The nudge that persuaded Aussies to stop speeding

Summary

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Nudge – “The Nudge that Persuaded Aussies to Stop Speeding”

Host: Phil Agnew
Guest: Adam Ferrier (Co-founder, Thinkerbell)
Date: December 22, 2025

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Overview: Main Theme & Purpose

This episode explores how psychological biases—especially the availability bias—were harnessed in a groundbreaking road safety campaign in Victoria, Australia. Host Phil Agnew and guest Adam Ferrier unpack the logic and effectiveness behind the “Australia’s Deadliest Predator” advert, which reframed how Aussies think about the dangers of speeding. The conversation delves into the science of memorable messaging, behavioral change, and the importance of engaging audiences, offering powerful lessons for marketers and behavioral scientists alike.

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Key Discussion Points & Insights

1. The Availability Bias and Public Perception

• Availability bias: People estimate the likelihood of events based on how easily examples come to mind. We often overrate risks that are vivid (like shark attacks), and underrate more common but less dramatic dangers (like car accidents).
  • Phil (00:26): “We create a picture of the world using examples that come most easily to mind.”
  • This bias shapes public attitudes toward dangers in Australia—sharks, snakes, and spiders are considered lethal, while common threats like speeding are minimized.

2. Adam Ferrier’s Background & Approach

• Adam’s intro: Consumer psychologist, co-founder of Thinkerbell, focused on blending marketing science with creativity (“measured magic”).
  • Adam (02:09): “Thinkerbell’s purpose is to unleash measured magic into the world to keep things interesting.”
• Psychological insights fuel his campaigns.

3. The Evolution of Road Safety Campaigns in Victoria

• Victoria’s Traffic Accident Commission has a history of impactful, emotional ads—most famously the “Drunk Driving: Bloody Idiot” campaign, which used vivid hospital scenes.
  • Phil (04:23): “Road deaths dropped 37% in the 12 months following this campaign.”
• While drunk driving became socially unacceptable, low-level speeding did not; inertia and misperceived risk kept it normalized.

4. The “Australia’s Deadliest Predator” Campaign: Creative Strategy

• New campaign set out to shift perceptions, using people’s overestimation of animal dangers to highlight the overlooked risk of speeding.
  • The ad presents a suspenseful question: “What is Australia’s deadliest predator?” (06:34)
  • Reveal: Headlights of a car mimic predator eyes, flipping expectations.
• Audio-only variants used animal sounds that were revealed as actually being car crashes, further tricking listeners with their own bias.
  • Adam (07:17): “The reason why this works… we remember stuff that’s more vivid and more front of mind… So if you ask people what's dangerous, they're much more likely to say something that's vivid…”
  • Phil (08:19): “This mismatch between expectations and reality doesn’t just happen with car accidents and shark attacks…”

5. Engaging Audiences: Reactance & the Generation Effect

• Instead of ordering people not to speed, the ad asks an open question, inviting engagement and self-discovery.
  • Phil (10:25): “It doesn’t explicitly tell people not to speed. It asks them, what's Australia’s deadliest predator?”
  • Adam (10:52): “Allow them in, allow them to join the dots. And by directly asking a question, it allows them to do that also.”
  • Emphasizes “leaving room” for the consumer in the communication.
• This taps the generation effect (making people work out the answer for themselves enhances memorability).
  • Phil (13:43): “Forcing the audience to engage and think about the ad… probably made the ad more effective.”

6. Results & Behavioral Impact

• Immediate results: Post-exposure surveys showed 90% positive sentiment, with increased perception of the risks of low-level speeding.
  • Adam (15:08): “There was a 90% positive sentiment… encouraging people to consider low-level driving as being more risky than before.”
• Ultimate goal: Shift social norms, making speeding less acceptable—though hard data on behavior change wasn’t isolated.

7. Broader Lessons & Applications

• The availability bias drives misjudgment across contexts (e.g., more Americans died in car crashes after 9/11 due to fear of flying—08:19).
• Generation effect in other campaigns: UK Blood Service removed “O”s from ads to stress blood type shortages; Specsavers ads use purposeful mistakes to engage viewers.

