Mapping Our Friendships Over Time and Space: The Future of Social Network Analysis

What new things could we discover if social network analysis took time and space into account, in addition to the raw connections between people? In most cases, social network analysis today is limited to discovering friend connections, community leaders and outlines, influential people and personal friend recommendations - in a static or snap-shot kind of way. If new factors could be taken into consideration, specifically changes over time and space, then social network analysis could discover things like emergence or decay of leadership, changes in trust over time, migration and mobility within particular communities online. That's very valuable information that the social web has barely begun to tackle capturing.

That's the topic of discussion in a new paper by Shashi Shekhar and research assistant Dev Oliver, spatial data scientists at the University of Minnesota, titled Computational Modeling of Spatio-temporal Social Networks: A Time-Aggregated Graph Approach (PDF). The paper was highlighted on the blog GIS and Science today. We've excerpted and put in context key points below.

The Impact of Space and Time on Networking

Space and time are big factors in determining the diverse friend connections that different people form. Or, as Shekhar and Oliver put it, "Spatio-temporal constraints (e.g., geographic space, travel, schedules and diurnal [daily] cycles) play a major role in determining baseline homophily due to reasons like opportunity and minimization of cost and effort."

In other words, if we don't pay attention to the way space and time factor into our lives, if we just see who knows whom and who chatters about what, then we'll have a very blunt understanding of the world. Diurnal cycle in, and diurnal cycle out (!) businesses and software users seem likely to call for more clarity than that in the future.

Consider the diagram below, for example, from Shekhar and Oliver's paper. It might look a little intimidating, but if you follow it step by step from left to right, it's not. Today we might look at a group of four participants in some network and just see the final timeframe of connections (t10). You can see who knows who and who doesn't know who. But imagine if time were taken into consideration as it is here. You can see how this particular mini-network unfolded from the first connections, through the end-point. That's a much richer understanding of this group.

Look at poor little Node 3, for example, in the bottom of the square. It took them longer to go from Visitor to Friend than it took anyone else, in each of the relationships Node 3 formed. Node 2 at the top, on the other hand, looks friendly and effective at building strong relationships quickly.

Social network analysis services see these differences in the way people interact already and they see the way changes in spacial relations impact them, but it's a very nascent field.

"We see the spatio-temporal effect manifest in Twitalyzer data during conferences, tradeshows, and live events (e.g., SXSW)," says Eric Peterson, creator of professional Twitter analysis service Twitalyzer. 

"The results are pretty obvious in our data: individuals who exhibit an otherwise 'normal' level of Impact, Influence, and Engagement in our data go 'off the charts.'

"The simplest explanation is that there is a compressing effect on an individual's network when they are more spatially proximate (e.g., can grab a drink and interact face to face.) When this happens, especially when it happens over a short period of time, people's scores change, their networks expand (typically, although we have seen contraction), and their 'chatter' (in your words) becomes more focused."

As Yet Unanswered Time-based Questions of Value for Any Community

• How is trust or leadership changing over time?
• Who are the emerging leaders in a group?
• What are the recurring changes in a group?
• How long is the tenure of a leader in a group?
• How long does it take to elevate the level of trust such as a relationship changing from visitor to friend?

Now imagine that kind of temporal and spacial analysis being performed on much larger networks, over greater periods of time.

"This added dimension or set of data points is out there and generally widely available as 'exhaust data', so to harness it and factor it in with the rest of the social graph would be truly valuable," says Eileen Burbidge, a London angel investor at White Bear Yard and a former product manager at Skype, among other positions.

"From an investment (i.e. value creation) point of view, spatio-temporal data has the potential to add an element of value, context and relevance to otherwise 'flat' data points.

"Take LinkedIn for example. I use it to see who in my network knows (and might endorse) whom, but I'm often cross-referencing/checking a person's contacts by their work history to discern if a specific contact was established at one spatio-temporal point vs another (ie relevancy)... The ability to build this into social network analysis would be extremely valuable as space and time offer tremendous context and relevance to social connections and relationships. "

The Hard Parts

That could very well be the kind of sophisticated social network analysis that service providers aspire to in the future and that their customers seek. Identifying some basic opportunities doesn't mean it will be easy to get there, however.

Shekhar and Oliver say this points to the need for "a central role for computation and computational models, not only to scale up to the large and growing data volumes, but also to address new spatiotemporal social questions related to change, trends, duration, mobility, and travel.

