Why Wikipedia’s “Editor Exodus” Doesn’t Matter: A Closer Look at the Data

30 11 2009

On November 23, the Wall Street Journal reported that “unprecedented” numbers of Wikipedians were leaving the site and suggested that Wikipedia was in grave danger.  The story was later picked up by CNet and other sources.

Wikimedia produced a rebuttal saying that everything was fine.  However, the media is portraying the battle as a “he said / she said” affair where it is not clear whether Wikipedia is in trouble or not.  We think this fails to credit Wikipedia as holding the stronger of the two positions.

In this article, we discuss why Wikipedia’s “editor exodus” doesn’t matter.  Simply put, the WSJ has (1) interpreted the data incorrectly, (2) ignored the fact that most content on Wikipedia is created by a small, core group of editors [a fact validated by researchers at U. Minnesota], (3) ignored social science research indicating that having fewer editors may increase article quality, and (4) ignored the exodus of spammers.

The exodus described is the leaving of 49,000 editors from the English language version during the first three months of 2009, where only 4,900 left in the same quarter a year earlier.  It is stated that editors are leaving faster than new editors are joining.  All the statements made in the WSJ article are supported only by data provided by Dr. Felipe Ortega of the Universidad Rey San Carlos in Madrid.  The data is in his thesis on Wikipedia (the relevant data starts on page 116).

Ortega’s Analysis

Dr. Ortega shows that more editors are leaving Wikipedia than joining it, as shown by the greater number of editor deaths than births in the following graph.  He defines a birth as the moment when someone edits Wikipedia for the first time.  He defines a death as the moment when someone makes their last edit to Wikipedia, which is not followed by any further edits.

The 49,000 “log-offs” reported by the WSJ are what Dr. Ortega would call in his thesis 49,000 deaths.

The following image is the birth/death graph for the English version of Wikipedia from page 123 of Dr. Ortega’s thesis.

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Building 3D Models on the Fly Using a Webcam

25 11 2009

A new technology developed by Qi Pan and other researchers at the University of Cambridge allows one to create 3D models on the fly by manipulating an object in front of a webcam. The reconstruction of the 3D model from the video can be viewed in real-time by the user as he moves and rotates the object. The program is called ProFORMA. Pan says the program will be publicly released soon.

The following video gives an excellent demonstration.

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Tag Images with Your Mind

25 11 2009

Assigning textual tags to an image is an important task because tags are needed for things like image search. When you search for an image of a “cat,” modern search engines can only identify an image as containing a cat if the tag “cat” is associated with it.

Having people tag images by hand is an onerous task. Shenoy and Tan of Microsoft Research developed a way to tag images automatically by reading people’s brain scans while they look at images. The people did not even have to specifically think about trying to tag the image; they merely had to passively observe it.

Reading Minds

The technique requires using an electroencephalograph (EEG), a cap with electrodes placed on the scalp in regular locations that can each measure brain activity in their local area.

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Unflattening Touch Screen Buttons

24 11 2009

Ever wish the flat touch screen buttons on your phone felt more like physical buttons?

Chris Harrison and Prof. Scott Hudson at Carnegie Mellon have developed a simple technology that turns touch screen buttons into physical buttons by using pneumatics.

The technology consists of a flexible surface area with a hard backing that acts as a mask for the button shapes.  An air chamber behind the backing can be pressurized or depressurized using pneumatic technology, in this case fan-based pumps.

When positive pressure is applied, the buttons pop out.  When the pressure is neutral, the screen is flat.  When negative pressure is applied, the buttons pop inwards.

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Apple vs. Microsoft: Multi-touch Mouse Comparison

23 11 2009

Both Apple and Microsoft have introduced mice with “multi-touch” sensing.  This is arguably the first substantial improvement to the mouse since it was invented in 1968 by Doug Englebart.  Apple’s product, the Magic Mouse, is commercially available for $69.  Microsoft has 5 prototype mice that are still in the R & D stage.

Regular mice only allow movement via the palm and the clicking of a left, right, and middle mouse button.

Why not detect inputs from all 5 fingers all over and around the surface of the mouse?  Multi-touch sensing technology for touch screens has allowed detection of multiple simultaneous presses all over a display screen.  A multi-touch mouse simply applies multi-touch technology on a mouse.

This article will compare the Apple and Microsoft offerings.

Apple: Magic Mouse

The Magic Mouse is a straightforward application of multi-touch to mousing and is a tame improvement compared with Microsoft’s more radical designs.  The Magic Mouse is based on a regular mouse body but covers the top with capacitive sensors.  These sensors are the same that would be used in standard touch screens, like on the iPhone.

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