The personality quiz challenges me with an existential question: "Do you know who you really are?" I respond on a sliding scale (strongly disagree to strongly agree) to statements including "I believe in the importance of art", "I tend to vote for conservative political candidates" and "I know how to captivate people".

"Continue to your score," it says. But first I must log into Facebook or provide my name, gender, birth year, postal code and email. "We require your details to provide an accurate personality score."

Bits of me float off into cyberspace. But I don't give a thought to that because the quiz is now telling me who I really am. "Our psychologist says you're a Rebel," it says, and reveals I pursue intellectual and artistic activities, enjoy challenges and can be impulsive. It tells me where I sit on the OCEAN scale, a measure psychologists use to determine someone's Openness to experience, Conscientiousness, Extroversion, Agreeableness and Neuroticism. It tells me I'm high in neuroticism and low in agreeableness. I don't think the quiz really knows who I am at all.

When Alexander Nix took the quiz, the "psychologist" told him he was "a Champion", a highly aspirational problem-solver interested in unique and creative ideas. He is resilient, tenacious and able to cope well with setbacks, although he sometimes exerts negative behaviour in reaction to conflict. I think I see some of that behaviour when I meet Nix in a Sydney city hotel lobby. 

It is April, and he is trim in a dark suit. He has the fine, firm hands of an equestrian. But he quickly pulls his hand from the shake and returns it to his phone keypad. With square jaw and spectacles, slicked hair, and broad, unsmiling mouth, fleetingly he's Clark Kent. But Nix, the English CEO of UK data analytics and behavioural communications company Cambridge Analytica (CA), has no affinity with reporters.

I try small talk as we walk from lobby to mezzanine lounge. Nix does not respond. His attention is on his phone. He is a busy man who works with global CEOs and heads of state. Last year, Wired magazine dubbed him one of the "25 geniuses who are creating the future of business". He was in Trump Tower on the night of November 8, 2016, watching the US presidential election results with Donald Trump and his running-mate Mike Pence.

We find a table, wave away a waitress. I ask if I can record the interview. Yes, he says, but he'll record it, too. He has, he says, frequently been misquoted. He is brusque and cold. Nix blames "shoddy journalism" for some of the controversy surrounding Cambridge Analytica, which this year opened a Sydney office. While Nix and his CA colleague Matt Oczkowski have moved on this trip from a conference about big data to meetings with potential Australian business partners and clients, including politicians from the Coalition and the ALP, inconvenient headlines have hovered: "Shadowy Tech Firm that Helped Trump Win … ", "The Great British Brexit Robbery – How Our Democracy Was Hijacked", "The Data that Turned the World Upside Down".

For its business to be successful, Cambridge Analytica needs to know us. It needs to know our character so it can understand what we care about, what motivates us and what informs our decision-making. To that end, the company uses computer algorithms of ever-increasing sophistication to analyse masses of personal data combined with the results of psychographic tests into people's personality and attitudes, and research into their behaviour (drawn from quizzes such as the OCEAN test, or phone, online or face-to-face surveys). Then, CA divides audiences into segmented groups, delivering them hyper-personalised messages that have the potential to influence their political and consumer behaviour.

Nix shares little detail about the exact forms of these messages but at an online marketing conference in Hamburg in March, he boasted that the company spent more than $US100 million on data-driven digital advertising on behalf of the Trump campaign. It's likely that much of that was directed to Facebook, where advertisers can micro-target audiences. 

The company's political connections have fed the headlines. Steve Bannon was a CA board member until he became President Trump's chief advisor. In the past few months, articles in publications including the UK's Observer and Guardian have alleged links between CA and its right-wing American billionaire backer Robert Mercer, and far-right British politician Nigel Farage, the Leave.eu campaign and Brexit. Nix denies that CA worked on the Leave.eu campaign, and CA has threatened legal action against the Guardian Media Group over the stories. (In May, the UK Information Commissioner announced it would investigate the use of data analytics for political purposes, particularly those deployed during the EU referendum campaign. "Our contact with Cambridge Analytica remains ongoing," a commission spokesperson tells Good Weekend.)

When I emailed Cambridge Analytica's New York-based public relations company to request an interview with Nix, I'd explained I wanted to profile him. Little has been written about Nix as a character. "A polo-playing Old Etonian" is about all Google reveals. Yet he is, for better or worse, a man of our times. CA's work on the Trump campaign has focused attention on the opaque, tentacled and ballooning world of big data, which has profound implications for our consumer behaviour, society, privacy and ethical and political systems, and has created a new sphere of criminal activity.

