Category Archives: Web

The mathematics of opinion formation

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Here’s something to drive innumerate spin-doctors wild: a mathematical theory of opinion formation by Fang Wu and Bernardo Huberman of HP Labs. Abstract reads:

We present a dynamical theory of opinion formation that takes explicitly into account the structure of the social network in which individuals are embedded. The theory predicts the evolution of a set of opinions through the social network and establishes the existence of a martingale property, i.e. that the expected weighted fraction of the population that holds a given opinion is constant in time. Most importantly, this weighted fraction is not either zero or one, but corresponds to a non-trivial distribution of opinions in thelong time limit. This coexistence of opinions within a social network is in agreement with the often observed locality effect, in which an opinion or a fad is localized to given groups without infecting the whole society. We verified these predictions, as well as those concerning the fragility of opinions and the importance of highly connected individuals in opinion formation, by performing computer experiments on a number of social networks.

So now you know. The paper has lots of nice equations of the kind that make some people’s eyeballs revolve. But, at heart, it reaches reassuringly obvious conclusions. For example,

Our theory further predicts that a relatively small number of individuals with high social ranks can have a larger effect on opinion formation than individuals with low rank. By high rank we mean people with a large number of social connections. This explains naturally a fragility phenomenon frequently noted within societies, whereby an opinion that seems to be held by a rather large group of people can become nearly extinct in a very short time, a mechanism that is at the heart of fads.

These predictions, which apply to general classes of social networks, including power-law and exponential networks, were verified by computer experiments and extended to the case when some individuals hold fixed opinions throughout the dynamical process. Furthermore, we dealt with the case of information asymmetries, which are characterized by the fact that some individuals are often influenced by other people’s opinions while being unable to reciprocate and change their counterpart’s views.

Server power

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A new study by the Lawrence Berkeley National Laboratory (pdf available here) finds that:

Aggregate electricity use for servers doubled over the period 2000 to 2005 both in the U.S. and worldwide Almost all of this growth was the result of growth in the number of the least expensive servers, with only a small part of that growth being attributable to growth in the power use per unit.

Total power used by servers represented about 0.6% of total U.S. electricity consumption in 2005. When cooling and auxiliary infrastructure are included, that number grows to 1.2%, an amount comparable to that for color televisions. The total power demand in 2005 (including associated infrastructure) is equivalent (in capacity terms) to about five 1000 MW power plants for the U.S. and 14 such plants for the world. The total electricity bill for operating those servers and associated infrastructure in 2005 was about $2.7 B and $7.2 B for the U.S. and the world, respectively.

Nicholas Carr comments:

The estimate that servers account for 1.2 percent of overall power consumption in the U.S. is, as the San Francisco Chronicle reports, considerably lower than some previous estimates, which put data center power consumption as high as 13 percent of total U.S. consumption. It should be noted that the study, underwritten by AMD, looks only at power consumption attributable to servers, which represents about 60% to 80% of total data center power consumption. Electricity consumed by storage and networking gear is excluded. The study also excludes custom-built servers, such as the ones used by Google. The number of servers Google runs is unknown but is estimated to be in the hundreds of thousands.

It all goes to explain why Sergey Brin & Co are getting so exercised about power consumption.

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Escaping from Adobe’s clutches

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Here’s something useful:

PDFescape is a new way to open PDF files. It allows you to open your PDF files right here on the web without downloading or installing any software.

With PDFescape, you can fill in PDF forms, add text and graphics, add links, and even add new form fields to a PDF file. Best of all, it’s Free!

Have just one PDF form to fill out, but don’t want to buy $299 Adobe Acrobat? PDFescape is for you!

Have a PDF form you want customers to fill out and email back to you? PDFescape is for you!

Another useful web service. Thanks to Tony Hirst for the link. Of course, users of Mac OS X don’t really need it, because the operating system does pdf out of the box. But we’re only — what is it? — 5% of the personal computer world!

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Wikipedia: “an addressable knowledge base”

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Thoughtful post by Lorcan Dempsey…

I was looking at an announcement on the University of Edinburgh’s site about The British Academy Warton Lecture on Poetry, to be given this year on Yeats by his biographer Roy Foster. A distinguished event! I was interested looking to the bottom of the page to see links to the Wikipedia pages for both Yeats and Warton.

This seemed to me to show Wikipedia’s growing role as an addressable knowledge base. It makes further information about a topic available at the end of a URL. It relieves people of having to create their own context and background. As in this case, context, or condensed background, about Warton and Yeats is available for linking, relieving the developers of having to provide it themselves.

Condensed background is a phrase used by Timothy Burke, history professor at Swarthmore, and author of the Burn the catalog piece of some years back. I was rereading Burn the catalog earlier and was interested to come across his blog discussion of Wikipedia.

“I’m using Wikipedia this semester where it seems appropriate: to provide quick, condensed background on a historical subject as preparation for a more general discussion. Next week, for example, the students are having a quick look at the Malthus entry as part of a broader discussion of critiques of progress in the Enlightenment.”

