Coding Horror

programming and human factors

The Interview With The Programmer

If the internet has perfected anything, it's the art of the crappy, phoned-in, half-assed email "interview". For all those who have bemoaned the often pathetic state of internet journalism, when it comes to interviews, you're largely correct. The purpose of most of these interviews is quick and dirty content filler with semi-famous folk spouting off whatever random thoughts they happen to have in their head at that exact moment. The Nixon Interviews, it ain't.

That's why I'm normally not a huge fan of interview books, because interviews take an enormous amount of time and an enormous amount of legitimate, skilled journalistic effort to get right. Almost nobody does.

Imagine my surprise when Coders at Work: Reflections on the Craft of Programming turns out to be that wonderfully rare intersection of uncommonly skilled interviewing and 15 of the most influential programmers to ever touch a keyboard.


Yes, this is the same book Joel recently recommended in his controversial Duct Tape Programmer entry, which is why I was all the more skeptical. But he's dead on. I could (and probably will, knowing me) fill a year worth of blog posts just with the thought provoking quotes and two-paragraph insights revealed in these interviews. It's astonishingly good. If, after reading what these brilliant programmers have to say, you aren't motivated to research some programming topic mentioned inside, pack it in, because you aren't even trying any more.

I also realized Coders at Work can potentially serve as a job interview filter. If the next programmer you interview can't identify at least one of the programmers interviewed in Coders at Work and tell you roughly what they're famous for …

Frances AllenJoe ArmstrongJoshua Bloch
Bernie CosellDouglas CrockfordL. Peter Deutsch
Brendan EichBrad FitzpatrickDan Ingalls
Simon Peyton JonesDonald KnuthPeter Norvig
Guy SteeleKen ThompsonJamie Zawinski

… I'd say that's an immediate no-hire.

Incidentally, I saw the first Stack Overflow user reference on page 265, in the interview with Simon Peyton Jones, who mentions one Norman Ramsey. Hmm, I thought, that name sounds awfully familiar. And indeed it was!

I would be remiss if I did not mention that the author, Peter Seibel, was directly inspired by Susan Lammers' classic 1986 book Programmers at Work: Interviews With 19 Programmers Who Shaped the Computer Industry.


This is one of my absolute favorite musty old computer books for many of the same reasons. As sources of inspiration go, this one is particularly … er, inspired. Programmers at Work isn't just the archetypal programmer interview book -- it also holds up amazingly well for a book that is over twenty years old. It is a testament to the timelessness of not just code, but the art of coding, as exemplified by these 19 programmers. I believe Peter has legitimately crafted a modern remake that will be relevant for another twenty years. And I hope I don't have to tell you how extraordinarily rare that is among technical books.

(Some -- but not all from what I can tell -- key interviews from Programmers at Work were placed online last year by the author. So if you want to get a flavor of the book, check it out.)

Another notable recent collection of interviews is Masterminds of Programming: Conversations with the Creators of Major Programming Languages.


Although I definitely enjoyed this book, there's something about the focus on programming languages and interview style that didn't quite grab me as forcefully as Coders at Work did. Also, if we're going to do languages, I'd like to see a bit broader representation -- perhaps a Volume II with Smalltalk, Ada, Pascal and so on?

These books are a potent reminder that computers are mostly a reflection of the people using them. In the art of software development, studying code isn't enough: you have to study the people behind the software, too.


The State of Solid State Hard Drives

I've seen a lot of people play The Computer Performance Shell Game poorly. They overinvest in a fancy CPU, while pairing it with limited memory, a plain jane hard drive, or a generic video card. For most users, that fire-breathing quad-core CPU is sitting around twiddling its virtual thumbs most of the time. Computer performance is typically limited by the slowest part in your system. You'd get better overall performance by building a balanced system and removing bottlenecks.

One of those key bottlenecks -- and in my experience, the one typical users are most likely to underestimate -- is the hard drive. I've been a long time advocate of having a small, fast 10,000 RPM boot drive for your OS and key applications, and a larger, slower secondary drive for storage. The two drive approach is a smart strategy, regardless of your budget.