"People are working out ways to monetise personal information and behaviours to sell to others," says Professor Dave Lacey, a cyber-security academic at Queensland's Sunshine Coast University and the managing director of IDCARE, Australia and New Zealand's National Identity and Cyber Support Service. Beyond that, says big data expert Vanessa Teague, an academic in the University of Melbourne's School of Computing and Information Systems, the industry uses "highly intimate" data to manipulate people politically. "It seems plausible that CA's efforts with individualised political advertising had a substantial effect on the outcome of [the election of] the most powerful person in the world," she says.

We have somewhere close to four or five thousand data points on every adult in the United States.

Alexander Nix

Nix didn't read the email I sent to his flacks. About 10 minutes into our interview, as I'm coaxing him to share stories about his London childhood and education, he pauses mid-answer. He's bristling and thinking hard. His jaw shifts almost imperceptibly from side to side. "I thought this was a business interview," he says. No, I say, and show him the original email I sent to his PR company. "I think I've wasted your time; I didn't read the information," he says, shifting in his seat as though to stand. "I'm quite a private person. I don't think it's necessarily in my best interests to share my life with other people. I'm sorry about that. But I'm just feeling uncomfortable about this. I don't think that I want to be the story."

Nix has frequently talked about the number of individual data-points Cambridge holds on people: factual, attitudinal and behavioural. "We have somewhere close to four or five thousand data points on every adult in the US," he told a summit in New York last year. 

Think about that for a moment: 5000 data-points on about 220 million Americans. Name, gender, birth year, postal code and email are just five items we all commonly supply. Nix claims CA has around 4995 other pieces of information about most American adults. Seemingly innocent personality tests assume more sinister qualities when you realise they are designed to harvest data. I point out to Nix the irony – that his business relies on a massive amount of information about other people yet he is unwilling to share his own. "But not intrusive information," he protests. " 'Will you eat Weetabix or Cornflakes for breakfast?' is hardly raking through someone's background."

I'VE BEEN TAKING other free personality tests. "Which animal's blood runs in your body?" asks one doing the rounds on Facebook. (Answer: "The warm blood of a tiger.") "Your friends have written your eulogy! Take a look now," suggests another. ("She is sunshine mixed with rain, creating a beautiful rainbow.") 

It's easy to think of such quizzes as just a bit of fun, a salve for our increasingly narcissistic souls, but David Watts, the Victorian Commissioner for Privacy and Data Protection, issues a warning: "If a service is free, you are the product; the service is just there to get your information. Nothing comes in life for free." 

To take those quizzes, I had to give Social Sweethearts, their Köln-based creator, access to my Facebook account. The Social Sweethearts' home page has sub-headings including "Make People Smile", "Data-Driven Approach", "Artificial Intelligence" and "Machine Learning". I request an interview with CEO Daniel Minini who, in an illustration on the homepage, resembles a young George Michael: smiling, affable, open. He's not open to an interview, though. 

"PR-Team Social Sweethearts" tells me to send my questions via email. "If you sign up to our service with Facebook Authentication we may only access data that is understood by Facebook as public information," is the reply to my question about what information the company takes from my Facebook page. The answers reassure me, to a point, that what can be scooped from my profile is dictated by the Facebook privacy settings I myself have put in place. "We can assure you: we don't sell user data!" says PR-Team Social Sweethearts.

For the purposes of this article, I take three other personality quizzes popular on Facebook, then email the companies behind them to try to learn where my data goes and what it's used for. One email bounces back. Two go unanswered. I will never know what was taken from me when I had some fun on Facebook. 

But kooky quizzes created by companies like Social Sweethearts, or ostensibly more serious personality tests such as the OCEAN version offered on Cambridge Analytica's website, are just one source of data. There are countless others being collected by any number of players, including government agencies and companies such as Experian, Acxiom and Nielsen. (Any company working in the sphere of big data would say they de-identify people's information). 

"Every time we do anything, we're contributing to this information out there," Dave Lacey says. I ask him about the scale of the industry but, down the phone line from Queensland, I sense him shaking his head. "It's like trying to nail jelly to a wall; you're trying to define a market that is indefinable," he says. Jodie Sangster, the CEO of the Association for Data-Driven Marketing & Advertising, offers nothing more concrete. "There are analytics companies, technology companies, consulting firms … it's just vast and there are a lot of people and businesses involved in the chain."