8. Entertaining Example: Derren Brown and Availability Bias

• Derren Brown’s trick (16:00): Via subtle wordplay (“bike gifts,” “handlebar,” “saddle”), Brown influences Simon Pegg to want a BMX bike for his birthday, making the idea highly “available” in Pegg’s mind.
  • Phil (18:02): “By using this word, he is putting the bike to the front of his mind… because of the availability bias, he makes Simon Pegg more likely to choose it.”

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Notable Quotes & Memorable Moments

• Phil Agnew (00:26): “There are more than twice as many words that have K in the third position than start with the letter K. So why do we all get this wrong?… It’s known as the availability bias.”
• Adam Ferrier (05:14): “One of the reasons [low-level speeding is perceived as less dangerous] is people just don’t think it’s that dangerous… They’ll overrate [animal dangers] as being much more likely… than being involved in a fatality with a car.”
• Adam Ferrier (07:17): “We remember stuff that’s more vivid… if you ask people what's dangerous, they're much more likely to say something that's vivid in the mind, like a shark… When I think of something dangerous, the first thing that pops into my head is a shark or a snake… not a Commodore being driven by a person.”
• Adam Ferrier (10:52): “By directly asking a question, it allows them to do that also. We’re not necessarily straight out giving the answer… the reveal is right at the end and then they can go, ‘oh shit, yeah, okay, I get it, I see what you’ve done there.’”
• Phil Agnew (13:43): “Forcing the audience to engage and think about the ad… probably made the ad more effective.”
• Adam Ferrier (15:08): “There was a 90% positive sentiment encouraging people to consider low-level driving as being more risky than before.”
• Phil Agnew (18:02): ”By using this word he is putting the bike to the front of his mind. He is making it available…”

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Important Timestamps

• 00:00 – Phil’s opening quiz about the availability bias
• 02:00 – Adam Ferrier’s intro and background
• 03:02 – History of Victoria’s road safety ads
• 05:14 – Explanation of misjudged dangers & introduction of “Australia’s Deadliest Predator”
• 06:34 – The campaign’s suspenseful predator voiceover
• 07:01 – The reveal: speeding cars as true “predator”
• 10:25 – Discussion on nudges versus explicit instructions; the importance of questions
• 13:43 – Generation effect and campaign memorability
• 15:08 – Results: attitude shift evidenced by survey
• 16:00 – Story: Derren Brown, Simon Pegg, and the availability bias in action

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Conclusion

Through an in-depth conversation and illustrative examples, this episode highlights how cognitive biases can be consciously and creatively leveraged in public campaigns. The “Australia’s Deadliest Predator” initiative cleverly recast speeding as the real killer, changing perceptions by making the threat more memorable and vivid. Listeners walk away with actionable behavioral science lessons—illuminating the intersections of emotion, bias, and thoughtful marketing.

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Transcript

[Phil Agnew]

Lets start today's episode with a quiz question. Are there more words in the English language that start with the letter K? Or are there more words in the English language with K as their third letter? So, starting with K or K as the third letter, I'll give you a few seconds to think. Now, chances are you think there are more words than that starts with the letter K. That is what most people think when they are asked this question. But the opposite is true. There are more than twice as many words that have K in the third position. Then start with the letter K. So why do we all get this wrong? Well, according to Rolf Dobelli, it's because we can quickly think of words beginning with K far more quickly. They are more available to our memory and this is known as the availability bias. Dobelli writes how we create a picture of the world using examples that come most easily to mind. This is absurd, of course, because in reality things don't happen more frequently just because we can conceive of them easily. I've known about this bias for a while, but I've never seen it used in an advert. Especially not an advert like this.

[Narrator/Ad Voice]

What is Australia's deadliest predator?