Hard drives may not be particularly sexy bits of hardware, but we're on the verge of a major transition point in storage hardware -- from physical, magnetic platters to solid state memory. I was an early solid state (SSD) drive adopter with my last laptop purchase, and it was a profound disappointment. Those first and second generation SSD drives turned out to be slower than their magentic equivalents, despite the eager promises of vendors. On top of that, they were incredibly expensive, and of limited capacity. Running Windows Vista on an early 32 gigabyte SSD was an exercise in pain and frustration on so many levels. What's not to love? A lot.

I eventually sold that SSD and replaced it with a traditional hard drive. I had grown deeply disillusioned with SSD drives. That is, until I read Linus Torvalds' report on the Intel X-25 SSD:

I can't recall the last time that a new tech toy I got made such a dramatic difference in performance and just plain usability of a machine of mine.

The whole thing just rocks. Everything performs well. You can put that disk in a machine, and suddenly you almost don't even need to care whether things were in your page cache or not. Firefox starts up pretty much as snappily in the cold-cache case as it does hot-cache. You can do package installation and big untars, and you don't even notice it, because your desktop doesn't get laggy or anything.

So here's the deal: right now, don't buy any other SSD than the Intel ones, because as far as I can tell, all the other ones are pretty much inferior to the much cheaper traditional disks, unless you never do any writes at all (and turn off 'atime', for that matter).

At that moment, SSD drives came of age. And by that I mean, they began to justify their hefty price premium at last. But that was almost a year ago, and even the Intel drives -- as great as they were -- had some teething problems. Not to mention that price and capacity were still ongoing concerns.

But when Intel introduced the second generation, mainstream X25-M drives, that's when I knew SSDs were poised to go mainstream. Now, those drives are still anything but cheap, at $289 for 80 GB and $609 for 160 GB. But they offer more performance than the original X25-E that Linus reviewed, at about half the price, with hardware fixes to address the fragmentation issue that plagued the original model.

Intel was the only game in town for about a year, but fortunately for us consumers, the competition finally caught up. The new Indilinx controller models, such as this Crucial 128 GB SSD, are just as fast as the X25-M. And, best of all, they're cheaper, while also offering a not-insubstantial bump to 128 GB of storage!


I picked this model up for $325 plus tax and shipping. And, frankly, I was blown away by the performance difference compared to the 300 GB Velociraptor I had in my system before. That drive is not exactly chopped liver; it's incredibly fast by magnetic platter drive standards. But it's beyond slow next to the latest SSDs. See for yourself:


This is just an excerpt, browse the reviews for more detail, but I was astonished how often this drive (based on the Indilinx Barefoot controller) topped the charts. Suffice it to say, the performance increase is not subtle. All those little pauses while your system pulls some chunk of data off the hard drive? They simply cease to exist.

How much do I like this drive? I like it so very much I bought one for every member of the Stack Overflow team, as a small gesture of thanks for enduring new feature crunch mode. I couldn't sell my old Velociraptor on eBay fast enough.

In my humble opinion, $200 - $300 for a SSD is easily the most cost effective performance increase you can buy for a computer of anything remotely resembling recent vintage. Whether you prefer the 80 GB X25-M SSD or the 128 GB Crucial SSD, it's money well invested for people like us who are obsessive about how their computer performs.

Trust me, you will feel the performance difference of a modern SSD in day to day computing. That's far more than I can say for most of today's CPU and memory upgrades. The transition from magnetic storage to solid state storage is nothing less than a breakthrough. It's already transformative; I can only imagine how fast, cheap, and large these drives are going to be in a few years. So, if you've ever wondered what performance would be like if everything was in RAM all the time -- well, we just got one giant step closer to that.


The Xanadu Dream

Links are the fundamental building blocks of the web. And every time I click on one, I can't help recalling the odd visionary who came up with the original idea of clickable links in text, aka hypertext, in 1963 -- Ted Nelson.