ALEXANDER NIX thaws somewhat as we move from his personal story to the subject of his data company. He says that, while Cambridge Analytica doesn't have databases on Australians, there's a "huge amount of data available in Australia that can be commercially acquired". It is enough, he says, for CA to be able to undertake work for Australian commercial and political clients. "We think this is a very exciting market because there's a huge economy ... but some of the technologies and methodologies we developed in the US and are prevalent there aren't yet available here, so if we can introduce those, there could be a lot of opportunity to help companies."

Cambridge Analytica mines data but CEO Alexander Nix doesn't like giving away much about himself. Photo: Getty Images

I'm still hoping that Nix will loosen up and divulge a little more personal data. I tell him about my rebellious OCEAN test results and inquire after his own. He can't remember what the "psychologist" said about him, he says, but he'll email his results when he gets back to his London office. Well, I press, what is your personality? Nix smiles for the first time. "Oh crumbs," he says. "I don't know. Oh, I couldn't possibly speculate."

NIX SHARES JUST A LITTLE MORE OF HIMSELF. He confirms that his full name is Alexander James Ashburner Nix. He is 42. He grew up in London's Notting Hill, and went to school at the ultra-exclusive Eton, where boys wear black tailcoats and white Eton collars to class. At Manchester University, he studied the history of art. 

"It was something that I always have been incredibly passionate about," says Nix, who is now a collector and patron; he supports the up-and-coming London artist Hormazd Narielwalla, who uses Savile Row tailors' discarded patterns as the foundation of his collages. "When I get spare time, I will frequently try to find a museum or a gallery." But it was never his intention to pursue a career in the art world. "I just thought this was the last opportunity to study something that I cared about. I was pretty adamant I'd go into finance."

After graduating, he spent some months in the Mexico City office of Baring Securities as a junior analyst. He had a year or two back in the UK in advertising, then time in Argentina with a business providing e-CRM (electronic customer relationship management) solutions. In 2000, in London again, he went into corporate finance, before joining Cambridge Analytica's affiliate British company, SCL Group, in 2003. 

He remains a director of SCL (Strategic Communications Laboratories). SCL, says Nix, is mainly focused on "government and defence work". Its projects have included assisting a client's counter-narcotics program by collecting population data in 13 Mexican cities under the influence of drug cartels; data collection about extremist recruitment across the south and south-east Pacific for a counterterrorism client; and data collection, analytics and strategy development "for the Ukrainian government in pursuit of their goal to win back control of Donetsk". (In March, SCL refuted media claims it had worked on military disinformation campaigns.)

CAMBRIDGE ANALYTICA was formed in 2013 as a vehicle for SCL to enter the US political market. (CA also works in other countries; Nix says that, every year, it contributes to seven or eight prime ministerial or presidential election campaigns in "well-established democracies".) Its US arrival coincided with reclusive hedge-fund tycoon Robert Mercer's increasing interest in politics. According to a New Yorker story in March, the libertarian decided to fund a big data project to focus on his political interests. He sank around $US5 million into Cambridge Analytica. The Mercers initially backed Ted Cruz's Republican presidential nomination and CA worked for that campaign until Cruz dropped out of the race in May, 2016. When the Mercers switched their support to Trump, Cambridge and Alexander Nix moved with them.

"We put an awful lot into that campaign," says Nix. According to US campaign finance data, the Trump campaign paid CA nearly $8 million in 2016. In Trump Tower on the night of November 8, the CA team ran complex statistical models as votes came in. "We had a pretty clear indication by Florida, which is about 8.30 in the evening, what was going to happen," says Nix. Around midnight, he left Trump Tower. First, he stopped by the Midtown Hilton Hotel where Republicans were celebrating at the official Trump election party. Then, at around 3am, he returned to CA's office and, with colleagues, downed Scotch and reflected on the campaign.

After assisting Donald Trump during his presidential campaign, Cambridge Analytica's Alexander Nix was among those who eagerly watched the results on election night last November.

"It was a tremendous experience to work on, be part of and ultimately win an election campaign of that magnitude," he says. But in the weeks following the election, as Nix enjoyed a polo-playing holiday in Argentina with his wife and three young children, commentators started to question whether CA's work had actually had any real impact on Trump's win, especially given that Hillary Clinton's campaign also deployed formidable data analytics operations. Many have dismissed psychographic data analytics such as those which Cambridge claims to use as "snake oil". 

Meanwhile, the extent to which psychographics were deployed in the campaign is unclear. At conferences in the past few months, Nix has talked about what CA had available for the Trump campaign – a "huge amount" of voter survey data, research and technological infrastructure – and "hundreds of thousands or millions of OCEAN profiles" the company had collected that enabled it to "form a model to predict the personality of every single adult in the United States of America". Yet, in a statement about the campaign, the company said: "Cambridge Analytica did not have the opportunity to dive deeply into our psychographic offering because we simply did not have the time."