[Phil Agnew]

Learn about the nudge that persuaded Australians to stop speeding after this short break. Being a know it all used to be considered a bad thing, but in business, it's everything. Because right now most businesses only use 20% of their data. Unless you have HubSpot. HubSpot transforms data that is buried in emails, call logs and meeting notes into insights that can help grow your business. Because when you know more, you grow more. And I think that's an example where being a know it all isn't so bad at all. Visit HubSpot.com today to learn more. Hello and welcome to Nudge. Now, I had never seen the availability bias used in an ad before, but today's guest on the show has.

[Adam Ferrier]

I'm Adam Ferrier. I'm a consumer psychologist and co founder of a creative company called Thinkerbell.

[Phil Agnew]

Adam's known about the availability bias for years.

[Adam Ferrier]

I studied psychology and commerce at university and then did my master's in clinical psychology on identifying the underlying constructs of cool people. I started my career in the prison system, became a cool hun, then went to Satchi and Saatchi for a year, then started Naked Communications in the APAC region, sold that and then started Thinkerbell about eight years ago. Thinkerbell's got about 200 people. We practice what we call measured magic, which is marketing sciences meets Hardcore creativity. And our purpose is to unleash measured magic into the world to keep things interesting.

[Phil Agnew]

What I love about Adam is that he uses his background in psychology to inspire his work in marketing. He's always looking for interesting biases and nudges that he can use to improve a campaign. So when the state of Victoria came to Adam asking him to help reduce the number of car crashes, Adam came up with a fairly novel idea.

[Adam Ferrier]

Sure. So the tic is the Traffic Accident Commission which looks after road safety for the state of Victoria in Australia. They've had a history of doing kind of big beer appeal type advertising for a long time and then highly emotive evocative campaigns and lots of kind of award winning and very effective work over the years. Much of their work has been around drunk driving and they had a particular famous campaign many years ago he called in Australia, which was Drunk Driving Bloody idiot.

[Phil Agnew]

Their first ad released back in the 80s, shows exactly what happens in a hospital following a drunk driver collision.

[Actor in Drunk Driving Ad]

It's not just the physical injuries, you have to learn to cope with that. It's the sheer waste and the stench of alcohol that stays with you. I'm just going to inform you that your daughter Lucy has been involved in a car accident.

[Derren Brown]

Do you want to come with us? We'll just have a chat to you for a second. She's okay. Her left leg been damaged quite severely. There's a possibility that she may lose that leg.

[Adam Ferrier]

We'll also scan her head to look.

[Derren Brown]

At whether there's any head injury as well.

[Actor in Drunk Driving Ad]

They drink too much and then they drive, they smash up their cars and the people they're supposed to care about and if they survive, they're the ones that have to live with that. And that's the real tragedy. If you drink, then drive, you're a bloody idiot.

[Phil Agnew]

It's visceral, it's emotive and it was highly effective. Road deaths dropped 37% in the 12 months following this campaign.

[Adam Ferrier]

Over that time, drunk driving has become completely socially unacceptable, yet low level speeding hasn't. And so low level speeding now accounts for about 30% of all fatalities. And it's become quite an issue for the TAC to tackle. One of the reasons is people just don't think it's that dangerous. And so when you ask people how dangerous is low level speeding, they'll say, you know, it's not that dangerous at all. Yet if you ask them, you know, how dangerous is it to swim in the water or how lucky is it you're going to get eaten by a shark or bitten by a spider or bitten by a snake. They'll overrate that as being much more dangerous and much more likely to happen than it is being involved in a, in a fatality with a car.

[Phil Agnew]

We overestimate the deadliness of animals because of this availability bias. It's easy to conjure up images of a killer shark, but not as easy to conjure up an image of a car accident at 30 miles an hour. Stuart Sutherland highlights this in his book Irrationality. He cites the movie Jaws with its man eating shark, and notes that after the film aired, there was a sharp drop in the number of swimmers off the coast of California where the occasional shark is found to be near the beaches. However, he goes on to write that it has been calculated that the risk of swimmers being snapped up by a shark is very much less than the risk of them being killed in a road accident while on their way to the beach. So Adam wanted to use this strong bias, this availability bias in his campaign.

