Using Networks

Salmon need artificial pigments

I love this so much. Bring on the language games.

A recent TV advertisement in the UK has stirred up the salmon farming industry. The advertisement shows a man in a lab describing how farmed salmon is coloured with the chemical Astaxanthin. The speaker then holds up on of the now famous "Salmon Colour Charts"

- (via a message found at EdwardTufte.com - in a discussion about Salmon colour charts)

And now, some of the text from a press release from the salmon industry. Look out for the language games -- they're not immediately obvious. No, really.

“Captain Birds Eye charts the wrong course in advert about farmed salmon” says Scottish Salmon Producers’ Organisation

“The Scottish salmon farming industry is very disappointed that Birds Eye has chosen to take this rather melodramatic and cynical approach to its advertising when the fact is that salmon, wild and farmed, are pink because they consume carotenoid pigments. In the wild, salmon take up this pigment from such food items as shrimp and other organisms. Our farmers simply provide the same elements in their feed and the same natural process in both wild and farmed fish means that the pigment is absorbed into the body.

[...]

Salmon cannot synthesize carotenoid pigments and so must find them in their diet, to assist the reproductive process and protect the eggs. Colour charts are used to ensure that the salmon are fed sufficient quantities of carotenoid pigments to meet their and the consumers’ needs.

- via the SSPO, but italics added.

I wonder my supermarket is using the same logic for its smoked haddock - do I need it to be pigmented with that acid yellow colour?

links for 2009-07-16

• ' Generalized blockmodeling ' (pdf)
  (tags: blockmodelling generalized)
• wePapers - Creating the world's biggest study group
  (tags: online paper community research learning document)
• The Human Terrain System: A CORDS for the 21st Century | The U.S. Army Professional Writing Collection
  Short artivcel summarising the history, purpose and nature of the US Human Terrain System
  (tags: military social anthropology culture)
• Michelle Paver's favourite books on archaeology and anthropology | Books | guardian.co.uk
  A good list, this, with some favourites, some new.
  (tags: archaeology anthropology books)

Email policy

I spend many working days away from the office, and many office hours in meetings. Like most people in large organizations, I receive hundreds of actionable emails a week. I can only access these while at work. And my working days are usually over-committed.

Consequently, I just cannot give every email equal attention. Email is, of course, a broken tool - and a working culture that expects a rapid, pavlovian response from the recipient is not one in which anyone can concentrate long enough to do high-quality work.

To manage this as best I can, I use a kind of 'triage' system, based on the book 'Getting Things Done': each email is automatically 'read' and categorized, and I re-prioritize and work through these lists and my voicemail a couple of times a day. Incidentally, this means that receiving a read receipt for an email does not mean that I've read it!

So, if I haven't responded to your email, I'm either not in, or I'm focussing on delivering work required urgently by another customer. Sorry, but there it is.
And if I've sent you a very curt email - say, four sentences long - I'm doing my bit to save you time (see http://four.sentenc.es/). Feel free to do the same to me.

-Mark Round

Categories and equivalences (redux)

To revisit a familiar argument: I find categorization to be a useful process, when engaged in exploratory analysis, if the categories themselves are up for grabs (and not just the assignments to those categories). For an example, the process of partitioning a network into sets of structurally-equivalent nodes -- those that share connections with the same others -- is an essential part of most network analyses. But the patterns of structural-equivalent sets are not always easy to interpret, as there isn't always a category label at hand with which I can make sense of the patterns found by the algorithm.

'Regular' equivalence causes me similar problems. Two actors are regularly equivalent if they have similar patterns of ties to equivalent others. A slightly abstruse definition, but an intuitive concept, given a proper exemple. Take a network describing communication behaviour within at least a medium-sized organization: you would expect to see certain patterns recurring within certain subsets - 'team leaders', 'technical managers', 'salesmen', etc. Some will match formal, appointed roles, but others will be categorising emergent niches in the structure. Many of these latter categorizations will not have clear given names. They may differ from equivalence-sets in networks from similar organizations, reflecting instead the peculiarities of the organization under study.  Finding these and naming them -- as a categorization process -- I find to be hugely useful in getting under the skin of an organization.

In the past I've likened the process to early biology. This may be slightly grandiose (and certainly not original - see Morgan, 2006), but it's almost as if each new organization is a new ecosystem, full of new species. We can see some convergent evolution going on, but we shouldn't be blinded by expecting it.

On categories (Marsay)

I had a comment on the post “Friends, acquaintances, and Facebook” from a colleague, Dave Marsay, that I thought worth its own post.