In May, Hillary Clinton shared her thoughts on CA's contribution: "You can believe the hype on how great they were or the hype on how they weren't, but the fact is, they added something … They married content with delivery and data. And it was a potent combination."

AUSTRALIA'S PRIVACY AND DATA LAWS are stricter than those in the US, where individuals' data-points seem to bob about in an open market and so were able to be netted for Cambridge Analytica's work on the Trump campaign. Still, I want to know what data of mine is floating around in this world of "surveillance capitalism", a term coined by American author and retired academic Shoshana Zuboff. 

I consider my online activity: the cookies that track my clicks; my social media accounts – Instagram, Twitter and Facebook – plus the third-party apps Facebook hosts like those personality tests. I discover a free site called Stalkscan, which scrapes all the public information held on someone's Facebook account and aggregates it in one place, including everything they've ever "liked". I think about the apps on my phone – MyFitnessPal, RunKeeper and Sleep Cycle – which retain information about my health and wellbeing. And I think about Google, which knows more about us than our closest confidantes ever will and can blend a person's data from their activity on multiple Google products (from maps to search) to deliver ever more targeted advertising.

"Remember, Google's customers are advertisers, not users," says academic Vanessa Teague. "So the service to Google's customers is that they can get good data about how effective their ads are." (In June, Google announced it would no longer scan emails held in free Gmail accounts for the purposes of ad personalisation.) I dig through my wallet. I have debit and credit cards. "Every Australian who's ever applied for a bank loan, a credit card or a mobile phone would have a presence on a credit-reporting agency's systems," says Dave Lacey, of IDCARE. 

I have loyalty cards: Flybuys, Country Road, Sportscraft, Witchery, Jigsaw, Dan Murphy's, Hyatt and Wholefoods House. I apply to Sportscraft and Flybuys for a copy of the information they hold on me, as I'm entitled to do by law. Sportscraft has on record my name, email, address, age and transaction history. It knows when I've had to go up a size. Flybuys has my name, address, email, birthday, details of the rewards I have redeemed, details of when I've shopped, where I've shopped (including at partners such as Liquorland) and how much I've spent. Coles holds the information about my shopping trolley history.

I request an interview with Adam Story, Coles' general manager (Flybuys, loyalty and customer relationship management) but my request is denied. Evidently, Story doesn't want a relationship with every customer. In April, he sat on a data conference panel in Sydney with CA's Nix. "You need to make sure your marketing team can truly harness the data with always the customer's needs and expectations in mind," Story told the audience. "At Coles, our team has been trained to leverage the right tech platforms ... to deliver a truly personalised experience." 

I read the fine print: the Flybuys privacy policy. It's a grey zone that seems to allow for a great deal of leveraging, and a great deal of sharing: "To make it easy for you to deal with Participants and other Wesfarmers group companies (including Coles) and provide you with a more personal and consistent experience, we may exchange and combine personal information with them for the purposes described in our respective privacy policies … We and Wesfarmers group companies may exchange your personal information with service providers engaged to assist with services including data processing, data analysis, information broking…"

But as IDCARE's Dave Lacey says, "everyone's in this game". Woolworths has a stake in the data analytics firm Quantium, which has claimed to have datasets on 22.6 million Australians and "data and technology partnerships" with companies including Woolworths, NAB, Facebook and Foxtel (which explains why it says that, every day, it knows where 3.6-million remote-control clicks take Australian TV viewers). 

All of which might explain why Alexander Nix has so much confidence in the "huge amount" of data available in Australia for commercial acquisition. During interviews with subjects for this article, Experian, a global data and analytics company with offices in Sydney and Melbourne, is repeatedly mentioned as a data broker where CA might potentially do its shopping. Its corporate logo has appeared in Nix's conference presentations. It is also a major credit reporting agency.

I request an interview with an Experian executive. But in a surprise turn of events, my request is denied. No one wants to talk about big data. Instead, a PR firm emails me a statement: "Across the world Experian collects data from a range of sources to create marketing tools which our customers use to help target their communications in the most effective way. Wherever we operate, we act in strict accordance with the law and our own code of conduct. Today, we do not offer big data solutions to political parties in Australia and we do not have a commercial relationship with Cambridge Analytica." Not today, but what about tomorrow?

