I recently read Nudge (Amazon US & Amazon UK), a book that got quite a bit of press coverage here in the UK after inspiring some political decisions on both sides of the floor.

Its core premise is that human decisions are not taken on pure economic terms (though economic factors do play a large part as presented in books such as Freakonomics and The Undercover Economist) (*).

The authors introduce a concept of choice architecture which is defined as differences in the way that decisions are structured or presented that can change the outcomes even while having no (or negligible) impact on the economic preferences of the chooser. The simplest examples of this that stuck in my mind were:

  1. research has shown that people choose different amounts of dessert depending on where it is positioned relative to other food in cafeterias. There is no particular rational reason why you would want to eat more dessert depending on where it is positioned (indeed most of us would probably like to think we were immune to such manipulation) but it's apparently a widespread effect
  2. employees apparently save more as a proportion of their salary when paid every other week versus being paid monthly - even when their salary remains the same on an annual basis. The hypothesis presented for this effect is that people still budget monthly even when paid bi-weekly and therefore when they get two months a year with 3 payments they largely put them towards savings. Interestingly, I believe it much more common to be paid every other week in the US than the UK where salary payments are almost universally made monthly as far as I know (and where the tax system is set up to work that way)

Note that in most of these cases we cannot choose not to create a choice architecture. We have to present the choice somehow (assuming we are going to offer dessert in our cafeterias and that we are going to pay our employees!) and therefore we can't choose not to nudge and we must simply decide how to nudge.

So what has this got to do with SEO?

Well, as I was reading the book, I couldn't help referring their thoughts to my experiences. These are inevitably about business or SEO and so I thought I would write a post to outline the main themes of the book and highlight where I thought the ideas could be applied to SEO or SEO businesses. Since so many are about human weaknesses (or at least human effects) I have applied some to conversion rate optimisation (which is an important consideration when talking about traffic from search) since the search engines are generally not susceptible to human-based nudges. If you are concerned about manual reviews, I expect there is a lot you could think about to help nudge a human reviewer into giving your site a positive review, but that's a subject for another day.

Before I get into that, I thought I would introduce one of the provisos the authors mention. They say that they believe in what they call Libertarian Paternalism. As they acknowledge, one or other of those words is pretty much guaranteed to annoy you (which one will depend on your politics!). Their view is that nudges shouldn't incorporate the removal of any options (the 'Libertarian' part) - so if we are nudging someone towards a decision we believe will be good for them (as they argue we should - the 'Paternalism' part!) we should still allow them to make 'poor' decisions if they wish.

It strikes me that this is a kind of unenforceable guideline and in reality we are simply better prepared by thinking about the effectiveness of a nudge than about whether it is libertarian or paternalist. Does this make me a black-hat nudger?

Without further ado, here are the main themes from the book and my thoughts on their application to SEO and SEO businesses:

More choice = better?

There has been a widespread movement (particularly in the public sector) to believe that more choices are always better than fewer choices. This comes from the economic argument that since any larger set of choices includes all the options you had under a smaller set of choices you can't possibly be worse off (since you can still choose any of the old options) and so you must be at least as well off (and possibly better off) with more choices.

Nudge argues that this isn't actually in keeping with human nature and that in fact people can be overwhelmed by choice and either choose to do nothing or choose poorly when presented by many options.


The first of many human frailties presented in the book, anchoring comes from the tendency of the human brain to grasp for patterns. Even when we know full well that a number is random, it can have an effect on our estimates of other numbers. For example, if you ask someone the last three digits of their credit card number and then ask them to estimate some other number that falls in a similar range (such as the year of Attilla the Hun's attack on Europe), people with higher numbers at the end of their credit card (e.g. 987) guess higher than those with lower numbers (e.g. 123) even though any rational person knows full well that there is no relationship between the two numbers.

Using this information

I imagine that this kind of psychology knowledge could help make linkbait more effective. There are many forms of linkbait that rely on some element of discovery or surprise. By initially anchoring expectations in a different direction, the surprise experienced when the actual answer is revealed can be heightened. Since surprise is a common reason for passing along content ("did you know?"), this increases the linkability. Next time you are writing something a bit surprising as linkbait, try anchoring expectations in a different direction first.

It is a well-known negotiating ploy to get someone thinking about a particularly high number before (pleasantly) surprising them with a number much lower (but still perhaps high). I'll leave you to construct your own ways of using that information! As you do so, remember another effect which comes from framing. People generally behave differently to one price option being "premium" versus the other compared to the second option being "discount" versus the first. The prices could be exactly the same, but the way they are framed can cause real effects.

One other area where I think it is important to think about this is in time estimation. We are all bad at estimating time I think. Whether talking about development resource or time for effects to be realised, we need to know that the other person's expectations are affected by anchoring. If you want a generous estimate, get them talking about something that's going to happen next year before asking how long it will take. If you want an ambitious estimate, talk about what you're doing this evening. If you want an accurate estimate, um, well, don't we all?!


People tend to over-weight things close at hand (whether it be personal experiences over those they have heard about or more recent events over older ones).

Using this information

When trying to get someone to do something (whether it be link to you or buy something from your website) you would do well to get them in the frame of mind of a time they did something similar and it went well. In linkbuilding terms, this might be mentioning another outbound link they have on their site already that is similar to the one you seek. In CRO terms, it might be designing your UI to resemble bigger more popular online stores that everyone has experience of using.

Remember that the weight people put on experiences tends to decrease as you move from experiences they had to experiences their friends had to experiences they just heard about. This is why trials and low-commitment business tactics work well - once people have tried something first-hand, they are far more likely to trust statements made about it than they were before trying it.


