Sunday, July 05, 2009

The Drunkard's Walk

My poor blog has been neglected lately. Not because I haven’t had any good ideas to post about, but simply because I haven’t had the time to slow down long enough to type them up. I’ll get things back on track with a few book reviews.
Humans have what seems to be a pathological inability to comprehend statistics. We tend to think things are freak occurrences but, when you analyze the probability we see that they are actually quite ordinary. We interpret it as some kind of an omen when a stain on the wall of the burn pattern in a piece of French toast appears to vaguely look like you deity of choice. Yet how many pieces of toast have you had that didn’t look like that and why do you think that they would choose this way to manifest themselves?
In The Drunkard’s Walk: How Randomness Rules Our Lives Leonard Mlodinow explores exactly these issues. The book starts out with a very intriguing history of the study of statistics. If for this history alone the book would have been well worth the read. But Mlodinow makes the history much deeper by exploring the many ways in which we misunderstand statistics and what it means for something to be truly random.
I’ll share a short story form the book that illustrates how humans are very poor judges of what it means to be random. Several years ago when Apple first came out with their iPod they had a cool feature that would randomly pick the next song rather than play the list in order. Neat huh? Well they started to get complaints. Sometimes the feature would play songs from the same artist consecutively. And sometimes they would repeat the same song with only a song or two between playing. Occasionally it would even play the same song back to back. This lead people to believe that their randomizer function wasn’t working properly. After a bunch of complaints they changed the algorithms. They’ve inserted code that won’t allow the player to play songs from the same artist consecutively. It also makes sure that the same song is not replayed for quite some time. What I find really funny about this whole process is that in order to make the order of the songs seem more random they actually had to make it significantly less random. Apple had to go out of their way to create a pattern that was NOT truly random because humans thought that the truly random shuffler was flawed.
This is just one example of the many ways that we fail to grasp statistics and how randomness affects our lives. I found this book very entertaining and eye opening.


  1. Thanks for the review. I haven't read the book, but it does look like something that would interest me. If you haven't read it, you should check out Freakonomics by Steven D. Levitt and Stephen J. Dubner.

    One of the problems that I had with Apple when the whole "random" debacle came to light, wasn't that the shuffles were random, it's that they hid behind the term "random" instead of acknowledging they weren't offering customers what they wanted. Yes it was random, or as random as an computer algorithm can be. But most people didn't want their music played in a truly random order. They wanted it played like their own private radio station. Many music players (both hardware and software) already had options for customizing the shuffle functions to not repeat songs until all songs had played, or to not play the same artist or title back to back. Apple finally added these features, never acknowledging that they got to hung up on being technically correct, that they forget to take into account what their customers actually wanted.

  2. GA Peach1:36 PM

    Good review, looks like an interesting read. If you haven't read it already, you might be interested in Taleb's book "The Black Swan: the Impact of the Highly Improbable"

  3. Thanks. I'll check it out.