Tag: Signal v. Noise

Nassim Taleb: The Big Errors of Big Data

bigdatabigerrors_taleb

I am not saying here that there is no information in big data.
There is plenty of information.

The problem — the central issue — is that the needle
comes in an increasingly larger haystack.

***

Nassim Taleb offers another way to look at big data.

We’re more fooled by noise than ever before, and it’s because of a nasty phenomenon called “big data.” With big data, researchers have brought cherry-picking to an industrial level.

Modernity provides too many variables, but too little data per variable. So the spurious relationships grow much, much faster than real information.

In other words: Big data may mean more information, but it also means more false information.

To me, this relates to reading the news.

We’re consumed—bombarded even—by all of this incoming information that’s constructed in a way to capture and maintain our attention. Somewhat counter-intuitively, this distraction offers negative, not positive utility. Not only does it give us easily accessible information that’s full of noise from people that are not deeply fluent in the subject they are talking about but we rarely consider the opportunity cost of this time or the false confidence it gives us (which causes us to take undue risks).

It would be much better to focus our limited attention in two places.

The first, our niche. That is our narrow specialization or our circle of competence. This is after all how we’ll make a living.

The second, on how the world works. These are the time-tested ideas that repeat throughout history and don’t change as time passes.

These are the mental models that you can use to not only better understand how the world works and why people behave as they do, but also to make better decisions.

They combine a narrow specialization with a general view of how the world works. If you further add how to think, now you’re really getting somewhere.

The Problem With Information

Nassim Taleb in Fooled by Randomness: The Hidden Role of Chance in Life and in the Markets:

The argument in favor of “new things” and even more “new new things” goes as follows: Look at the dramatic changes that have been brought about by the arrival of new technologies, such as the automobile, the airplane, the telephone, and the personal computer. Middlebrow inference (inference stripped of probabilistic thinking) would lead one to believe that all new technologies and inventions would likewise revolutionize our lives. But the answer is not so obvious: Here we only see and count the winners, to the exclusion of the losers (it is like saying that actors and writers are rich, ignoring the fact that actors are largely waiters — and lucky to be ones, for the less comely writers usually serve French fries at McDonald’s). Losers? The Saturday newspaper lists dozens of new patents of such items that can revolutionize our lives. People tend to infer that because some inventions have revolutionized our lives that inventions are good to endorse and we should favor the new over the old. I hold the opposite view. The opportunity cost of missing a “new new thing” like the airplane and the automobile is minuscule compared to the toxicity of all the garbage one has to go through to get to these jewels (assuming these have brought some improvement to our lives, which I frequently doubt).

Now the exact same argument applies to information. The problem with information is not that it is diverting and generally useless, but that it is toxic. We will examine the dubious value of the highly frequent news with a more technical discussion of signal filtering and observation frequency farther down. I will say here that such respect for the time-honored provides arguments to rule out any commerce with the babbling modern journalist and implies a minimal exposure to the media as a guiding principle for someone involved in decision making under uncertainty. If there is anything better than noise in the mass of “urgent” news pounding us, it would be like a needle in a haystack. People do not realize that the media is paid to get your attention. (For a detailed explanation on this see Trust Me, I’m Lying) For a journalist, silence rarely surpassed any word.

On the rare occasions when I boarded the 6:42 train to New York I observed with amazement the hordes of depressed business commuters (who seemed to prefer to be elsewhere) studiously buried in The Wall Street Journal, apprised of the minutiae of companies that, at the time of writing now, are probably out of business. Indeed it is difficult to ascertain whether they seem depressed because they are reading the newspaper, or if depressive people tend to read the newspaper, or if people who are living outside their genetic habitat both read the newspaper and look sleepy and depressed. But while early on in my career such focus on noise would have offended me intellectually, as I would have deemed such information as too statistically insignificant for the derivation of any meaningful conclusion, I currently look at it with delight. I am happy to see such mass-scale idiotic decision making, prone to overreaction in their post-perusal investment orders – in other words I currently see in the fact that people read such material an insurance for my continuing in the entertaining business of option trading against the fools of randomness. (It takes a huge investment in introspection to learn that the thirty or more hours spent “studying” the news last month neither had any predictive ability during your activities of that month nor did it impact your current knowledge of the world. This problem is similar to the weaknesses in our ability to correct for past errors: like a health club membership taken out to satisfy a New Year’s resolution, people often think that it will surely be the next match of news that will really make a difference to their understanding of things.)