What it means to be a pro

I just love this quote which uses a Tiger Woods anecdote to illustrate what it means to be a professional. It’s from The War of Art by Steven Pressfield (a great read, btw).

With four holes to go on the final day of the 2001 Masters (which Tiger went on to win, completing the all-four-majors-at-one-time Slam), some chucklehead in the gallery snapped a camera shutter at the top of Tiger’s backswing. Incredibly, Tiger was able to pull up in mid-swing and back off the shot. But that wasn’t the amazing part. After looking daggers at the malefactor, Tiger recomposed himself, stepped back to the ball, and striped it 310 down the middle.
That’s a professional. It is tough-mindedness at a level most of us can’t comprehend, let alone emulate. But let’s look more closely at what Tiger did, or rather what he didn’t do.
First, he didn’t react reflexively. He didn’t allow an act that by all rights should have provoked an automatic response of rage to actually produce that rage. He controlled his reaction. He governed his emotion.
Second, he didn’t take it personally. He could have perceived this shutterbug’s act as a deliberate blow aimed at him individually, with the intention of throwing him off his shot. He could have reacted with outrage or indignation or cast himself as a victim. He didn’t.
Third, he didn’t take it as a sign of heaven’s malevolence. He could have experienced this bolt as the malice of the golfing gods, like a bad hop in baseball or a linesman’s miscall in tennis. He could have groaned or sulked or surrendered mentally to this injustice, this interference, and used it as an excuse to fail. He didn’t.
What he did do was maintain his sovereignty over the moment. He understood that, no matter what blow had befallen him from an outside agency, he himself still had his job to do, the shot he needed to hit right here, right now. And he knew that it remained within his power to produce that shot. Nothing stood in his way except whatever emotional upset he himself chose to hold on to.
That’s something to aspire to.

Visitors this month

This month we have a two excellent of long-term visitors in the group.

Visiting all month is Ivan Brugere a graduate from Tanya Berger-Wolff‘s group at University of Illinois, Chicago. Ivan is interested in Spatiotemporal network mining, Network inference and prediction, and Social network privacy modeling.

Stopping by between April 12th and April 18th is Laura Allesandretti, who’s a graduate student with Andrea Baronchelli at City University London. Laura, Andrea and I are studying the long-term changes in individual and collective mobility patterns. In the literature, human mobility is typically described on a meta-stable time-scale, where mobility is characterized by regular patterns. We are interested in how this meta-stable regime evolves over long stretches of time (years).


Ivan & Laura will both be giving talks during their visits, so stay tuned for more info.

Petter Holme

Emphasizing our focus on temporal networks, I am happy to announce that temporal networks czar,  Petter Holme will visit the lab on Feb 18th. Petter is the author (with Jari Saramäki, who visited last week) of the recent  & excellent review on temporal networks.

He will be giving giving an talk, and if you’re in the neighborhood, I highly recommend attending.

  • Speaker: Petter Holme. Associate Professor. Department of Energy Science. Sungkyunkwan University, Suwon Korea
  • Date. Feburary 18th, 2015
  • Time. 14:00
  • Location. DTU, Building 321, room 134
  • Title: Temporal networks of human interaction

Abstract: Since the turn of the millennium, networks have become a universal paradigm for simplifying large-scale complex systems, and for studying their system-wide functionalities. At the same time, there is considerable evidence that temporal structures, such as the burst-like behavior of human activity, affect dynamic systems on the network. These two lines of research come together in the study of temporal networks. Over the last five years, there has been a growing interest in how to analyze and model datasets in which we not only know which units interact (like in a traditional, static network), but also when the interactions take place. Just like static network analysis, the development of temporal network theory has been accelerated by the availability of new datasets. It should be noted that temporal networks are more than just extensions of static networks—they are e.g. (unlike simple, directed, weighted and multiplex networks) not transitive. In other words, if A and B are connected, and B and C are also connected, this does not imply that A and C are connected. Perhaps for this reason, temporal network theory has focused less on structural measures and studies of simple evolutionary models, and more on randomization studies and the simulation of spreading on empirical data. I will describe the state of the field, my own contributions (mostly about how temporal contact patterns affect infectious disease spreading), and discuss some future challenges.

