Thomas Denney

New Year's nudges

It is a truth universally acknowledged that New Year’s resolutions do not work. Each year as January rolls around we set ourselves noble goals to exercise more, lose weight, eat more healthily, smoke less, or sleep more. Yet 88% of these resolutions are doomed to fail.

As much as our intentions may be good, New Year’s resolutions mostly fail through poor goal setting: all of the above are much to vague for a start. Plenty has already been written in favour of using SMART goals but I think we should approach resolutions differently.

The above study found that about half the participants even expected their resolutions to fail. That’s pretty poor, but falls well within our cultural experience of New Year’s resolutions: often our resolutions are just something we come up with off the cuff at a New Year’s Eve party or around the water cooler in early January.1 We might stick with them for a few days, but beyond that there’s not much hope.

Instead, let’s find goals that are easy to implement, and that if implemented are likely to succeed. Most traditional New Year’s resolutions seek to maximise the effect of their change, without taking into account its probability of succeeding. If we instead seek to maximise the expected outcome of the change, we can look at maximising the probability of success. In loose Bayesian terms we might write:

P(success) = P(succcess | implementation) * P(implementation)
E(change)  = effect of change * P(success)

If we’re looking for easy, small changes then nudge theory can serve us well: nudges are changes that alter behaviour in a predictable way, but must be cheap, easy to implement, and not forbid other choices. Sounds perfect! Most nudge literature is written for “choice architects” designing for other people’s decision making, but we can readily apply many of the techniques to ourselves.

Good defaults are essential to nudging: if we automatically fall down “the right path” then we’re maximising P(success | implementation) because we don’t need to do anything differently once we’ve implemented the change. By making the change easy, we maximise P(implementation).

A classic example from nudge theory finds that moving healthy snacks, such as fruit, to eye level and making unhealthier snacks less accessible increases healthy snack sales.2 If we’d like to be healthier then eating more fruit is a good start. Here we can take advantage of behavioural shifts from the last year: many of us now buy groceries online rather than in store, and most supermarket sites allow you to create a “default basket” for essentials. Adding more fruit to this, and then placing it where you’d usually put snacks, could be an easy way to get started.

Alternatively, we may have the goal of saving more money. Many banking apps now offer a feature that will “round up” transactions to the nearest pound or dollar, placing the remainder in a savings account. The initial set-up effort takes seconds, and the probability of success given implementation is certain. You’ll save a modest amount of money, but it’s certainly better than nothing.

I’ve recently attempted to sleep better. My sleep was often disrupted by a bright street light, so I installed better black-out curtains. This took less than an hour of DIY (easy to implement) and I draw the curtains each night anyway (default behaviour). It’s already paying dividends.

As we all face another stressful, draining year in a global pandemic, I think it’s high time we abandon over-ambitious resolutions: let’s find small, easy nudges that may actually improve our lives.

  1. Or in 2020-21, on Zoom.↩︎

  2. The other “classic” example is that adding stickers of a fly to urinals improves aim; there are even companies selling stickers for this purpose.↩︎