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Language: en
you're watching a Nova science Now video
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podcast in an election year people might
disagree about who makes the best
candidate but you don't hear much
argument on the merits of democracy that
millions of average people can together
make a wise decision it wasn't always so
in the early 20th century this
controversial Englishman Sir Francis
gton tried to statistically test where
the mobs of common folk were capable of
choosing well and as our musical
correspondent Rob morsberger tells us
what Sir Francis actually found was that
mathematically at least there's often
wisdom in a
crowd Sir Francis gson was a
nobleman and scorned the common masses
he thought that votes of governance
should be left to higher
classes he'd prove with all the data
from a contest
inescapable of guessing even simple
things the commoners were
incapable ladies and gentlemen step
right up what kind of contest might it
be guess the ox's white and see guess
the weight correctly and win a prize
it's 100 said a little one that's much
too light at least a ton an eager crowd
queued up to play 800 made a guess that
day so we had 800 data
points and now the ox's white is exactly
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97198 there are no
winners so Francis knew the
would never guess the weight how might
they judge important things if left to
meet that
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fate with mathematics he would show how
far they went astray but in the end his
theory was in total disarray because a
curve of all the guesses oh that curve
it's the cumulative distribution
function of the normal
distribution sorry that's what it's
called because grapping all the guesses
and determining their mean I think he
was talking about the
median and determining their median he
showed that if the crowd were one its
estimate is key he showed that if the
crowd were it's the is
King King yes that's because while no
individual guessed the actual weight the
average of all the guesses is exactly
right the average will generally be
better than a randomly selected
individual guest the average of the
masses assures us of success I think he
was talking about the medium and the
larger the number of guesses we toss in
the more likely we are to get the right
answer about the oxin this premature
prognostication they cannot help but
gton should have gathered more data
before he went shooting his mouth off
francis's hypothesis was rocked by ignor
he lost the proof he had he found the
wisdom of
the if you have a group of people and
they each have tiny bits of information
then you can learn a lot if we could
just gather all of those bits together
it's just like Wikipedia well this isn't
exactly like Wikipedia no it's a little
bit different it could maybe be
Wikipedia oh you don't even need to be
an expert but if you know something then
you're able to contribute and that entry
is able to be that much more informed
another sample of this Fair Who Wants To
Be A Millionaire yeah the audience
Lifeline if a person feels like they
can't answer the question by themsel ask
the audience the audience is right over
90% of the time there you go how about
that Gman it's the wrong Gman sorry one
by one not too but every guess it plays
its part and when you add them up you'll
find
the wi of
the for more fun science stories watch
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