Privacy Part II: Some examples of why privacy is important.

[This is part II of a series, you can find an overview here]

There are many reasons why privacy is important. I will not try to cover them all here, but instead I have chosen two central topics, which I find particularly important.

“I have nothing to hide, so why should I care?”

This one is a classic retort against privacy advocates. It has been used by Google’s then-CEO Eric Schmidt, who famously noted “If you have something that you don’t want anyone to know, maybe you shouldn’t be doing it in the first place” during a TV interview. And on the surface, it looks like a pretty good one (one that I might have used a few years ago).

Keeping private does not imply wrongdoing

There are many reasons why the nothing-to-hide stance is problematic. To me, the central reason is that it pre-supposes that things we want to keep private are “secrets”, the argument insinuates that a kind of wrongdoing is taking place whenever we want to keep something to ourselves.

But imagine that you have just found out you and your significant other are pregnant. Maybe that’s a piece of information that you would like to wait approximately 12 weeks before you share with the world? And maybe you would want to tell your close family before before announcing the news to a broader circle of friends? On a less cheery note, you might want to control how your surroundings learn about other big personal events, for example a serious disease, such as cancer. As another example consider someone who just fell in love. Not being able to control who knows about your deepest feelings could potentially be deeply embarrassing.

These are not exactly dark secrets – just personal issues. But something that most people can understand, why we’d like to keep private.

Personal freedom is restricted

More generally, a world where all of your actions are known to everyone, becomes a world where personal freedom is restricted. I feel like I’m already experiencing this on e.g. Facebook, it looks like many present a curated, version of reality to the world, focusing mostly on positive aspects of their life (think photos of cute kids + delicious meals), while ignoring moments of doubt and insecurity. On Twitter, I know that what I say is persistent, so I usually avoid saying anything negative. In writing this post, I searched for “US torture war on terror” on Google and wondered if that would put me on som kind of watch list.

Because there is a multitude of things that are completely legitimate, but that we might not want to share with everyone – we risk inhibiting ourselves whenever one of those topic come up in a “persistent medium”.  That also means that your freedom is particularly reduced if your personal preferences do not line up completely with main-stream social norms. For example, in a world where every action is know to everyone, young gay or transgender people might have a difficult time finding themselves (= even more difficult than now).

Nothing-to-hide and the government

“Trust is good, but control is better”, as Lenin probably said. If a government systematically collects data on its citizens, the nothing-to-hide discussion finds new nuances.

Private information can be used as a means of control (e.g. via blackmail). Now, if your opponent has lots of ressources as well as access to a powerful legal system, this type of control  is not limited to individuals with “something to hide”. There are some great quotes on this. Bruce Schneier points to  Cardinal Richelieu who said “If one would give me six lines written by the hand of the most honest man, I would find something in them to have him hanged.” The russian dissident Aleksandr Solzhenitsyn said “Everyone is guilty of something or has something to conceal. All one has to do is look hard enough to find what it is”.

I tend to trust my government, so I’m not too worried about being blackmailed. As a pretty main-stream person, that’s probably a good assessment of my situation. But what if you’re in a minority? The United States has tortured innocent people  as part of the war on terror. Homosexual acts were illegal in the UK until 1967, and it can be argued that racial segregation in the US persists in varying degrees to the present day. Additionally, much of the world is run by governments that are not democratic and whose choices and inner workings are not transparent to their citizens.

Finally, even if you truly feel like sharing everything, there is a strong argument that as a society we want some people to have secrets. We want a free press with journalists that can protect their sources. Protected sources give citizens access to parts of society that we can otherwise never access – the criminal world – or inside governments.

The future: loss of self

There is another argument for privacy. It’s a a little more out here, but still central to the debate. The essence of the argument is that data collected about individuals can be used for other kinds of control than simply using blackmail. The next level is individualized manipulation.