An unwieldy name for an unwieldy concept. This is the common error that says that if you have in your mind what a class of things should "look like" then anything that "looks like" that description is likely to be classified by your unconscious mind as being one of those things. The most famous experiment demonstrating this bias is as follows:


People were presented with that description and then asked to estimate the probability of possible futures for Linda. Included in the list of options were "bank teller" and "bank teller active in the feminist movement". Many people apparently ranked the second as more likely than the first (despite the obvious logic mistake preventing that possibility).

Using this information

I haven't really thought of any good applications of this bias. I'd be interested to hear yours in the comments. One other common manifestation of the representativeness bias is the inability for many to believe that outcomes of many things are random because they don't 'look' random. This has an impact on the presentation of data in reporting. It is important that you give clients or bosses tools for assessing real trends in numbers like conversions or traffic because otherwise there will be a strong chance that random fluctuations will be seen as real trends - causing painful future issues!

Optimism and confidence

People are generally more optimistic about their own future than they should be. When asked the chances of their business failing and about the chances of "businesses like yours" failing, business owners tend to give drastically different answers (sometimes as much as 0% vs. 30% when asked about the next year).

Using this information

This is more one to avoid common pitfalls over (like the representativeness bias) than one where I have come up with good 'uses'. Remember that bosses and clients will believe their project / linkbait / website implementation will have a greater chance of success than equivalent projects even with no good reason. Beware!

Gains vs. losses

It is quite well known that most people fear losses far more than they value gains (compulsive gamblers can sometimes be found swapping these two traits).

Using this information

This effect leads to an even more powerful one which is a preference for the status quo (no, not necessarily a preference for Status Quo). It is only one of the reasons why people prefer things to stay the way they are (simple inertia being one other). But it leads to powerful effects - if you can just get someone to take an action that changes the default then it is likely that you will continue to benefit.

In linkbuilding - if you can convince someone to put a link somewhere for a short period of time (perhaps while a topic is particularly relevant or *gasp* with a one-off incentive) then it is very likely that link will remain there for some time. Equally if someone subscribes to an email list or starts a subscription, they will tend to remain on it for longer than they might have guessed they would.

Mental accounting and fungibility

I love the word 'fungible'. It has nothing to do with mushrooms. It is a property of things (like money) where any one is as good as any other (you have no rational reason to prefer one $20 bill over any other $20 bill). Despite being aware of this, many people don't treat money as being fungible. They mentally account for things ("the money in that account is for my rent, while the money in my wallet is for dinner") - many people are amazingly reluctant to take money from the wrong account even for very short periods of time.

Using this information


In a similar way, you may have more luck getting a link from a page that doesn't have advertising on it than one that does (while the two are relatively fungible to you, the seller may think of them differently).

Priming and the measurement effect

Much like the anchoring bias discussed above, people behave differently if you simply ask them in advance what they intend to do. Asking people the day before voting day if they intend to go to the polls tomorrow increases the chances that they actually will.

Using this information

Charities know this effect well - many donation requests are preceded by questions about how much you care about different issues. If you are in a situation where this would work in your favour when linkbuilding, it can be a very effective tactic. Start a relationship with a survey and follow-up with a request (where one of the survey questions asked if they would do the thing you then request). This only works if they feel they "should" do it - use sparingly! I think it is closely related to the herd effect where people want to do what others are doing.

You can use the herd effect through social reinforcement in so many ways. It is why signs of others having liked a story make it more likely to be shared by others. You could consider this the next time you are embedding social bookmarking buttons on a post. At the white end of the scale, make sure you don't include any that will make you look unpopular. At the darker end of the scale, have a think about what might make you look more popular.

Tendency to balance options

Apparently people tend to balance options put in front of them - if you ask someone the proportion of their savings to put into stocks and the proportion into bonds (simplified example) they will tend to go for a 50:50 split, but if you instead ask the proportion to put into US stocks, UK stocks and bonds, they will tend to go for 1/3 in each. Weird huh?

Using this information

I think this has more applications on the business side of things. When you are discussing budgets, be aware that this is going on. For those who don't naturally allocate much to SEO, try to present it alongside a big budget item (such as design and development of a new site) rather than as one item among many (design, development, testing, PR, PPC etc.).

I'll end with a brief summary of when Nudges work best. They work least well when presented with a decision that we make regularly for small stakes and understand well (and where the reward / cost comes close to the point of decision). It's hard to Nudge someone to choose a flavour of ice cream they like less over one they like more. Nudges work best in the opposite case - decisions we make rarely for large stakes without understanding them well and where the benefits are not felt for some time after the decision point - this is when we don't get good / immediate feedback about our decisions (or don't get a chance to practice) and so we fall back more on our 'gut feeling' - which is very "nudgeable". Notice how much this sounds like the typical board / CEO making decisions about SEO spending!

As with so many things, Homer said it best (from p.140 of my copy of Nudge):

Canyonero salesman: Okay, here's how your lease breaks down. This is your down payment, then here's your monthly, annnnnnnnnd, there's your weekly.

Homer: And that's it, right?

Canyonero salesman: Yup.... oh, then after your final monthly payment there's the routine CBP, or Crippling Balloon Payment

Homer: But that's not for a while, right?

Canyonero salesman: Right!

Homer: Sweet!

I hope you've found this interesting. I was fascinated by the ways we all trade off non-economic things in our decision-making. I'd be interested in hearing others' examples in the comments below and also other applications of Nudges in SEO or CRO.

(*) note that I don't think anyone is these days claiming the early economic arguments that everything is evaluated in financial cost / benefit trade-off terms. Rather the argument goes that people have their own definitions of 'utility' which can change depending on mood, current situation etc. and that they generally act to maximise utility. What Nudge is saying is that you can even go beyond this and find differences in decision-making out of proportion to the utility differences (or even where there is no measurable difference in utility).