"The need for computational efficiency conflicts with the requirement for expressive power of the model and balancing these two conflicting goals is challenging."

If each historical moment of our relative connective history becomes no longer exhaust data, but points on a chart, that sure is going to be a challenge in the computational efficiency department! Presumably, it will just be timestamped changes of state that will be preserved.

Scaling that analysis is one challenge, finding new ways to recognize, tell and leverage the stories unearthed by analysis of that data is a whole other challenge.

Shekhar and Oliver cast themselves into the abyss of that data-centric future with their conclusion: "We welcome collaboration towards identifying datasets and use-cases to evaluate the potential of TAG [the time aggregated graph model] to address spatio-temporal questions about social networks."

Good luck guys, may you help open up this whole new frontier to us all. You've certainly articulated something that a whole lot of people are going to be very interested in in the future.

Right: A slice of Veronica Belmont's closest Twitter buds, per Mailana, a system without reference to time. From The Inner Circles of 10 Geek Heroes.

Title photo: Blinded by the Light, by Flickr user Jule_Berlin

Why You Learn More Effectively by Writing Than Typing

The act of writing helps you clarify your thoughts, remember things better, and reach your goals more surely. Here's a look at the science and psychology behind writing, and why the pen may be mightier than the keyboard.

Photo by sun dazed.

Many productivity experts and writers have long espoused the power of writing things down (in fact, paper is our many of our favorite to-do list manager and we're a little fanatical aboutour favorite pens).

Why Writing Works

Patrick E. McLean's defense of writing longhand is a poetic dissertation on the subject; words can rush out in their raw, feral state when the pen is your tool. Technology, meanwhile, can be too distracting and distancing.

Maybe you're on the other side of the fence, though, and think all this just a lot of pure romanticism: People may feel more comfortable and productive with pen and paper because that's what they've used most of their lives (and what we as a species have used for centuries), but some like typing more and can do it more quickly. Certainly, more of us are becoming fast typists by necessity and the art of handwriting is deteriorating.

A couple of studies, though, substantiate why the physical act of writing really does boost learning and goal achievement. Hoping to provide actual scientific proof on the efficacy of writing down and sharing goals (to make up for an often-quoted mythical Harvard/Yale study of goals), a psych professor at Dominican University of California found that people who wrote down their goals, shared them with others, and maintained accountability for their goals were 33% more likely to achieve them, versus those who just formulated goals. (One can argue that in this instance, typing would be equally effective; see "Why Writing Works Better Than Typing" below for why writing still may be better.) Another study found positive effects of writing on learning foreign words, and a survey of note-taking studies found several examples where taking notes helped students with recall and academic performance.

The research results may seem common sense or obvious to many of us. If you're interested in the biology behind writing's effect on our achievements, though, here's a little background: Writing stimulates a bunch of cells at the base of the brain called the reticular activating system (RAS). The RAS acts as a filter for everything your brain needs to process, giving more importance to the stuff that you're actively focusing on at the moment—something that the physical act of writing brings to the forefront. In Write It Down, Make It Happen, author Henriette Anne Klauser says that "Writing triggers the RAS, which in turn sends a signal to the cerebral cortex: ‘Wake up! Pay attention! Don't miss this detail!' Once you write down a goal, your brain will be working overtime to see you get it, and will alert you to the signs and signals that […] were there all along."

Why Writing Works Better Than Typing

There may also be a scientific basis for the pen's superiority over the keyboard when it comes to writing development and cognitive functions. Dr. Virginia Berniger, who studies reading and writing systems and their relationship to learning processes, found that children's writing ability was consistently better (they wrote more, faster, and more complete sentences) when they used a pen rather than a keyboard; these are, of course, subjects without a penchant for using either tool. We also previously covered the WSJ article that connected handwriting and cognitive abilities; in one of the studies cited, adults learned new symbols and graphic shapes better when they reproduced them with pen-and-paper instead of typing them.

The difference, Berniger notes, may lie in the fact that with writing, you use your hand to form the letters (and connect them), thereby more actively engaging the brain in the process. Typing, on the other hand, involves just selecting letters by pressing identical-looking keys.

Of course, whether the pen or the keyboard is better for you depends on your personal experience and comfort with these tools. As a compromise, perhaps we should all get stylus-friendly tablet PCs or digital pens.

The author of this post can be contacted at tips@lifehacker.com