

The Magical Number 7 plus or minus 2 - gabea
http://en.wikipedia.org/wiki/The_Magical_Number_Seven,_Plus_or_Minus_Two

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Jun8
I have always been somewhat skeptical of the fact that this number coincides
so nicely with the number of digits in a phone number, which the subjects (I
presume to be from the US, I know, I have to track down and read the paper)
are highly trained to commit to short term memory.

Does anyone know of similar finding were found in experiments with diverse
cultures?

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o_nate
This is kind of a chicken-and-egg problem, isn't it? Which came first: the
ability to remember 7 digits, or the decision to make phone numbers 7 digits
long? It seems more likely that 7-digit phone numbers became common because
that was the highest number of digits that most people could remember.

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erikano
I believe that there is some truth to the claim that the length of a phone
number affects our ability to remember numbers of that length; in Norway, we
have 8 digits in our phone numbers.

A couple of years ago, I decided to try and remember as much of Pi as I could,
and I found that precision to which I could remember it, was in fact 8 decimal
digits. Even though I have only been asked to recite as much of Pi as I could
remember _once_ during the last year, and I seldom actively try to remember
it, whenever I come to think of Pi, _3.14159265_ usually pops into my mind.

However, whereas I remember telephone numbers either grouped on the form _12
34 56 78_ ( _twelwe-thirtyfour-fiftysix-seventyeight_ ) or _123 45 678_ (
_hundredandtwentythree-fourtyfive-sixhundredandseventyeight_ ), I remember Pi
as a sequence of digits ( _three-comma-one-four-one-five-nine-two-six-five_ ).

Edit: The two ways of grouping the digits in a phone number that I mention
here, is the way that phone numbers are usually written here in Norway. Often,
landline phone numbers are written on the form _xx xx xx xx_ and cellphone
numbers on the form _xxx xx xxx_. (Additionally, if I remember a phone number
on one form, and someone else says the same number on the other form, I find
it hard to tell whether we are speaking of the same number).

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mfukar
Just as an anecdotal piece of info: most musicians accept that the human brain
can keep track of eleven notes. Beyond that, you can change the scale
progression and the transition will be (relatively) smooth to the human ear.

~~~
bryanh
Perhaps you could clarify or point me to some more information on this? Even
as a (somewhat amateur) jazz musician, musical pivots have always eluded me.

~~~
mfukar
I've been searching for an interview with Jimmy Page, where he mentioned this
and it's the first I've heard of it, but to no avail. Hence, 'anecdotal'. If I
find it, I'll post it here.