In order to get that part up and running, recall that there has been some very interesting developments in the behavioral science, such as cognitive psychology, social psychology, behavioral economy, etc. The term that embodies all of these developments is nudging. The general idea is that, during human evolution, our brain has developed to make very quick decisions in a world that looks very different from our modern surroundings. Because of the need for milli-second speed, many of our decisions are not based on rational chains of thought, but on built-in heuristics. If you have a few hours to kill, check out of this list of known cognitive biases. Nudging is essentially the practice of “hacking” these heuristics to manipulate human behavior – and can be used as a force for good (e.g. to recycle or promote saving for retirement) or in more questionable ways (e.g. to sell us stuff).

One can imagine that data mining of personal data can be used to create personalized nudges. This is already happening to some extent – for example people with macs are steered towards more expensive hotel rooms than windows users on some sites.

Clearly, humans have always been manipulating each other – just think back to last time you purchased a car. But algorithmic nudging is different. In part because it runs at scale, with a single company potentially reaching hundreds of millions of users, and in part because the nudging potentially can be much more precise and effective.

We’re not there yet, but the long term perspectives are terrifying. In a fascinating piece in the New York Times called “Privacy and the Threat to the Self“, the philosopher Michael P. Lynch makes the case that complete loss of privacy effectively dehumanizes us and takes away our “self”. He writes:

To get a sense of what I mean, imagine that I could telepathically read all your conscious and unconscious thoughts and feelings — I could know about them in as much detail as you know about them yourself — and further, that you could not, in any way, control my access. You don’t, in other words, share your thoughts with me; I take them. The power I would have over you would of course be immense. Not only could you not hide from me, I would know instantly a great amount about how the outside world affects you, what scares you, what makes you act in the ways you do.  And that means I could not only know what you think, I could to a large extent control what you do.

Here, Lynch – from another vantage point – discusses what we have covered above. The fact that knowing about people allow you to control them. But we begin to see that it’s not just about blackmail, but also about manipulation. That’s where the personalize nudging comes in. Knowing enough allows you to accurately “read people’s mind” or at least anticipate their actions. He continues to say:

That is the political worry about the loss of privacy: it threatens  a loss of freedom. And the worry, of course, is not merely theoretical. Targeted ad programs, like Google’s, which track your Internet searches for the purpose of sending you ads that reflect your interests can create deeply complex psychological profiles — especially when one conducts searches for emotional or personal advice information: Am I gay? What is terrorism? What is atheism? If the government or some entity should request the identity of the person making these searches for national security purposes, we’d be on the way to having a real-world version of our thought experiment.

In the second paragraph, Lynch discusses another point that I have touched upon above. Surveillance is already happening. And the quote contains nice examples of how our online behavior may reveal lots of information about us, which is private in the sense that we might not want to share with everyone, but not something which implies any kind of wrongdoing. The final paragraph goes into why all this implies a loss of self:

But the loss of privacy doesn’t just threaten political freedom. Return for a moment to our thought experiment where I telepathically know all your thoughts whether you like it or not From my perspective, the perspective of the knower — your existence as a distinct person would begin to shrink. Our relationship would be so lopsided that there might cease to be, at least to me, anything subjective about you. As I learn what reactions you will have to stimuli, why you do what you do, you will become like any other object to be manipulated. You would be, as we say, dehumanized.

If someone knows everything about you, and can manipulate you to their whim, you cease to be a human being. If that’s not scary, I don’t know what is.

Now, we’re still far from this scenario (last time I bought a pair of sunglasses on line, I encountered pointless ads for sunglasses on most sites for months after) . In fact, it’s not clear to me that we will ever get to the point where we can accurately make predictions on the actions of single human beings. [BTW another great article on the topic, from a more practical standpoint can be found here]. But I hope that I’ve made a case that privacy is something that is so important that we should all be discussing it.