Ted Nelson is, shall we say, a character. He has gone on record many times with the four maxims that guide his life. He isn't shy about sharing them with anyone he meets:

  • most people are fools
  • most authority is malignant
  • God does not exist
  • everything is wrong

And that, in a nutshell, is pretty much everything you need to know about Ted Nelson. He is the archetypal borderline autistic, non-conformist, free-thinking technologist. Any resemblance between Ted and your average programmer is, I'm sure, completely coincidental. That's why his story is so fascinating to me. It hits close to home.

Like most programmers, Ted's reach often exceeded his grasp. Ted's vision of hypertext was far more grandiose than the motley assortment of links that is today's web. His vision was (and is) a bit of computer history lore that has become the stuff of legend: Project Xanadu.

Xanadu, a global hypertext publishing system, is the longest-running vaporware story in the history of the computer industry. It has been in development for more than 30 years. This long gestation period may not put it in the same category as the Great Wall of China, which was under construction for most of the 16th century and still failed to foil invaders, but, given the relative youth of commercial computing, Xanadu has set a record of futility that will be difficult for other companies to surpass. The fact that Nelson has had only since about 1960 to build his reputation as the king of unsuccessful software development makes Xanadu interesting for another reason: the project's failure (or, viewed more optimistically, its long-delayed success) coincides almost exactly with the birth of hacker culture. Xanadu's manic and highly publicized swerves from triumph to bankruptcy show a side of hackerdom that is as important, perhaps, as tales of billion-dollar companies born in garages.


Among people who consider themselves insiders, Nelson's Xanadu is sometimes treated as a joke, but this is superficial. Nelson's writing and presentations inspired some of the most visionary computer programmers, managers, and executives - including Autodesk Inc. founder John Walker - to pour millions of dollars and years of effort into the project. Xanadu was meant to be a universal library, a worldwide hypertext publishing tool, a system to resolve copyright disputes, and a meritocratic forum for discussion and debate. By putting all information within reach of all people, Xanadu was meant to eliminate scientific ignorance and cure political misunderstandings. And, on the very hackerish assumption that global catastrophes are caused by ignorance, stupidity, and communication failures, Xanadu was supposed to save the world.

The above text is excerpted from the definitive 1995 Wired article on Project Xanadu, which is still as electrifying to read today as it was then. The hubris and sheer scale of the Xanadu dream are at turns both inspiring and desperately, hopelessly out of touch.

Xanadu has 17 rules defining its behavior. As you're reading through this list, ask yourself how many of these rules are satisfied by the current world wide web, even in part:

  1. Every Xanadu server is uniquely and securely identified.
  2. Every Xanadu server can be operated independently or in a network.
  3. Every user is uniquely and securely identified.
  4. Every user can search, retrieve, create and store documents.
  5. Every document can consist of any number of parts each of which may be of any data type.
  6. Every document can contain links of any type including virtual copies ("transclusions") to any other document in the system accessible to its owner.
  7. Links are visible and can be followed from all endpoints.
  8. Permission to link to a document is explicitly granted by the act of publication.
  9. Every document can contain a royalty mechanism at any desired degree of granularity to ensure payment on any portion accessed, including virtual copies ("transclusions") of all or part of the document.
  10. Every document is uniquely and securely identified.
  11. Every document can have secure access controls.
  12. Every document can be rapidly searched, stored and retrieved without user knowledge of where it is physically stored.
  13. Every document is automatically moved to physical storage appropriate to its frequency of access from any given location.
  14. Every document is automatically stored redundantly to maintain availability even in case of a disaster.
  15. Every Xanadu service provider can charge their users at any rate they choose for the storage, retrieval and publishing of documents.
  16. Every transaction is secure and auditable only by the parties to that transaction.
  17. The Xanadu client-server communication protocol is an openly published standard. Third-party software development and integration is encouraged.

