The brands we buy are “the windows into our souls”

You should read this fascinating piece by Charles Duhigg in last week’s New York Times. A few tidbits to whet the appetite:

‘The exploration into cardholders’ minds hit a breakthrough in 2002, when J. P. Martin, a math-loving executive at Canadian Tire, decided to analyze almost every piece of information his company had collected from credit-card transactions the previous year. Canadian Tire’s stores sold electronics, sporting equipment, kitchen supplies and automotive goods and issued a credit card that could be used almost anywhere. Martin could often see precisely what cardholders were purchasing, and he discovered that the brands we buy are the windows into our souls — or at least into our willingness to make good on our debts…

‘His data indicated, for instance, that people who bought cheap, generic automotive oil were much more likely to miss a credit-card payment than someone who got the expensive, name-brand stuff. People who bought carbon-monoxide monitors for their homes or those little felt pads that stop chair legs from scratching the floor almost never missed payments. Anyone who purchased a chrome-skull car accessory or a “Mega Thruster Exhaust System” was pretty likely to miss paying his bill eventually.

‘Martin’s measurements were so precise that he could tell you the “riskiest” drinking establishment in Canada — Sharx Pool Bar in Montreal, where 47 percent of the patrons who used their Canadian Tire card missed four payments over 12 months. He could also tell you the “safest” products — premium birdseed and a device called a “snow roof rake” that homeowners use to remove high-up snowdrifts so they don’t fall on pedestrians…

‘Why were felt-pad buyers so upstanding? Because they wanted to protect their belongings, be they hardwood floors or credit scores. Why did chrome-skull owners skip out on their debts? “The person who buys a skull for their car, they are like people who go to a bar named Sharx,” Martin told me. “Would you give them a loan?”

So what if there are errors?

Now perhaps I’ve had too much training in science and mathematics, but this type of thinking seems totally neanderthal to me. It belongs in the same category of things we should be protected from as “guilt by association” and “racial profiling”.

For example, the article cites one of Martin’s concrete statistics:

‘A 2002 study of how customers of Canadian Tire were using the company's credit cards found that 2,220 of 100,000 cardholders who used their credit cards in drinking places missed four payments within the next 12 months. By contrast, only 530 of the cardholders who used their credit cards at the dentist missed four payments within the next 12 months.’

We can rephrase the statement to say that 98% of the people who used their credit cards in drinking places did NOT miss the requisite four payments.

Drawing the conclusion that “use of the credit card in a drinking establishment predicts default” is thus an error 98 times out of 100.

Denying people credit on a premise which is wrong 98% of the time seems like one of those things regulators should rush to address, even if the premise reduces risk to the credit card company.

But there won’t be enough regulators to go around, since there are thousands of other examples given that are similarly idiotic from the point of view of a society fair to its members. For the article continues,

‘Are cardholders suddenly logging in at 1 in the morning? It might signal sleeplessness due to anxiety. Are they using their cards for groceries? It might mean they are trying to conserve their cash. Have they started using their cards for therapy sessions? Do they call the card company in the middle of the day, when they should be at work? What do they say when a customer-service representative asks how they’re feeling? Are their sighs long or short? Do they respond better to a comforting or bullying tone?


  • Logging in at 1 in the morning. That’s me. I guess I’m one of the 98% for whom this thesis is wrong… I like to stay up late. Do you think staying up late could explain why Mr. Martin’s self-consciously erroneous theses irk me?
  • Using card to buy groceries? True, I don’t like cash. Does this put me on the road to ruin? Another stupid thesis for Mr. Martin.
  • Therapy sessions? If I read enough theses like those proposed by Martin, I may one day need therapy.  But frankly,  I don’t think Mr. Martin should have the slightest visibility into matters like these.  Canadian Tire meets Freud?
  • Calling in the middle of the day when I should be at work? Grow up, Mr. Martin. There is this thing called flex schedules for the 98% or 99% or 99.9% of us for which your theses continually fail.
  • What I would say if a customer-service representative asked how I was feeling? I would point out, with some vigor, that we do not have a personal relationship and that such a question isn't appropriate. And I certainly would not remain on the line.

Apparently Mr. Martin told Charles Duhigg, “If you show us what you buy, we can tell you who you are, maybe even better than you know yourself.” He then lamented that in the past, “everyone was scared that people will resent companies for knowing too much.”

At the best, this no more than a Luciferian version of the Beatles’ “You are what you eat” – but minus the excessive drug use that can explain why everyone thought this was so deep. The truth is, you are not “what you eat”.

Duhigg argues that in the past, companies stuck to “more traditional methods” of managing risk, like raising interest rates when someone was late paying a bill (imagine – a methodology based on actual delinquency rather than hocus pocus), because they worried that customers would revolt if they found out they were being studied so closely. He then says that after “the meltdown”, Mr. Martin’s methods have gained much more currency.

In fact, customers would revolt because the methodology is not reasonable or fair from the point of view of the vast majority of individuals, being wrong tens or hundreds or thousands of times more often than it is right.

If we weren’t working on digital identity, we could just end this discussion by saying Mr. Martin represents one more reason to introduce regulation into the credit card industry. But unfortunately, his thinking is contagious and symptomatic.

Mining of credit card information is just the tip of a vast and dangerous iceberg we are beginning to encounter in cyberspace. The Internet is currently engineered to facilitate the assembly of ever more information of the kind that so thrills Mr. Martin – data accumulated throughout the lives of our young people that will become progressively more important in limiting their opportunities as more “risk reduction” assumptions – of the Martinist kind that apply to almost no one but affect many – take hold.

When we talk about the need to prevent correlation handles and assembly of information across contexts (for example, in the Laws of Identity and our discussions of anonymity and minimal disclosure technology), we are talking about ways to begin to throw a monkey wrench into an emerging Martinist machine.  Mr. Duhigg's story describes early prototypes of the machinations we see as inevitable should we fail in our bid to create a privacy enhancing identity infrastructure for the digital epoch.

[Thanks to JC Cannon for pointing me to this article..]

Published by

Kim Cameron

Work on identity.