Mark: As a fan of Lewis Carroll, I not only wonder if the categories may not have changed and if (whatever) constrains the richness of human relationships, but if the notion of category as a means of viewing (whatever) has outlived its usefulness and constrains human relationships - maybe even in a 'bad' way. At the same time, tools like SNA are clearly essential. The problem, then (as with much else) is to develop theories of use that can provide the context for routine use. One argument against categories, adapted to this case, is a follows. Categories make sense in the context of stable systems, e.g. stable societies. But social networking is transforming social affairs. In math-speak, categories are the invariants of 'the system' - but 'the system' is changing. The use of the tools subverts their assumptions. Another (controversial) argument is that it would be inhuman to deal with our fellow humans as instances of categories, rather than as individuals. Arguably, then, any theory based on categories would be a part of the anti-social sciences. Of course, in many cultures reliance on categorisation is endemic, and until a few weeks ago it was commonly argued that the economic and military strength of such cultures proved the merit of this approach. If this consensus were to change it would radically affect 'who we would ask for a favour', and SNA, for example, would not be of much help in understanding what was going on. Social Networking tools, on the other hand, could be very useful, and could help drive any change. You will appreciate that I have difficulty in saying anything about the universality of human experience, beyond yes and no - and don't know. I'll maybe ponder. Regards.

I'll leave it to stand for a while, and comment in a post sometime in the next few days.

Friends, acquaintances, and Facebook

I know that it's good science to test common sense beliefs. It's never sexy, and it's tougher to get grants to do it, but - all the more reason, eh? And I've never previously been that interested in the study of ego-networks, the aggregation of results about the social patterns around unconnected individuals. It's always seemed too like the 'science of the central tendency' that I've been trying to avoid all my life.

As a psychologist discovering SNA, I've always been fascinated by emergence - of coherent vision from noisy neuronal firing, of thought from neuronal activity, of a single consciousness from a modular mind. So, in SNA, it was the emergence of intermediate and global properties (cliques, boundaries, bridges, robustness, adaptability, centralization) that was fascinating.

But surprise should always be respected. I've been reading Degenne & Forsé (1999), and came across some figures on the nature of individual social life that really stretched my credulity. If you like, read the question below and guess for yourself (answers below the line). I'm curous - is it me, or are these really surprising results?

If you were asked what, for a Western European adult, was the average number of

• (i) friends,
  
• (ii) immediate contacts (people you might approach to ask a favour, for example), and
  
• (iii) acquaintainces,
  

what would you estimate these numbers to be?

-----------------------------------------------------

From Degenne & Forsé:

François Héran (1988b) summarizes that: ' The average adult sees seven kin per month, in-laws included. He has three or four friends, does one favour per year for one or two neighbouring households and belongs to one civic organisation. That sums up the social life of the average individual aged 18+ years living at home, i.e. in any non-institutional environment.'
...
A personal network is a series of concentric circles centred on the individual. Acquaintances form the largest, a virtual network that includes everyone the respondent has ever met. The average for this outermost circle is about 5,000 people. The circle of immediate contacts is far smaller. The average respondent has only 100 to 200 people he can contact to link himself up to a target stranger. She has regular talks with fewer than 20 people per week, subject to variation with age, sex, education and other sociodemographic criteria. Again, real confidants average only three.

As many as 5,000 acquaintances? And only three friends? And these are averages. But what's really intruiging me is how this relates to the niches to be filled by artificial social networks: Facebook, LinkedIn et al. I'm party to a few of these - purely for research, of course - and I've often felt that each can feel a little ... strained, in use. And I now think this is due to the way that they take these naturally-multiple levels of 'friendship' (or tie strength, for want of a sharper technical concept) and flatten them into a single homogenous ring.

There's a business idea, here. Yet another social network start-up, anyone?

links for 2008-07-15

• Hypothesis testing - What’s Wrong with ACH? « Rationale Thoughts
  Interesting critique of the Analysis of Competing Hypotheses method, by Tim van Gelder (of the Rationale tool, and some famous anti-representationalist arguments). Worth a good scan.
  (tags: argumentation analysis competition hypothesis)

links for 2008-02-18

• Visualizing Social Networks (Freeman, 2000)
  This paper documents the use of pictorial images in social network analysis. It shows that such images are critical both in helping investigators to understand network data and to communicate that understanding to others.
  (tags: visualisation social network analysis)
• Netvis Module - Dynamic Visualization of Social Networks (online)
  (tags: applet graph network social analysis online software visualisation)

links for 2008-01-21

• Pajek Wiki
  Vlado has added a wiki to the Pajek site. If only all SNA tool developers did this.
  (tags: wiki Pajek tips training social network analysis)
• Pajek Manual v1.22 (Jan 08)
  The latest (Jan 08) version of the Pajek manual is to be found here.
  (tags: social network analysis Pajek tips training)

links for 2008-01-08

• visualcomplexity.com | Method View
  Great gallery of tagged network visualisation images, as you'd expect of this site.
  (tags: radial convergence network visualisation pictures elliptical tree arc)