[Adam Ferrier]

We wanted to kind of tackle this. And so we did a campaign called Australia's Greatest Predator, which kind of paralleled driving in a speeding car being much more dangerous than a shark or a spider or any other kind of predator in Australia. So that's what we did. So the actual campaign, across a whole lot of different mediums, brought to life various predators in kind of dangerous looking ways and then asked people to kind of guess what Australia's most dangerous predator was.

[Narrator/Ad Voice]

What is Australia's deadliest predator? The one that hits with more than 30 GS of force, strikes in under a second, leaves catastrophic injury in its wake. You won't hear it, you won't see it, not until it's too late. Australia's deadliest predator isn't found in the wild. It's on our robes. Speeding is the killer.

[Adam Ferrier]

And then in the end of the the reveal was the headlights looking like the eyes of a very dangerous predator, but they're the headlights of a speeding car. And then we revealed that no, it wasn't any of these things, it was a speeding car.

[Phil Agnew]

And this ad plays on the availability bias.

[Adam Ferrier]

The reason why this works so well is it tackles what psychologists call the availability bias. And the availability bias is basically we remember stuff that's more vivid and more front of mind rather than we do what's potentially true. So in this case, if you ask people what's dangerous, they're much more likely to say something that's vivid in the mind, like a shark or a snake or something, rather than a speeding car. And that's because we've been kind of growing up to kind of see these things, these, these images as being very closely associated with danger. So we've grown up to learn to avoid snakes, avoid sharks. They've got very, very graphic imagery and so on. When I think of something dangerous, the first thing that pops into my head is a shark or a snake or a dangerous spider. The first thing that pops into my head is not a Commodore being driven by a person or a speeding car. So we wanted to kind of tackle that and parallel a speeding car with one of these other things that pops straight into the mind when you think of something dangerous.

[Phil Agnew]

This mismatch between expectations and reality doesn't just happen with car accidents and shark attacks. Previous guest on Nudge, Professor Gert Gigerenza investigated changes of behaviour induced in the wake of the 911 attacks. In the 12 months after the attacks, US passenger air miles fell between 20 to 12% as people switched their means of transport for long distance journeys from planes to cars. The issue with a switch like this is, relatively speaking, mile for mile, air travel is far safer than travelling by road. A decision described by Gerd Gigerenter as jumping from the frying pan into the fire. Using road traffic defs data coupled with the air figures, he estimated that an extra 1,595Americans died in road traffic accidents due to the switch. Cialdini writes that the response is consistent with the availability bias. In the immediate aftermath of the attack, the stark, terrifying prospect of a terrorist hijack was fresh in the mind of the American public. Americans consequently overestimated the risk of hijack and chose another, but a riskier form of transport. In irrationality. Sutherland writes how in one study it was found that people think they are twice as likely to to die of an accident as from a stroke. In fact, people are 40 times more likely to die of a stroke than from an accident. The reason for this false belief is that although most people die in their beds, air crashes and violence are constantly reported in the media and are highly dramatic and therefore they are available.

[Adam Ferrier]

So when you normally think of a deadly predator, you're normally thinking of a shark or a snake. If I said to you, what's Australia's most deadly predator? They're the things that pop into your mind, but in fact, a spinning car is much more deadly, deadly than a snake. And so by putting it into that context, it's a very, very different conversation that suddenly makes it much more vivid and makes the danger seem much more real. And once we've done that, then it allows the person to kind of have their own internal dialogue and think, oh shit, Raoul, that really is more dangerous.

[Phil Agnew]

In my last episode with Adam titled Don't Listen to this Podcast, Adam explained how if an ad tells the viewer to explicitly do something, they're less likely to do it. This is down to reactance, a feeling of unpleasantness and resistance when we think our autonomy is challenged. What I love about the Deadliest Predator campaign is it does the same thing. It doesn't explicitly tell people not to speed. It asks them a what's Australia's deadliest predator?

[Adam Ferrier]

We talk about leaving a little bit of room for the consumer in our communication. So allow them in, allow them to join the dots. And by directly asking a question, it allows them to do that also. We're not necessarily straight out giving the answer. We're kind of engaging them in a bit of a narrative. In the communications, there's various ways of doing that. One of them is asking them to guess along the way. And then we're showing various lights of various deadly predators before showing the headlights of a car. And so the reveal is right at the end and then they can go, oh shit, yeah, okay, I get it, I see what you've done there. But they're in. They're part of the communications. It's not just being forced on them.