Later this month, we’re lucky to have Jari Saramäki visiting and speaking at the lab. Jari is an expert on temporal networks (I highly recommend the excellent review paper on temporal networks that Jari co-authored with past and future guest of the lab, Petter Holme).

Jari is an associate professor at Aalto University and a highly cited author of many high impact papers on complex networks, for example:

  • Jari Saramäki, E. A. Leicht, Eduardo López, Sam G. B. Roberts, Felix Reed-Tsochas, and Robin I. M. Dunbar. Persistence of social signatures in human communication. PNAS 111 (3) 942-947 (2014).
  • Lauri Kovanen, Kimmo Kaski, János Kertész, and Jari Saramäki. Temporal motifs reveal homophily, gender-specific patterns, and group talk in call sequences. PNAS 110 (45) 18070-18075 (2013).
  • J.-P. Onnela, J. Saramäki, J. Hyvönen, G. Szabó, D. Lazer, K. Kaski, J. Kertész, and A.-L. Barabási. Structure and tie strengths in mobile communication networks. PNAS 104 (18) 7332-7336 (2007).

Below are the details of his talk.

From minutes to months: call network dynamics at multiple timescales

  • Date: 27th of January
  • Time: 14:00
  • Location: Auditorium 040 in DTU Building 324.

Abstract: Big Data on human interactions and communication have revolutionized the ways how human behaviour can be approached from a quantitative point of view. Mobile telephone Call Detail Records (CDR’s) have proven especially fruitful for understanding one-to-one communication patterns and the dynamics of inferred social networks. I will discuss what happens and when in call networks constructed from CDR’s with time stamps; this talk can be considered a mini-review of what we know about temporal networks of mobile telephone calls. I will begin with short timescales and fast dynamics (such as burstiness of sequences of calls between individuals) and “zoom out”, from temporal motifs formed of correlated calls between multiple individuals to long-term dynamics of personal networks of individuals.

Privacy Part I: Why everyone is complaining, but no one is taking action.

[This is part II of a series, you can find the overview here]

We all have a sense that privacy is important. A sense that our ability to freely express “who we are” is slowly eroded by large corporations and governments collecting data on our actions for purposes not clear to us (and maybe not to them either). But on the other hand, no one is doing anything about this. Why is that?

I think that there are two central reasons for this.

The first reason is that humans are not very good at handling situations where cause and effect is separated by a lots of time and space. (I was made aware of this point by an excellent column in the Guardian by the author Cory Doctorow, who I will be stealing from in the following). There are lots of examples of this: No one would smoke if you developed cancer immediately upon the first drag of a cigarette. The possibility of cancer is so far away in time that it feels like the consequences happen to another person. You would be less likely to  binge-eat if the food immediately was converted into belly flab.

Something similar is going on with privacy. You don’t immediately notice any problems when you hand over all of your email correspondence to Google or outsource your social network to Facebook, or signing up for free Airport Wifi. And it’s even worse because we don’t even know what the consequences of sharing those data might be. Figuring out what we can learn about individuals is an emerging field. And while we know that you can estimate e.g. your political views based on your Facebook feed, we’re still working out what it really is that you’re revealing about yourself, when you’re sharing data … and how those pieces of information can be used to manipulate you.

In fact, the entities that know most about what your personal data can be used for (e.g. Google, Facebook, Apple, Amazon), have very little incentive to share this information with the general public. In part because opening up can damage their public image (e.g. the Facebook mood experiment), and in part because sharing insights might run counter to shareholder interests (e.g. making tons of $$$ manipulating people) [1]. This is why the kind of research that we do here at DTU is so important – providing a public and open counterpoint to large corporation with private research divisions.

The second (and even more important) reason is that it is not at all clear what kind of action we should take. Privacy is such a complex issue that even if you want to take action, there is no obvious path to follow. To make such a path a little bit clearer is, my goal with the posts in this series. I’ll try to find a little bit of solid ground so that maybe we’ll have something to mobilize around once we feel like it’s time to take action.


[1] Thanks to Piotr Sapiezynski for making this point.