It is instructive, then, to consider the primary ways in which the modern web is functionally broken:

  • Link rot. The odds of a hyperlink working are inversely proportional to the age of that hyperlink. Old links frequently break, because the server hosting the content disappears for any number of reasons over time. I've gotten to the point where I dread clicking on links from old web pages, because the per-click success rate is so abysmally low.
  • Every website has unique usernames and passwords. There is almost no reliable centralized form of identity on the internet, and those few that do exist are often poisoned by explicit commercial affiliation, such as Facebook Connect and Microsoft Passport. This is why curated anonymous, lightweight participation dominates the net -- best illustrated by Wikipedia.
  • No redundancy. If content is driven offline by temporary high traffic levels or, worse, catastrophic data loss, there may not be any way to recover that content. I know that Digg has services which auto-mirror highly rated links because Digg traffic can be so toxic to the destination links. (Ironically, all links redirect to now, which illustrates how ephemeral all this stuff tends to be.) I suppose if you're lucky the wayback machine will eventually pick up a historical copy of the content, or the Google cache will hold a copy for some unknown amount of time while the site is offline. You'd probably have better odds praying for missing content to reappear.

Let's put aside the more ambitious parts of Project Xanadu for the moment. The current world wide web does basically one thing: simple, stupid, mindless hyperlinks. But even that alone was enough to build a functional and useful internet for the world. And Google was able to build a zillion dollar algorithm out of discovering the relationship between those dumb hyperlinks.

All that, when the most fundamental building block of the web, the hyperlink, barely works at all. Hyperlinks are fraught with peril and pitfalls even under the best of conditions. The current state of hyperlinking is almost literally the stupidest thing we could build that works. Frankly, the current system sucks beyond belief, as Ted himself notes:

HTML is precisely what we were trying to prevent -- ever-breaking links, links going outward only, quotes you can't follow to their origins, no version management, no rights management.

The next time you're about to embark on a grandiose, glorious software Xanadu Dream of your own, take Dare's advice.

The bottom line is that a lot of the time it's OK to create a solution that solves 80% of the problem. Always remember that shipping is a feature.

Consider the reality of what's actually possible, what people can understand, and what us all too human programmers can practically implement. It might not be the Xanadu you dreamed of -- heck, it might even suck – but it'll at least have a fighting chance of existing in reality rather than fantasy.


Email: The Variable Reinforcement Machine

How often do you check your email per day?

Does checking your email make you more productive or less productive?

Oh, sure, we delude ourselves into thinking we're being extra-productive by obsessively checking and responding to our email, but in reality we're attending too frequently to our own desire for gratification and sabotaging our own productivity in the process.

As Dan Ariely explains in a postscript to Predictably Irrational, he smells a rat, and so should you:

Skinner distinguished between fixed-ratio schedules of reinforcement and variable-ratio schedules of reinforcement. Under a fixed schedule, a rat received a reward of food after it pressed the lever a fixed number of times -- say 100 times. Under the variable schedule, the rat earned a food pellet after it pressed the lever a random number of times. Sometimes it would receive the food pellet after pressing 10 times, and sometimes after pressing 200 times.

Under the variable schedule of reinforcement, the arrival of the reward is unpredictable. On the face of it, one might expect that the fixed schedules of reinforcement would be more motivating and rewarding because the rat can learn to predict the outcome of his work. Instead, Skinner found that the variable schedules were actually more motivating. The most telling result was that when the rewards ceased, the rats who were under the fixed schedule stopped working almost immediately, but those under the variable schedules kept working for a very long time.

If this reminds you of gambling, that's because gambling explicitly works under the very same schedule of variable reinforcement.


Go ahead, pull the "new email' lever. Take a chance. Most of the time you'll end up a loser, the proud recipient of yet another spam email, a press release you don't care about, or some irrelevant conversation someone has cc:ed you into. But not always. There are those rare few times when you'll hit the jackpot: you'll get an important bit of information you needed, or tentative contact from a long lost friend or associate, or other good news.

We're so ecstatic to get that single useful email out of hundreds that we can't keep ourselves from compulsively pressing the new email lever over and over and over, hoping it will happen again soon, like the caged rats in Skinners' experiments.

We desperately need to ask ourselves, and those around us, to revisit the purpose of email. Given what we know about the importance of flow to productive work, and how multi-tasking is largely a myth, is it worth the constant stream of minor interruptions?

