integration of data sources, a story that is reminiscent of the parables we sometimes see in business books:
By some estimates, one or two patients died per week in a certain smallish town because of the lack of information flow between the hospital’s emergency room and the nearby mental health clinic. In other words, if the records had been easier to match, they’d have been able to save more lives. On the other hand, if it had been easy to match records, other breaches of confidence might also have occurred. Of course it’s hard to know exactly how many lives are at stake, but it’s nontrivial.
We can assume we think privacy is a generally good thing. . . . But privacy takes lives too, as we see from this story of emergency room deaths.
This particular story, though, set off my Spidey-sense. As I wrote at the time:
One or two patients per week? 75 people [in a year] is a lot! To calibrate, I’d like to get a denominator, the total number of deaths each year.
I’m not sure how large the “smallish town” is. Here’s Wikipedia: “A town is a human settlement larger than a village but smaller than a city. The size definition for what constitutes a ‘town’ varies considerably in different parts of the world. . . . In the United States of America, the term “town” refers to an area of population distinct from others in some meaningful dimension, typically population or type of government. . . . In some instances, the term “town” refers to a small incorporated municipality of less than 10,000 people, while in others a town can be significantly larger. Some states do not use the term ‘town’ at all, while in others the term has no official meaning and is used informally to refer to a populated place, of any size, whether incorporated or unincorporated. . . .” Wikipedia then goes state by state, for example, “In Alabama, the legal use of the terms ‘town’ and ‘city’ are based on population. A municipality with a population of 2,000 or more is a city, while less than 2,000 is a town.”
Just to go forward on this, I’ll assume the “smallish town” has 10,000 people. If approximately 1/70 of the population is dying every year, that’s 140 deaths a year. So that can’t be right—there’s no way that half the deaths in this town are caused by poor record-keeping in a hospital. If the town had 20,000 people (which would seem to be near the upper limit of the population of a town that one would call “smallish,” at least in the United States), then we’re talking 1/4 of the deaths, which still seems way too large a proportion. Even if it is a town with lots of old people, so that much more than 1/70 of the population is dropping off each year, the numbers just don’t seem to add up. . . .
Based on my calculations, I feel like there is something missing in the story that was told about the hospital records. I could be wrong, though. I might be missing something subtle or even something obvious. It’s hard for me to know, though, because the story is not sourced.
OK, picky picky picky. So what’s my point?
My point is that, if we want to truly learn from a story, in the “God is in every leaf of every tree” sense, we can’t just relax and soak in the message, we need to push push push. I don’t know what’s going on here, whether the story is entirely made up or maybe the numbers got garbled and are off by one or two orders of magnitude or maybe two stories got mashed up and something was lost in translation, or maybe there’s some key aspect I’m not understanding. Rachel put me in touch with David Crawshaw, the source of this story, but he did not reply to my questions or maybe they did not reach him.
The point is, we’ve hit a brick wall. Without sourcing, without any way to get more information, we don’t have a story at all, we have a parable.
par·a·ble noun \ˈpa-rə-bəl\
: a short story that teaches a moral or spiritual lesson; especially : one of the stories told by Jesus Christ and recorded in the Bible . . .
specifically : a usually short fictitious story that illustrates a moral attitude or a religious principle
OK, so there’s nothing religious in this parable (nothing about Bayes or Emacs or Linux, yuk yuk yuk) but, yes, it illustrates a moral attitude. The key is that the story is simple and has just one purpose. The purpose is the moral. It’s not really considered desirable for a parable to have depth. If deeper investigation into the parable were to change or complexify its message, that would defeat the purpose.
I’m a statistician, and I like stories more than parables. I like that when I look into a story or a statistical example carefully, I can keep learning. I like the fractality of stories, the way that the deeper we look, the more we can learn (and this is the subject of one of my papers with Basbøll).
In telling this particular story, I’m not trying to beat up on Rachel, or Cathy, or David Crawshaw. Indeed, for the purpose of writing a general-interest book, maybe a parable works better than an endlessly-complexifying story. I have no idea. But I think it’s been a good real-life story to illustrate the distinction between parables and real-life stories. Originally I was hoping to find out from Crawshaw what was up with this hospital, but since he has not (yet) responded (which is fair enough; it’s hardly his job to respond to a question from someone he’s never met, regarding a parable he told that appeared in somebody else’s book), that’s part of the story too. If I do hear from him, I’ll post an addendum here.
P.S. Nobody seems to have heard from David Crawshaw on this but Cathy just informed me that she’s inserting a footnote in the second printing, pointing readers to this post so they can make their own judgments.