[Phil Agnew]

This was especially true for the audio only version of the ad.

[Adam Ferrier]

And then the other, the other way we've done it, as well as just having an audio experience where you're listening to all of these different kind of what you think are car sounds or car crashes, but they're all sounds made up of various deadly animals.

[Narrator/Ad Voice]

What is Australia's Deadliest Predator?

[Adam Ferrier]

And again, the reveal is that all those sounds you've heard thinking that they're just car crashes, are actually the sounds of deadly predators in the Australian landscape.

[Narrator/Ad Voice]

Every sound you've just heard is from Australia's deadliest predator, speeding.

[Phil Agnew]

But what were the results of this campaign? How else has this bias been used? And is it really true that hypnotists can use this bias to influence people? Well, find out after this quick break. The Next Wave, your Chief AI Officer, hosted by Matt Wolfe and Nathan Land, is brought to you by the HubSpot Podcast Network, the audio destination for business professionals. Listen and you'll hear from leading AI creators who are your guiding light in the AI and technology frontier. AI technology is transforming the way we do business and the media landscape is fragmented. The Next Wave strives to be the leading podcast on AI technology and how you can apply it to growing your business. Listen to the next wave wherever you get your podcasts. Hello, welcome back. You are listening to Nudge with me, Phil Agnew. Now, Adam's ad was clearly inspired by the availability bias. But as he talked me through it, I wondered if it also benefited from another bias. It's a bias I've spoken about before on the show and it's known as the generation effect. I first read about this effect in Richard Shotton's great book, the Illusion of choice. In 2020, Shotton asked 415 people to read the names of brands in five cars, banks, beauty, supermarkets and electronics. Now, some people were showing the whole brand name, for example, the bank hsbc, whereas others were shown the same brand but with a letter missing, so the bank would be spelt H, B C. Later, he asked the participants which of the brands they could remember seeing. Turns out having that letter missing made the brand 14% more memorable. Like Adam's been saying, forcing the audience to engage and think about the ad to question what Australia's deadliest predator might be probably made the ad more effective.

[Adam Ferrier]

Possibly the best example of that I've ever seen was blood. I think it's a UK example initially where the blood service removed all the O's from the letters of their advertising and they said, we're running out of O type blood. So that, so all the, all the letters of the O's were removed and people had to work that out for themselves.

[Phil Agnew]

Getting your audience to think really does seem to work.

[Adam Ferrier]

And so, you know, like Specsavers, I've done a whole series of ads where they specifically, they're purposely mistaken. So I should have gone to Spec Savers and I said, welcome to Melbourne outside Sydney airport. And they said, welcome to Sydney outside Melbourne airport. They're in on the joke kind of thing. And these purposeful mistakes that people meant to spot and putting ads in was mistakes. And I'm saying, can you spot the ads? And so forth.

[Phil Agnew]

So back to the tac. Did this Australia's deadliest predator campaign work? Did the availability bias and generation effect actually change the way people drove?

[Adam Ferrier]

So the TIC have got a macro towards zero target and they've got a macro behavior change program. So this is kind of just one part of everything that they're doing. We did some post exposure questionnaires with people and kind of try to understand what their sentiment was to the campaign. There was a 90% positive sentiment encouraged, encouraging people to consider low level driving as being more risky than Before, So people saying, yes, I would. This has made me think about low level speeding in a different way. So it's also then therefore contributing to making speeding less socially acceptable, which is kind of one, one of the things which we needed to do. We haven't been able to isolate the direct contribution that's got on behavior change. That wasn't. It wasn't set up with that kind of experiment in mind. But you know, we think it will contribute.

