Regarding
this most recent incident, it is of particular interest that social media provided
the most detailed account of the Mayor’s evening out. Posts on Twitter, several including links to
video and photographs, tracked his movements from the start of the hockey game
to his confrontation with security, alerted followers to his late night visit
to City Hall (What was that mysterious burning rubber smell detected by
security there? Why is that not mentioned in the traditional media?), and
established his early morning presence at the Muzik nightclub. In this case, it seemed that Twitter was
breaking the news, and that the traditional media were playing catchup. As reports appeared in the media the next day
some posts on Twitter accused traditional outlets of not telling the complete
story!
All of this
made me think of Twitter as representing reality in what connectionist
cognitive scientists call a coarse code.
Many artificial neural networks generate highly accurate responses by
pooling the signals of individual elements, where each individual element has noisy,
sketchy, or inaccurate information about what is going on. The ‘coarseness’ of this type of
representation is reflected in the fact that every processor inside the network
is an inaccurate detector. The surprising
power of this representation comes from the fact that if you combine all of
these poor measures together, a highly accurate measure is generated.
For coarse coding
to work, the individual (inaccurate) measures generally require two different
properties. First, different measuring
elements must have overlapping sensitivity: many of them will be measuring
similar things. Second, different
measuring elements must also have to have different perspectives on what is
being detected. In short, their
sensitivities overlap, but are not identical. When these two properties are true high
accuracy can be produced by combining measures.
This is because if each detector has a different perspective, it will be
providing different ‘noise’ than is provided another. Combining the different noise from different
detectors will tend to cancel it all out.
What remains is the amplified ‘signal’ – the ‘truth’ – that is also
being sensed to a limited extent by the various processors in the network (due
to their overlapping sensitivities).
Each
individual tweet on Twitter can be viewed as some information being provided by
an inaccurate detector. If the sources
of a large number of these tweets have slightly different perspectives, or
provide different kinds of information (statements vs pictures vs videos), then
their combined effect provides information that has a strong sense of accuracy.
Not
surprisingly, researchers interested in Big Data are actively exploring this
characteristic of social media. For
instance, some researchers are using the content of tweets to
predict the results of elections, although the accuracy of this approach is
subject to a healthy debate.
Importantly, the accuracy of such predictions requires that the two key
properties of coarse coding (presenting information that is similar, but
different) be true. When these
properties are not true – for instance, when many people retweet the same
information, so that different perspectives are not provided – social media
can misinform, as shown by Twitter being a continual source of celebrity death
hoaxes.
To me, the
parallel between tweets and successful coarse coding in artificial neural
networks clearly indicates that Twitter can be a source of a great deal of
accurate information, and makes me reflect on how neural network paradigms
might be tweaked to explore tweet contents.
The
parallel also makes me think that if I was a politician seeking reelection –
particularly one who is such a notorious celebrity that my frequent encounters
with the public immediately appear on social media – I would strive to be on my
best behavior. The image of me emerging
from all of those Tweets might be more accurate and telling than the one that
the traditional news media feels safe to publish!