We've overloaded email with so many meanings that it has imploded as a communication medium. Need an urgent answer to your question within a few minutes? Fire off a quick email and demand a response! Want to have a long back and forth discussion with several people? Email everyone! Do you have a new theory that you desperately want to explain to someone? Send it to them via email! Got a funny joke or picture you're dying to share? Email it to the office alias!

When we treat email as the kitchen sink of communication, appropriate for everything, it simply ceases to work at all.

Kathy Sierra was concerned that Twitter had the same variable reinforcement problem, but I think Twitter is in fact part of the answer to the problem.

Stop. Sending. Email.

Instead of abusing email as a "one size fits all" conduit for communication, be smart. Know when to escalate your communication to the right medium for the particular message you're trying to deliver:

  • Broad kudos? Post it on a feedback forum or your blog.
  • Need an urgent, immediate answer? Pick up the phone and call.
  • Got something that needs a lot of touchy feely discussion? Set up a face to face meeting.
  • Discussing a particular topic or product? Post it on a public message board.
  • Is this more of a friendly, social thing? Try using a social network like Twitter or Facebook.
  • Business proposal? Perhaps it would be smart to approach indirectly, through soliciting recommendations of business associates.

The real solution here is to move people beyond email silos wherever and whenever possible. Some amount of email is still inevitable, though. What steps can we take to turn our email from a dangerous variable reinforcement machine to something more … sane? Predictable, even?

  • Turn off all notification and interruption features in your email client.
  • Only check your email at regular, scheduled intervals.
  • Set up your email client to automatically highlight those emails from friends and business associates who are historically known to send you useful email.

Before you send that next email -- or press the "retrieve mail" button again -- ask yourself: do I smell a rat?


9 Ways Marketing Weasels Will Try to Manipulate You

I recently read Predictably Irrational.


It's a fascinating examination of why human beings are wired and conditioned to react irrationally. We human beings are a selfish bunch, so it's all the more surprising to see how easily we can be manipulated to behave in ways that run counter to our own self-interest.

This isn't just a "gee-whiz" observation; understanding how and why we behave irrationally is important. If you don't understand how these irrational behaviors are triggered, the marketing weasels will use them against you.

In fact, it's already happening. Witness 10 Irrational Human Behaviors and How to Leverage Them to Improve Web Marketing. Don't say I didn't warn you.

Let's take a look at the various excerpts presented in that article, and consider how we can avoid falling into the rut of predictably irrational behavior – and defend ourselves from those vicious marketing weasels.

1. Encourage false comparisons

When Williams-Sonoma introduced bread machines, sales were slow. When they added a "deluxe" version that was 50% more expensive, they started flying off the shelves; the first bread machine now appeared to be a bargain

When contemplating the purchase of a $25 pen, the majority of subjects would drive to another store 15 minutes away to save $7. When contemplating the purchase of a $455 suit, the majority of subjects would not drive to another store 15 minutes away to save $7. The amount saved and time involved are the same, but people make very different choices. Watch out for relative thinking; it comes naturally to all of us.

  • Realize that some premium options exist as decoys – that is, they are there only to make the less expensive options look more appealing, because they're easy to compare. Don't make binding decisions solely based on how easy it is to compare two side-by-side options from the same vendor. Try comparing all the alternatives, even those from other vendors.
  • Don't be swayed by relative percentages for small dollar amounts. Yes, you saved 25%, but how much effort and time did you expend on that seven bucks?

2. Reinforce Anchoring

Savador Assael, the Pearl King, single-handedly created the market for black pearls, which were unknown in the industry before 1973. His first attempt to market the pearls was an utter failure; he didn't sell a single pearl. So he went to his friend, Harry Winston, and had Winston put them in the window of his 5th Avenue store with an outrageous price tag attached. Then he ran full page ads in glossy magazines with black pearls next to diamonds, rubies, and emeralds. Soon, black pearls were considered precious.