[Phil Agnew]

It's hard to get firm results on a huge behavioural change campaign like this. But if scientific evidence behind the availability bias and generation effect is anything to go by, then this should work. And I'm pretty sure it works because I've seen a hypnotist use it. Derren Brown, the world famous British showman, used the availability bias on the Hollywood actor Simon Pegg. In his show, which I'll play a recording of in a bit, Derren asks Simon Pegg who what he would like for his birthday and using what he called hypnosis, makes Simon desire a gift that he didn't really want. Here's the clip.

[Derren Brown]

Okay. And also very nice to meet you and thank you for coming on the show. Let me explain to you how I buy gifts or presents for people.

[Adam Ferrier]

All right?

[Derren Brown]

And this is the best way to handle, bar none, the problem of you know, what to saddle for. When you're going to buy gifts for somebody that's a little bit difficult to buy for. Alright? Now what I do is rather than recycle the same sort of two tired bottles of wine or box of chocolates which are no fun to receive, I go out and I buy anything and then I make that person fall in love with it.

[Phil Agnew]

But does it work? Good.

[Derren Brown]

So you can have anything you like. What's your dream present?

[Adam Ferrier]

The BMX bike.

[Derren Brown]

A BMX bike?

[Narrator/Ad Voice]

Yeah.

[Derren Brown]

That'd be fantastic. And that would make you feel great, wouldn't it?

[Phil Agnew]

It will fulfill a childhood dream.

[Adam Ferrier]

Really?

[Derren Brown]

Is it a childhood dream to have one you never got on when you were a kid? So it'd be great to have one. Okay. Do you want to have a look?

[Phil Agnew]

Yes. Yes. Excellent.

[Derren Brown]

Come and have a look. What color? What did you have in mind?

[Phil Agnew]

Red.

[Adam Ferrier]

Red? Yeah. Have a look.

[Phil Agnew]

Waiting for Simon Peg under some wrapping paper in the corner of the room the whole time is a red BMX bike. So how did Derren make Simon desire this bike? Well, he used the availability bias. Included in his little spiel were dozens of words relating to a bike.

[Derren Brown]

So if you found yourself wanting a BMX2 this is probably why. Very nice to meet you and thank you for coming on the show. Let me explain to you how I bike gifts.

[Phil Agnew]

He said how I bike gifts and.

[Derren Brown]

This is the best way to handle, bar none. The problem of you know, what to saddle for when you're going to buy gifts for somebody that's a little bit difficult to buy for. All right now what I do is rather than recycle the same sort of.

[Phil Agnew]

Too tired bottles of wine, handlebar, saddle, cycle, too tired. By using this word, he is putting the bike to the front of his mind. He is making it available and because of the availability bias, he makes Simon Pegg more likely to choose it. Now, I don't think this trick will work for you if you buy your partner some crap present for Christmas. I think it can only be used by a professional like Derren Brown. You definitely have to be a professional to use this. But at least the availability of bias explains how it works. It's an incredible effect. It seems to be one that is prevalent in all sorts of walks of life. And I think it also explains how Adam persuaded Australians to stop speeding. All right, folks, that is all for today's episode of Nudge. However, Adam and I, we didn't finish chatting there. We went on to chat about how Adam teaches his team, his team of 200 people, behavioural science, what he looks for when he's hiring behavioural science minded staff for his agency, and how to run an organization with behavioural science at its heart. It was a really interesting chat. I'd never spoken to someone who really is invested in behavioural science as much as Adam and his organisation. Now, we knew this episode wouldn't be for everyone, so we made it available as a bonus episode. So if you've enjoyed today's show and you want more from Adam, you want to know how he runs this behavioral science agency, then all you have to do is go and download the bonus episode. To do that, just click the link in the show notes, enter your email address and you'll be taken straight to the bonus episode. If you're already a Nudge newsletter subscriber, then you already have the bonus episode. Just click the link in the PS of today's announcement email and you'll be taken right to. So for the bonus episode, if you want to listen, go to the show notes, click the link, enter your email and you'll be taken straight to the episode. You'll learn exactly how Adam organizes, hires and runs his behavioral science organization. That's all from me, folks. I've been your host, Phil Agnew. And I'll be back next Monday for another episode of Nudge Cheers.