html5 – the initial elements

Let’s start with a simple HTML page which will illustrate the HTML5 changes; I will use an example for the demand & supply curves, just displaying a table and a chart picture.

Every SGML document (from which the HTML format is extended) starts with a DOCTYPE declaration, which associates it with the appropriate Document Type Declaration (DTD).

An XHTML1.0 (the latest HTML standard before HTML5) page has a declaration like this:

<!--DOCTYPE html
          PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"

This is the HTML5 doctype:

<!--DOCTYPE html>

That’s it. Just 15 characters. Already a nice change.

Continue reading “html5 – the initial elements”


Demand & supply

The demand and supply analysis is one of the main tool available to see how a market (the grouping of buyers and sellers for a specific good or service) behaves.

The demand curve is the equation (and the related graph) depicting the relationship between the price of a certain good or service, and the amount of it that consumers are willing and able to purchase at that given price. Continue reading “Demand & supply”

[Link] The risks of committee thinking

Tim Harford writes about how to avoid the “groupthink risk”: the tendency of committees to congeal around a particular point of view, reassured by the fact that everybody agrees with everybody else, and nervous about expressing dissent (highlighted in 1972 by the psychologist Irving Janis in his famous analysis of the Bay of Pigs fiasco).

The risk of committee thinking is that – paradoxically – a group of people may end up considering fewer alternative points of view than a single person.

Irving Janis argued that someone should always play the role of devil’s advocate, and different people should play the role at different times (the Catholic church invented the idea in the late 16th century.)
Experiments showed that if there was a single dissenter in the room, the experimental subject was far more likely to resist social pressure and pick the correct pair of lines. This was true even if the dissenter himself was also wrong. What mattered was that he said something different.


The microeconomics is the discipline studying the individuals’ decisions in scarcity conditions.
Scarcity means not only few goods or money but also not enough time or own capacity or any kind of resources.
At the end, every choice implies some kind of scarcity: if you have unlimited resources, you never need to choose between alternatives.

Very often, this choice can be evaluated as: are the costs for it bigger or less than the benefits of it? And the challenge is to find all the costs and benefits associated to the choice.

For example: let’s say I’m sitting on the couch listening to my Hi-Fi set and the song currently playing is one of my favourite: should I get up and turn up the volume or stay sit? (assuming that I have no remote for my Hi-Fi).
The benefit is to enjoy more my favourite song. The cost is the nuisance of leaving the couch.
How to decide?
If someone offers me 1 Cent to get up, I would probably stay where I am but if the offer is 1000 € I would move immediately.
How much would be my minimum price to accept to get up? Let’s say it’s 10 €. For less than it I wouldn’t move.

Now, how much is my maximum price I would pay someone else to raise the volume for me? maybe 5 €?

Then, for me the formula is like this: benefits (to raise the volume) = 5€ < Costs (to raise the volume) = 10 €
So, it would be better to stay sit.

The idea to calculate costs and benefits to describe the human behaviour may look strange.  But:
the Nobel prize Milton Friedman explained that you don’t need to think that people do these calculations but you can make forecasts based on the assumption that people decide as if they did these calculations (in the same way as billiard champions play using the physic laws even if they don’t know them).

This is of course just to give a guide, economic models. Many behaviours cannot be explained by the theory, for example why to vote at the elections, why to become donors, etc. even if they can be partly explained by the common good.