VIX futures market

The VIX is the ticker for the Chicago Board Options Exchange Market Volatility Index, which measures the level of 1-month implied (i.e. anticipated by the market) volatility in the S&P 500. It is constructed from a wide range of S&P 500 listed call and put options.

The exact definition is in this paper pages 3-9.

Below is a historical graph of the VIX since December 2006.

The Power of Visualisation

Let us first quote Wikepedia verbatim:

'The adage "A picture is worth a thousand words" refers to the notion that a complex idea can be conveyed with just a single still image. It also aptly characterizes one of the main goals of visualization, namely making it possible to absorb large amounts of data quickly.'

Now let us make some slight amendments:

• append 'or dynamic interactive images' to the first sentence.
• append 'or grasp complex notions almost instantly' to the last sentence.

You then have the updated definition of the power of visualization. There is nothing conceptually new here, of course.

Charles Minard made his famous flow chart of Napoleon's disastrous Russian campaign in 1869 (see below). In a sweeping look, you can see the number of men as the armies advance, the main cities on their path, the rivers they go through, and the dates and the deadly temperature on they way back, all at once.

It is proof of how the potential of visualisation was already understood as far back as in the 19th century. Incidentally, this map is a also a memorable representation of the abyss leadership's hubris can lead to.

Photo Cube

In my exploration of the various javascript libraries, I ran into three.js. It enables the user to do 3D in the browser without going into the complex underlying math.

I found it well conceived. Its structure is relatively easy to grasp and the syntax is usually self explanatory. As a result, somebody with very little experience in javascript/programming, like me, can create reasonably good looking effects in a few hours. You just have to define a scene, a camera, some objects (cubes, spheres, etc), and a renderer (WebGL, Canvas, SVG - the best option, if available is WebGL, as computations are performed by the GPU). By default the camera faces the (xy) plane, the x axis x being horizontal pointing right and y vertical pointing up. The z axis is orthogonal to the screen pointing to the viewer. Axes and a 'test' small sphere are convenient to get orientated.

For some time, I had being looking to do a photo cube, so that the experience of going through the pictures is less boring.

With this in mind, I dived into three.js, googled around and found some very useful pages:

• Mr Doob's site.
• Johanes Raida's enlightening series of tutorials.
• The large collection of examples in AlteredQualia.

Below is the result.
The 'drag to spin the cube' works on an iPad too.




The code is available in this github repo.
You can easily tweak the point of view, distance of the camera, angle of view, amongst others.
And the pictures, of course ! I just put what I like as an example 

Map of France

When I was a kid, every summer, we used to drive across the country to the summer family house where we would stay for a month, or two. The school summer holidays were and are still very long.

At the moment the debate about school weekly timetable is raging in France. The government wants to reduce the amount of class time during the school day and add an additional half-day on Wednesday. France has the shortest school year and the longest school days of Europe. Such daily long hours on one hand, and long idle summer months on the other, make a very peculiar weekly and yearly rhythm. Needless to say this situation is not favorable to learning, particularly among less gifted children.

As most social equilibria in France, it is the result of a balance of power between several entrenched corporations, teachers, unions, formerly the Church (which negotiated a day dedicated to religious instruction after public school took over from it in the late 19th century), but obviously not children..

While the status quo is clearly bad for eduction, while the performance of French pupils/students is said to deteriorate relative to those of other industrialized countries (I have cannot quote the source but by all accounts of the teachers that I know the level of the average student has fallen dramatically), while the country is less and less industrialized, while speaking fluent English remains unusual, while the impact of school in the creation of citizens is eroding and its prestige has almost disappeared, it should be urgent and a no brainer to try and act quickly and boldly.

Germany for example is an interesting model. Pupils/students spend significantly less time at school, but their weekly time table is more evenly spread, they have more time to extra scholar activities (sports, music, etc), their summer holidays are much shorter, and their are better on the PISA scale. Such a ranking is always subject to interpretation, so one should not over interprete it. But then isn't Germany's economy and industry doing well ? Isn't our neighbor comfortably more wealthy ? It couldn't if its education system was that bad. So we could get some inspiration from them.

But surprisingly the individual interests of the teachers and some parents who want a convenient timetable for themselves prevails. The strikes are massive, the teachers vehemently oppose the reform, and the government shall step back, as always, whether right wing or left wing. There seems to be little sense of the public good, even among civil servants, and for sure hardly any notion of long term, in the corporations organising these demonstrations. I have not studied the proposal in detail, but I am aghast at the systematic blocking behavior of these corporations, and the power they derive from their control of the streets, outside any democratic process.

From Vedutismo to Mandelbrot Fractals

Last month, I went to see the Vedutismo (In Italian veduta means view) exhibition in Musée André-Jacquemard, with a few friends.

The Vedutismo is the 18th century school of painters who specialised  in scenes of daily life in Italian cities and mainly Venice.

The first maestro was Canaletto, who immortalized the various faces of the Venice of his time. He had perfectly mastered the technique of perspective, and used a camera obscura to create the layout his canvases. His paintings are impressive for their architectural and geometrical accuracy and great attention to brilliant details. They are often bathed in sunlight.

The second great painter of the exhibition, Guardi, was influenced by Canaletto in his early years, but gradually evolved to a less linear, sort of impressionist style. The scenes tend to be less glamorous, the waters are murkier, and the skies cloudy. But despite this looser painting style, the geometry and perspective are faultless.

Enough words, here are the canvases, two from each.
Can you recognize who painted what without reading the captions ?

Piazza San Marco - Canaletto