To a Journalist, “it’s a small world,” after all.
You are walking through Kmart (or Country Road if you are a snob), when you run into your cousin from across town….
You are walking through Kmart (or Country Road if you are a snob), when you run into your cousin from across town….
“A … misconception of
probabilities arises from the random encounters one may have with relatives or
friends in highly unexpected places.
“It’s a small world!” is often uttered with surprise.
But these are not
improbable encounters….
It is just that we are
not truly testing for the odds of having an encounter with one specific person,
in a specific location, at a specific time. Rather, we are testing for ANY encounter, with ANY person we
have ever met in the past, and in ANY place we will visit during the period
concerned.
The probability of the
latter is considerably higher, perhaps several thousand times of magnitude of
the former.
When a statistician
looks at data to test a given relationship, say to ferret out the correlation
between the occurrence of a given event, like a political announcement, and
stock market volatility, odds are that the results will be taken seriously.”
(Fooled by Randomness – Taleb p 148).
Journalists DAILY provide us with reasons that the market
moved up 2%, or crashed 3%. All
noise of course on a short-term basis.
But they are just reacting to the any
relationship, small world sample, and making any connection.
In fact, “Causality
can be very complex. It is
difficult to isolate a single cause when there are plenty around. This is called Multivariate Analysis.” (Fooled by Randomness, p197). To imply causality, ALL possible reasons for the stock move
must be looked at, both in isolation and jointly, with calculated confidence
levels to arrive at the conclusion.
I studied Statistics a bit at University, and whilst I
forget WAY more than I remember, I DO remember that those Multivariate Analysis
calculations were pretty damn complex.
I’m also sure the media is not running those before they make their
claims!!! (Remember what I said
about statistician’s results, and being taken seriously – I am no
statistician!)
Consider….
…the three major
indices rebounded on Friday thanks to a solid GDP report…
The bond
markets, meanwhile, struggled in Friday trading on the news that “Bond King” Bill
Gross is leaving
PIMCO, the firm he founded, for Janus Capital.
When you look for any relationship to explain data, it will often
amaze people.
Couple that with the human need for a “story or narrative”
(Nick and Jarrod did a webinar on this which I thought was great) and you have modern
media defined to perfection.
I was in NY recently, and saw the block-long lines for tickets
to the upcoming “Star Trek Convention” getting airtime on the Midday News. The Dow was down that day a little….
I can see the headlines now….
DOW PLUNGES 2% AS WALL STREET TRADERS QUEWE FOR STAR TREK TICKETS!!
(Hype – Noise – Noun – Verb – Random Event = Headline).
Finally, do you remember those drawings as a kid where you
connected the numbered dots to reveal a picture? 1 to 2 to 3 to ….. 45.
And you had a BEAR drawn!!!
(Picture included for illustrative purposes only – below).
You only had a bear because someone led you to it. Without the
numbers, there was any combination of other pictures, or simply a messy ball of
string and randomness. (Which is
YOUR narrative?)
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