IT'S ONE THING FOR A PILE OF DATA to be gathered about me or you and crunched for the purposes of sending us micro-targeted advertising material designed to persuade us to buy a tube of advanced whitening toothpaste or a new car with a compact yet spacious interior. It's quite another when it can potentially shift election results. One night in April, Nix's colleague  Matt Oczkowski dined at the National Press Club in Canberra with a group of Coalition representatives. It was, says an insider, "a loose group of interested people", including at least one federal minister and several senior staff. It is believed that a group of Labor identities also met with Cambridge Analytica. But CA's representatives are not the only travelling salesmen to have visited Australia in the past few months.

"They've been all over us like a rash," says one Coalition figure, referring to the overseas data analysts, pollsters, strategists and researchers who have come touting for business during a sedentary phase of the American election cycle. "A lot of them are trying to wedge commercial work off perceived high-level political links," says another. (In an attempt to see what other work CA might have picked up here, I email the Australian office, registered at an address in Sydney, and request to speak with local boss Allan Lorraine, an "experienced automotive professional", according to his LinkedIn profile. No response. Later, Nix says Lorraine is just a consultant to the business and can't speak on its behalf.)

Those I talk with on both sides of politics, none of whom want to be named, are cynical about both how much Cambridge's offering contributed to Trump's success and its relevancy in Australia where, unlike in the US, voting is compulsory and a preferential system is in place. "There is a fair amount of puff in all of this activity," says one. Another tells me: "Somehow in the space of six months they turned themselves into a superstar machine, which I just don't buy." All point out that Australian political parties, to one degree or another, are already in the business of big data, using a combination of the electoral roll, focus group research, telephone surveys, polling and previous electoral results to build models of voters, what matters to them, and what their most persuadable issues are. 

Nix would argue that CA's expertise gives the company the capacity to dive even deeper. "It's all about understanding the motivations of the target audience and trying to understand at a very granular level why people might undertake a certain behaviour, whether that's joining a terrorist organisation or smoking cigarettes or eating fast food," says Nix. With that information, companies or political parties can micro-target segmented audiences with "addressable" ad technology – in Nix's words, "nuanced in order to reflect the way you see the world". Speaking at the Hamburg conference, Nix said: "Pretty much every message that Trump put out was data-driven."

But in the business of micro-targeting, there are bigger culprits than Cambridge Analytica. "What my research shows is that you can predict whether someone is liberal basically just by looking at the music they listen to, or the movies they watch, or the books they read," says Michael Kosinski, a global pioneer in psychometrics, the science of psychological measurement. Speaking from his office at Stanford University, he continues: "You don't even need to know those things because Google knows those things. So if I'm a politician I can go to Google and say, 'Please target people who recently searched for those 10 things.' On Facebook it's similar … you go to FB and say, 'Can you please send this message to people who do A, B, C and D.' "

I ask Melbourne academic Vanessa Teague about micro-targeting. "Yes, it just cuts out the noise of all the alternative viewpoints that would otherwise complicate a person's political decision-making," she says. "How sweet." Other experts have similar concerns. Suelette Dreyfus, a lecturer in the School of Computing and Information Systems at the University of Melbourne, believes the tools of the big data industry will help politicians to lie better. "It is a manipulation of the most extraordinarily customised nature."

In the Sydney hotel lobby, Nix protests the suggestion that CA's work of data gathering and information dissemination is subliminally manipulative. "All we're trying to do is to make sure that you receive the most relevant communications; if you care about the Second Amendment, why do you want to be bombarded with leaflets on pro-choice?" He doesn't resile from CA's contribution to the Trump campaign. "We're a service provider and we're just trying to provide the best possible service for our clients."

At the end of his address at the Hamburg conference, Nix took questions from a panel. One man, flushed in the face, said he had just one question. "If it's really true that you helped Trump get into office, are you happy putting a misogynist buffoon [into] the most powerful job in the world who's now f...ing up our world?" Nix answered the man's question calmly. It wasn't the role of people sitting in other countries to cast their opinions on what was a free and fair election or on the self-determination of the American people, he said.

As we wind up our interview, he tells me CA will be working on the US midterm elections in November next year. "It's going to be interesting to see how that's going to play out."

My time is up. Nix has shared little of his life and retained his privacy; I'm not sure if I've gained any sense at all about who he really is. In a cab returning to the office, I pull out my phone and open Facebook. I search to see if Alexander Nix has a profile. There's no sign of one. I look at my feed. Someone has posted a link to a personality quiz: "What do you see inside of the maze? This incredible test will reveal the secrets of your personality." I go to the drop-down menu and click the option, "Hide post: see fewer posts like this."  

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