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January 30, 2011

Networks of the Brain


If you have not discovered this book yet, take a look.
Highly recommended. Fascinating.

sporns networks.png

Summary: Over the last decade, the study of complex networks has expanded across diverse scientific fields. Increasingly, science is concerned with the structure, behavior, and evolution of complex systems ranging from cells to ecosystems. Modern network approaches are beginning to reveal fundamental principles of brain architecture and function, and in this book, Olaf Sporns describes how the integrative nature of brain function can be illuminated from a complex network perspective. Highlighting the many emerging points of contact between neuroscience and network science, the book serves to introduce network theory to neuroscientists and neuroscience to those working on theoretical network models. (...)

March 23, 2009

The social psychology of Facebook, etc.

What is the motivation behind Facebook and other forms of online self-presentation, such as, say, blogging? I posed this question (with respect to Facebook) to my undergraduates. Their answers included a desire for social contact and curiosity about other people (for which, perhaps, self-disclosure is the medium of exchange). Here are some other possibilities:

1. According to Cooley, we see ourselves through the eyes of others, or at least we try hard to. But what others? Whomever we come into contact with, I suppose, for those are the people whose reactions we can gauge. But then online self-presentation poses a challenge, for this is presenting ourselves to people we might not otherwise encounter, and whom we might not ever encounter in person. I conjecture--and perhaps Cooley anticipated this--that we see ourselves through the eyes of whomever we've received responses from in the recent past. Then once a blogger has, perhaps under pressure from a former colleague, presented himself to the blogosphere once and received some responses, he sees himself through the (imagined) eyes of those same people (or at least some typification of that sort of person), and feels answerable to them.

2. Once one has a taste of externalizing one's thoughts and imagining that others care to ponder them, thinking that is not externalized seems kind of pointless, perhaps like singing in the shower after performing in front of a large audience. I've had this experience after reviewing books for journals, of feeling deflated upon then reading a book for no one's benefit but my own. (It passes, unless one feeds the habit by writing Amazon reviews.)

3. Consistent with (2), one acquires the cognitive habit of thinking and experiencing on behalf of an audience, and perhaps of formulating a blog entry as the experience unfolds, so that half the work is done by the time the experience is complete. Whether this diminishes the intensity of the original experience, I won't conjecture. Obviously Twitter takes this to a new extreme.

4. When my students talk about maintaining social contact, I assume they mean contact with high school and college friends, and that a precondition for friendship is, at least in some circles, continuous self-accounting and monitoring of the self-accounts of others. This should probably be distinguished from blogging (or Facebooking) to combat genuine isolation, of the sort that my students are at little risk of but that probably besets folks stranded in the suburbs and beyond. The problem with this formulation is that it portrays online interaction as a last act of desperation, akin to talking to a Wilson soccer ball, whereas it seems that a genuine, if virtual, community readily pops into existence for anyone looking for one. And then who's to say that it's less "real" than a clutch of friends chatting at the coffee shop? As I tell my students: no moral evaluations. No, not even in the footnotes.

February 3, 2009

Christakis and Fowler in SCIENCE, 23 Jan 2009 Issue

The golden boys of networks in public health are featured in this week's issue of SCIENCE.christakis fowler photo.png

From the headline of the article:

Friendship as a Health Factor
In a string of hot articles, two social scientists report that obesity, smoking, and other facets of health "spread" in networks. As the two friends expand their theory, doubters sharpen their questions.

The story is way cool. Their research, and the ground that they are breaking, are way cooler.

June 18, 2007

Psychological Traits from Social Network Characterstics

Peter Gloor and Daniel Oster, some of my collaborators from MIT and the University of Cologne, respectively, recently showed that they were able to predict neuroticism and extroversion on a standard psychological test (NEO-FFI) using data from our Sociometric badges in an experiment at a German bank's marketing division (see this earlier post for a description).

They examined the disparities in the infra-red (IR) hits between individuals, using this to determine how "balanced" their communication was. One badge can receive an unreciprocated IR hit from another badge because IR requires a direct line of sight to transmit data. Therefore, if one individual is not directly facing another person, they may recieve IR transmissions. Their conversation partner, however, will not receive anything.

The authors then processed this sensor information into a higher level "contribution index". The contribution index was previously defined by Gloor for e-mail data in online standards communities, and it is essentially: (number of messages sent – number of messages received)/(number of messages sent + received). Here it is defined as numbers of infrared readings picked up by an actor. The higher the value, the more signals an actor picks up. A contribution index of 1 means that an actor looks at other people and is never looked at, while a contribution index of –1 describes an actor who is only looked at while never looking another actor squarely into the face.

The authors found a correlation of -0.74 with neuroticism and a 0.52 correlation with extroversion, which intuitively makes a lot of sense. This work shows the promise of using precise sensor data to map not only social relations on a large scale, but using it to quantify individual personality types as well.

This work is currently under review for submission.

February 13, 2007

How does the way we process information relate to how we search for it?

Some days ago I attended a talk on human information processing by Thomas Mussweiler from the University of Cologne who spoke at the Columbia Business School. Mussweiler and colleagues conducted an impressive number of experiments on the mechanisms and influences of individual information processing. A simple example would be to ask you to determine your best athletic performance. You have two basic options: 1) You think of every single athletic moment in your life, i.e. you engage in absolute information processing, or 2) you compare what you recollect as some of your best performances to a given standard, e.g. a famous athlete’s performance (or a famous couch potato’s performance). Not surprisingly it turns out that comparison allows to process information in a more efficient manner.

Mussweiler went on to talk about various factors that influence the comparisons we make, most importantly the standards we employ for comparing information. His experiments used a technique called “priming” to activate certain standards – for example, subjects were asked to judge a trait in a person. The result shows that priming a trait concept (such as aggressiveness) will induce the subject to judge the target person according to that trait. In other words, once activated, standards are spontaneously compared to the target person.

While I was listening to the talk, I kept asking myself how the way we process information relates to how we search for it. Some possible bridges might be that the search itself is the result of some form of information comparison (my search is triggered by a comparison of the information I have to a “standard”, which is the knowledge I believe I need to possess), and/or that we subconsciously use standards to determine the source to turn to when searching for information. I don’t know if there’s literature out there that links cognitive psychology to advice networks, but it's definitely something useful to look into.