I just finished Malcolm Gladwell’s Blink. Here’s a few notes.


The Blink thesis can be summarised thus:

  • Split-second decisions can be far more accurate than drawn-out, deliberate, “rational”, decisions.
  • However, split-second decisions can also be heavily flawed.
  • Interventions can be made to help people harness the power of split-second decisions. </b>

Evidence of split-second decisions over deliberate decisions

  • Experiment subjects quickly started following the profitable strategy in a card game, but could not explain why until much later.
  • The running example in Blink is an art artifact which immediately made art experts suspicious, but had been deemed authentic by the deliberate legal tracking process. The Greek sculpture turned out to be a fake.
  • A singer’s talent stunned veterans of the music industry and wowed audiences, but formal audience surveys ruled him commercially inviable. Keenna turned into a big success.
  • A military simulation pitted the Blue Team, USA, against the Red Team, a rogue dictator. The Blue Team used sophisticated decision-making processes and frequent explicit communication, whereas the Red Team communicated little and relied on the intelligence of individual units. The Red Team won.

Evidence of flaws in split-second decision-making.

  • A study inferred that car salespeople judged women and blacks to be less savvy, even when all actors were attributed with the same income and professions.
  • Warren Harding ascended to American presidency on the basis of one key attribute: he looked “presidential”.
  • Doctors possessed charts of current heart activity, but their diagnoses were heavily influenced by demographic factors which were largely gratuitous in light of the charts.

Strategies to improve snap-decision making

  • Practice, practice, practice. “Expert judgment” goes hand-in-hand with “snap judgment”. Many of the benefits of quick judgments are

  • Use technology to break the instant down. Many examples involve analysing videotapes. A tennis coach works with biomechanical experts to analyse serving actions. A “mind-reader” observes muscle movements as people talk. A marriage expert dissects a conversation between couples. In some cases, this knowledge can be captured and reused in real-time. In other cases, it is simply an example of extracting big information from little moments.

  • Make first impressions count.An art director explains how he asks staff to cover items, so they can be revealed at once when his entire focus is on it. Or they will place it somewhere surprising like a wardrobe, so he’ll have the full benefit of capturing his first impressions.

  • Concentrate on the factors that matter. A care salesman does plenty of quick decision-making, judging people’s emotions and willingness to buy. But he is very conscious about judging people by their looks, because, in his opinion, appearance has nothing to do with ability to purchase. Exercises can be performed to remove biases from snap judgments.

  • Remove biasing factors. Since it may be difficult or impossible to “learn away” biases, they can be removed from consciousness so they do not factor into the decision-making process. Many musical auditions now use screens to eliminate issues such as gender and race. Likewise, a hospital has been very successful in diagnosing heart conditions by focusing doctors only on particular elements of charts and away from demographics of the patient.

  • Retain factors if they matter. As a counterpoint to the previous guideline, blind tests led Coke to introduce the “New Coke” flavour, which bombed. Part of the problem was that branding and labels do affect people’s taste judgments, and the blind tests removed those.

Quick Thoughts

This was an interesting read and it certainly makes the benefits of short-term instincts clear. In particular, the interventions were the most interesting and practical element. What I disliked was the lack of structure. The text is not especially clear about its thesis and how various points relate to it. It reads more like a collection of essays about the general topic of short-term decision-making than an entire book.

Solipsistic Relevance to Software

  • As I mentioned in Software in a Blink, software design should ideally be intuitive, so that someone can get the structure in a blink. This means eliminating extraneous code, so you can focus on the high-level details. Steve Freeman recently provided an example by way of comparing dynamic to static syntax.
  • The discussion of experts reminded me of data mining studies. For instance, stock traders can eyeball a diagram and immediately spot trends that others would be oblivious to. User interfaces for experts should be designed to exploit those abilities. For instance, I once saw a system that showed prices row-by-row, without a fixed column format. So you could have “1.234” just above “123.4”. With no relationship between magnitude and text width, it was impossible for users to pick up patterns on the UI with which to make snap judgments.