Simonsohn and Loewenstein found that people who move to a new city remain anchored to the prices they paid in their previous city. People who move from Lubbock to Pittsburgh squeeze their families into smaller houses to pay the same amount. People who move from LA to Pittsburgh don't save money, they just move into mansions.

  • Scale your purchases to your needs, not your circumstances or wallet size. What do you actually use? How much do you use it, and how frequently?
  • Try to objectively measure the value of what you're buying; don't be tricked into measuring relative to similar products or competitors. How much does buying this save you or your company? How much benefit will you get out of it? Attempt to measure that benefit by putting a concrete dollar amount on it.

3. It's "Free"!

Ariely, Shampanier, and Mazar conducted an experiment using Lindt truffles and Hershey's Kisses. When a truffle was $0.15 and a kiss was $0.01, 73% of subjects chose the truffle and 27% the Kiss. But when a truffle was $0.14 and a kiss was free, 69% chose the kiss and 31% the truffle.

According to standard economic theory, the price reduction shouldn't have lead to any behavior change, but it did.

Ariely's theory is that for normal transactions, we consider both upside and downside. But when something is free, we forget about the downside. "Free" makes us perceive what is being offered as immensely more valuable than it really is. Humans are loss-averse; when considering a normal purchase, loss-aversion comes into play. But when an item is free, there is no visible possibility of loss

  • You will tend to overestimate the value of items you get for free. Resist this by viewing free stuff skeptically rather than welcoming it with open arms. If it was really that great, why would it be free?
  • Free stuff often comes with well hidden and subtle strings attached. How will using a free service or obtaining a free item influence your future choices? What paid alternatives are you avoiding by choosing the free route, and why?
  • How much effort will the free option cost you? Are there non-free options which would cost less in time or effort? How much is your time worth?
  • When you use a free service or product, you are implicitly endorsing and encouraging the provider, effectively beating a path to their door. Is this something you are comfortable with?

4. Exploit social norms

The AARP asked lawyers to participate in a program where they would offer their services to needy employees for a discounted price of $30/hour. No dice. When the program manager instead asked if they'd offer their services for free, the lawyers overwhelmingly said they would participate

  • Companies may appeal to your innate sense of community or public good to convince you to do their work at zero pay. Consider carefully before choosing to participate; what do you get out of contributing your time and effort? Is this truly a worthy cause? Would this be worth doing if it was a paid gig?
  • When it comes to the web, make sure you aren't being turned into a digital sharecropper.

5. Design for Procrastination

Ariely conducted an experiment on his class. Students were required to write three papers. Ariely asked the first group to commit to dates by which they would turn in each paper. Late papers would be penalized 1% per day. There was no penalty for turning papers in early. The logical response is to commit to turning all three papers in on the last day of class. The second group was given no deadlines; all three papers were due in the last day of class. The third group was directed to turn their papers in on the 4th, 8th, and 12th weeks.

The results? Group 3 (imposed deadlines) got the best grades. Group 2 (no deadlines) got the worst grades, and Group 1 (self-selected deadlines) finished in the middle. Allowing students to pre-commit to deadlines improved performance. Students who spaced out their commitments did well; students who did the logical thing and gave no commitments did badly.

  • Steer clear of offers of low-rate trial periods which auto-convert into automatic recurring monthly billing. They know that most people will procrastinate and forget to cancel before the recurring billing kicks in.
  • Either favor fixed-rate, fixed-term plans – or become meticulous about cancelling recurring services when you're not using them.

6. Utilize the Endowment Effect

Ariely and Carmon conducted an experiment on Duke students, who sleep out for weeks to get basketball tickets; even those who sleep out are still subjected to a lottery at the end. Some students get tickets, some don't. The students who didn't get tickets told Ariely that they'd be willing to pay up to $170 for tickets. The students who did get the tickets told Ariely that they wouldn't accept less than $2,400 for their tickets.

There are three fundamental quirks of human nature. We fall in love with what we already have. We focus on what we might lose, rather than what we might gain. We assume that other people will see the transaction from the same perspective as we do.