And he goes on to comment on the Middlebury decision which is discussed in my post of the other day.

“Big deal. The folks at Middlebury are perfectly correct to say that students shouldn’t be using Wikipedia as an evidentiary source in research papers. That’s got nothing to do with Wikipedia’s “unreliability”, or the fact that it’s on the web, or anything else of that sort. It’s because you don’t cite an encyclopedia article as a source when you’re writing an undergraduate paper in a history course at a selective liberal-arts college. Any encyclopedia is just a starting place, a locator, a navigational beacon. I’d be just as distressed at reading a long research paper in my course that used the Encylopedia Britannica extensively. As a starting place, Wikipedia has an advantage over Brittanica, though: it covers more topics, is easier to access and use, and frankly often has a fairly good set of suggestions about where to look next.”

He uses Wikitedium in the title of the post, and I thought how apt an expression this was to characterize the periodic library discussions about Wikipedia which pitch authority against editorial permissiveness.

Wikipedia is a collection. Some entries are excellent, some less so. One cannot summarily judge its value in the way that one might have done when deciding whether or not to buy or recommend a reference book. Judgements about ‘authority’ and utility have to be made at the article level, and who has the time and expertise to flag individual articles in this way? Rather than continuing a tedious Wikipedia good/Wikipedia bad conversation, we should recognize the attraction it has as an addressable knowledge base, understand the variety of uses to which it is put, and remind folks of the judgments they need to make depending on those uses.

Gmail and docs

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Here’s an interesting development. If you have a Gmail account and receive (or send yourself) a Word or RTF document as an attachment, Gmail will now offer you the option of opening it as a “Google document” — which immediately makes it shareable (enabling other people to work on it collaboratively). And it’s seamless. Very neat — and immediately useful for people like me.

Wikipedia, you are the strongest link

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That’s the headline some clever Observer sub-editor put on this morning’s column…

There are two kinds of people in the world – those who think Wikipedia is amazing, wonderful, or inspiring; and those who simply cannot understand how a reference work compiled by thousands of ‘amateurs’ (and capable of being edited by any Tom, Dick or Harry) should be taken seriously. Brisk, vigorous and enjoyable arguments rage between these two camps, and provide useful diversion on long winter evenings.

What’s more interesting is the way Wikipedia entries have risen in Google’s page-ranking system so that the results of many searches now include a Wikipedia page in the first few hits…

Who owns the company intranet?

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Interesting findings from Jakob Nielsen’s Alertbox…

Intranets tend to have one of three homes in the organization. Of the 2005-2007 winners:

* 35% were in Corporate Communications
* 27% were in Information Technology or Information Systems (IT/IS)
* 19% were in Human Resources (HR)

The remaining 19% of award-winning intranets were based in a variety of other departments, including Web Marketing and Public Affairs.

If you had to select a single organizational placement for all the world’s intranets, statistics imply that Corporate Communications is the best place. But in reality, we won’t make that recommendation, since most great intranets are based elsewhere. The only recommendation we can make is to consider the history and culture of your own company and consider Corporate Communications, IT, and HR as the three most likely candidates.

Posted in Web

shortText.com

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shortText is a neat, simple idea. Suppose you want to post something quickly to the Web with a URL that you can distribute. Go to shorttext.com, type in the box and link to an image or video (if desired) and hit the ‘Create URL’ button. Bingo!

There’s also a shortText plug-in for FireFox which enables you to do the same by highlighting some text and right-clicking on it.

The bubble reputation

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This morning’s Observer column — on the eBay ‘reputation’ system…

It has become the linchpin of the eBay phenomenon. But as the importance of having a good reputation has increased, so has the temptation to manipulate the system. Fraudsters have been fooling the rating system by conducting transactions with friends or even themselves, using alternate user names to give themselves high satisfaction ratings – and luring unsuspecting customers to buy from them.

It’s difficult to know how widespread this scam is, and eBay is fanatically tight-lipped about it. Policing the billions of transactions that take place every year in its online auctions is a Sisyphian task. And reputation-faking rings have been difficult to spot, especially since there are lots of close-knit groups on eBay (for example, porcelain collectors) who trade intensively – and innocently – with one another…

This email address will self-destruct in ten minutes…

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Here’s a neat idea for dealing with sites which won’t let you use them unless you provide a valid email address that they can then use to spam you. — 10 Minute Mail. Blurb reads:

Welcome to 10 Minute Mail. By clicking on the link below, you will be given a temporary e-mail address. Any e-mails sent to that address will show up automatically on the web page. You can read them, click on links, and even reply to them. The e-mail address will expire after 10 minutes. Why would you use this? Maybe you want to sign up for a site which requires that you provide an e-mail address to send a validation e-mail to. And maybe you don’t want to give up your real e-mail address and end up on a bunch of spam lists. This is nice and disposable. And it’s free.