Category: Lead Story

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Corona Virus infection’s growth is not “exponential”

Yesterday night, Roberto Speranza, the Italian Health Minister, said to TG4 (the news programme of a National broadcaster) that the Coronavirus spreading in Italy is – or it has been -? “exponential”. As a matter of fact, this is not correct, as “exponential” has a specific mathematical meaning that does not match with the data provided by the Italian Government itself. Moreover, talking about “exponential growth” without indicating the exponent and specifying whether it is whole or fractional, does not allow the listener to understand what is the real “steepness” of the curve to which we are referring. Finally, at most, we can speak of an exponential trend in relation to a stretch of the curve, certainly not in relation to the curve itself. Unlike a mathematical function, in fact, the data on contagion are conditioned by variables? that vary (how many probes I did yesterday, how many I do today and how many I will do tomorrow, on which population I perform the analysis etc. etc.). In other words, the trend of the contagion curves (net of all the questions about the composition of the sample) has a (limited) descriptive capacity of the past, but it can hardly give indications about the future.

Raising this issue with a fellow journalist I got this answer: “stop being a semantic prick! People are not read in mathematics and they know that when we use “exponential” we do it as a synonym for “very quick and fast grow”.

Well, maybe I am a “semantic prick” – aren’t we, lawyers?  – but when hard decisions such as putting the whole Italy in quarantine have to be taken, I would expect the decision-makers to ground their assessment on solid basis rather than on a sloppy use (and understanding?) of data and information.

This is not to say that the decision to quarantine Italy is wrong (I neither have the knowledge nor the competence to judge it.) I only point out that there might not be a cause-effect relationship with a (good) decision and the reasons that backed it.

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Virus, Statistics and Videogames

It seems to me that the way the Corona Virus numbers are used in this phase of global hysteria does not help in the understanding of the scenario.

Animations and “infographics” about the spread of contagions, deaths counts or the speed at which the virus propagates are ubiquitous, but the criteria used to produce these materials are hardly known, and sometimes there is a suspicion that some of them lack real basic knowledge of how statistics work.

I prevent an (easy) objection: it is true, I am a jurist and not a statistician, so I am not qualified to speak with scientific competence on the subject.

That is true, and indeed I do not intend to. I only use what I learned in mathematics between high school and university and what I studied in statistics by collaborating on the Italian edition of the classic by Darrell Huff, How to lie with statistics, edited and translated by Giancarlo Livraghi (who, as a great advertising man, knew the subject perfectly) and by Prof. Riccardo Puglisi (who, as an economist, is equally well versed on the subject).

I do not offer “truth”, therefore, but only doubts in search of answers.

Firstly: unifying the various categories of the deceased makes the sample unbalanced and calculating the mortality rate on an undifferentiated population provides an unreliable result. To establish the death rate of the virus, one should at least differentiate who had other pathologies on the consequences of which the virus was superimposed, from those who were sick of something else but did not know it, from those who were in particular conditions that favoured the expansion of the virus (immunodepression from hyperactivity, for example). This article goes in the right direction, even if the methodological problem of how to use statistics remains.

Secondly: it is one thing to analyse a statistically valid sample; it is another to analyse an unbalanced sample. In other words: if I look for the supporters of a football team in the supporters’ curve, I obtain a clearly different result than if I use a sample – depending on the level of the team – built on a city or national basis. Unbalanced champions can also serve, but you need to be clear about the limits of the knowledge they generate.

Thirdly (and consequently): even transforming the absolute values of deaths and infections in various countries into percentages without adopting weights is methodologically wrong. To say – as Il Giornale does – that the mortality rate is 4% out of 3,858 cases induces an incorrect generalisation when comparing the “raw” ratio between the number of cases and deaths.

Moreover, and concluding: as long as there are no numbers large enough to obtain statistical significance, one should be very cautious in spreading them. If 7 out of 10 or 490,000 out of 700,000 people give a particular answer to a questionnaire, in both cases, we can say that 70% of the respondents pronounced in a certain way. But (without prejudice to the need for a statistically valid sample) each case clearly has a different explanatory power. It would be useful to know, for example, whether the numbers used in a study like this are still too low to be statistically valid or not. In the first case, it would be “only” a frozen-frame of an upgoing video; in the second it would provide information on overall value.

Rereading Darrell Huff’s book, therefore, might not be a bad idea.

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Even Thumbs Deserve Privacy

This article published by Il Fatto Quotidiano is illustrated by a photo that portrays a policeman from the mobile team of Rome and an arrested man whose image is blurred. Not, as you might think without seeing it, on the face that also has a winking expression towards the photographer, but on the hand that is shaped in the pose (the thumb raised) universally become synonymous with “I like it”.

The expression of the arrested subject is disturbing because it is no different from that of a star crossing the red carpet of a film festival or a sports champion celebrating a victory. And it reinforces the mistaken perception – further distorted by television series such as Narcos and Gomorrah – that there is an aesthetic of evil in the name of which, by committing atrocious acts, one can become famous.

This “right thumb” attached to the hand of an ordinary person accused of a crime obviously means that from the desire for a “moment of glory” experienced in film/television fiction we have moved on to the lust of a celebrity at all costs, including that of becoming a protagonist of a crime story.

I don’t know who (whether the photographer or the newspaper) has made the choice to blur the anatomical detail of the arrested, but in both cases I can’t find a reasonable explanation, except for the one that, by now, even the thumbs have a right to their privacy.

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The Buzz Aldrin’s Glass

Do you see this glass of water in front of us? To a pessimist is half empty… to an optimist is half full… to an engineer is just much too big.

This is a quote form an interview that Buzz Aldrin gave to the Italian national broadcasting service on July, 21 2007.

No need for further explanation…

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Dieselgate Volkswagen’s Advertising Strategy: Thou Shalt Not Take the Name of the Brand Invain

Yesterday I’ve stumbled upon the first Volkswagen’s TV commercial of the after-Dieselgate scandal.

At first sight, there is nothing different from the previous campaign: a car, its technical specification, the unique selling proposition and, final, a company full-screen logo. But, as they say, the devil is in the details.

The commercial only mentioned the car model’s name without any reference to the word “Volkswagen” during the whole duration and, when the logo-moment came, neither the name of the car-maker nor the claim “Das Auto” went on screen.

Volkswagen’s strategy to limit the lose of its market share, thus, seems to be oblivion-inducing based. Let people forget about the cursed name for a long enough time, to come back when? Dieselgate would have been buried in the past and the brand name can shine again.