  • The value of what you've spent so far on a service, product, or relationship – in effort or money – is probably far less than you think. Be willing to walk away.
  • Once you've bought something, never rely on your internal judgment to assess its value, because you're too close to it now. Ask other people what they'd pay for this service, product, or relationship. Objectively research what others pay online.

7. Capitalize on our Aversion to Loss

Ariely and Shin conducted an experiment on MIT students. They devised a computer game which offered players three doors: Red, Blue, and Green. You started with 100 clicks. You clicked to enter a room. Once in a room, each click netted you between 1-10 cents. You could also switch rooms (at the cost of a click). The rooms were programmed to provide different levels of rewards (there was variation within each room's payoffs, but it was pretty easy to tell which one provided the best payout).

Players tended to try all three rooms, figure out which one had the highest payout, and then spend all their time there. (These are MIT students we're talking about). Then, however, Ariely introduced a new wrinkle: Any door left unvisited for 12 clicks would disappear forever. With each click, the unclicked doors shrank by 1/12th.

Now, players jumped from door to door, trying to keep their options open.They made 15% less money; in fact, by choosing any of the doors and sticking with it, they could have made more money.

Ariely increased the cost of opening a door to 3 cents; no change–players still seemed compelled to keeping their options open. Ariely told participants the exact monetary payoff of each door; no change. Ariely allowed participants as many practice runs as they wanted before the actual experiment; no change. Ariely changed the rules so that any door could be "reincarnated" with a single click; no change.

Players just couldn't tolerate the idea of the loss, and so they did whatever was necessary to prevent their doors from closing, even though disappearance had no real consequences and could be easily reversed. We feel compelled to preserve options, even at great expense, even when it doesn't make sense.

  • If your choices are artificially narrowed, don't passively get funneled towards the goal they're herding you toward. Demand choice, even if it means switching vendors or allegiances.
  • Don't pay extra for options, unless you can point to hard evidence that you need those options. Some options exist just to make you doubt yourself, so you'll worry about not having them.

8. Engender Unreasonable Expectations

Ariely, Lee, and Frederick conducted yet another experiment on MIT students. They let students taste two different beers, and then choose to get a free pint of one of the brews. Brew A was Budweiser. Brew B was Budweiser, plus 2 drops of balsamic vinegar per ounce.

When students were not told about the nature of the beers, they overwhelmingly chose the balsamic beer. When students were told about the true nature of the beers, they overwhelmingly chose the Budweiser. If you tell people up front that something might be distasteful, the odds are good they'll end up agreeing with you–because of their expectations.

  • Whatever you've heard about a brand, company, or product – there's no substitute for your own hands-on experience. Let your own opinions guide you, not the opinions of others.
  • Just because something is labelled "premium" or "pro" or "award-winning" doesn't mean it is. Research these claims; don't let marketing set your expectations. Rely on evidence and facts.

9. Leverage Pricing Bias

Ariely, Waber, Shiv, and Carmon made up a fake painkiller, Veladone-Rx. An attractive woman in a business suit (with a faint Russian accent) told subjects that 92% of patients receiving VR reported significant pain relief in 10 minutes, with relief lasting up to 8 hours.

When told that the drug cost $2.50 per dose, nearly all of the subjects reported pain relief. When told that the drug cost $0.10 per dose, only half of the subjects reported pain relief. The more pain a person experienced, the more pronounced the effect. A similar study at U Iowa showed that students who paid list price for cold medications reported better medical outcomes than those who bought discount (but clinically identical) drugs.

  • Price often has nothing to do with value. Expensive is not synonymous with quality. Investigate whether the price is justified; never accept it at face value.
  • Don't fall prey to the "moneymoon"; just because you paid for something doesn't mean it's automatically worthwhile. Not everything we pay money for works well, or was even worth what we spent for it. We all make mistakes when buying things, but we don't want to admit it.

What I learned from Predictably Irrational is that everyone is irrational sometimes, and that's OK. We're not perfectly logical Vulcans, after all. The trick is training yourself to know when you're most likely to make irrational choices, and to resist those impulses.

If you aren't at least aware of our sad, irrational human condition, well … that's exactly where the marketing weasels want you.