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Thanks to this blog post by my former colleague, Dr. Dan Reeves, I have been thinking about commitment devices, when they work, and what they're good for.
A commitment device is a way of enforcing a decision you make today on yourself in the future. For instance, "Christmas Club" accounts—savings accounts that earn no interest but cannot be withdrawn from until December—force one to stick to the decision of not spending money until the gift-giving holiday. Remember that bet you made with your friend that you'll lose 10 pounds before some important date (your wedding, perhaps?)—that's a commitment device, too. The fact that we sometimes have to use tricks to get ourselves to do what we really want to do says a lot about the interaction between planning and willpower. Commitment devices are most commonly applied to addictive behaviors, but they can be used in any situation in which you trust the decision you are making at the moment more than the decision you will make down the road.
The problem addressed by commitment devices has to do with the difference between long-term, abstract goals and short-term, concrete stimuli. Consider this anecdote from classic behaviorist research. There was a dog trapped in a cage with a latch, which the dog could open using its muzzle. When a steaming hot turkey leg was placed in front of the dog, the stimulus was so overwhelming that the dog focused only on the meat and not on the problem of the latch, and therefore was unable to get to the meat. After the meat had cooled, however, and the stimulus was no longer so intense, the dog was able to figure out how to open the latch and get to the meat. For people, when removed in time from that tempting jelly donut, it is easy to consider the costs and benefits of eating the donut, but when it is right in front of you the stimulus can overwhelm reason.
A related concept from psychology is the planning fallacy. People have the tendency to view future events in abstract terms, and thus over-emphasize abstract benefits such as "feeling good about oneself" and de-emphasize concrete costs, such as "exercise hurts." In fact, there is a lot of evidence that we are bad at predicting what our future self will do in many situations. As Dan cleverly put it, "The myopic future self that thwarts your intentions is every bit as smart as your current, forward-looking self."
One of the difficulties of most commitment devices, Dan realized, is that they tend to be situated around a single deadline, rather than daily actions. So if the goal is to lose 10 pounds before your wedding, you may not really find the motivation to start acting on it (by cutting out those tasty desserts, for instance) until it is too late. To remedy this, he invented an online tracking system called Beeminder that gives you a path (the "yellow brick road" in Beeminder parlance) to follow towards your goal. With this path, you can now setup a commitment device of the form "I bet you $100 I won't stray too far off this path", or whatever penalty you want to incur. This way if you're already slipping away from your goal, or not approaching it quickly enough, that decision you make today could make you lose the bet today. There is no future you to worry about, because on every day the bet is about that day.
I think Beeminder is an excellent idea, as it conquers one of the weaknesses of commitment devices: the fact that you can always procrastinate until the deadline is tomorrow—at which point it could be too late. However, I feel there is another potential weakness for commitment devices, and that is how that commitment is enforced. In keeping with the theme of this blog, I'm particularly interested in how friends rely on each other for this sort of wager.
For instance, Dan made a bet that he will stick to one of his "yellow brick roads", and if he slips, any of his friends can claim $1000 if they catch him. Because I know him fairly well, I understand that's something he really wants, and his true friends would have no qualms about taking the money. But for many people, and many friendships, taking $1000 from a friend just because they lost a bet would be quite difficult. As a friend, you might grant them leniency: tell them you'll take the money, but if they don't succeed, let them keep it. Of course, this undermines the whole principle of the commitment device.
I remember one time a friend (let's call him John) asked his friend (let's call him Paul) to never give him another cigarette. Paul agreed, but when the time came and John was experiencing nicotine withdrawal, he made it very hard for Paul to refuse, laying on a guilt trip and insisting he didn't really mean it when he asked Paul for his help in the first place. For addictive substances, at least, there is some sense that you're doing the right thing for the person by giving "tough love" and refusing to enable the addictive behavior. But when it comes to something less health-threatening, it can be much harder to justify denying your friend's current self because of something their past self made you promise. Which "friend" is your better friend?
This is a situation where having a tight-knit social group can be very beneficial. Instead of asking just one friend to help you keep your commitment to yourself, you could ask many or all of your friends, who are likely also friends with each other, for their support. Then, when they need to be hard on you, they can get support from each other. It becomes a team effort, so no one individual is shouldering the burden of the commitment. It is this sort of thing that James Coleman was referring to when describing "social capital." There is strong evidence that communities of support can lead to better outcomes for individuals in the groups. I'm not sure if the same research has been applied to simple commitment devices, but I would be surprised if it worked any differently.
So remember: if there is something you want to do but have a hard time committing to it, and especially if the commitment requires regular actions, try two things. First, use a commitment device such as Beeminder that makes the path to your goal the real goal. And second, get mutual friends involved in supporting your commitment. One friend alone might grant you leniency, but the more friends you have enforcing your decision, the easier it will be for any one of them to help keep you on track.
