Jakarta is smaller than it should be

Jakarta is smaller than it should be

Robert Kelly, Jakarta

By some measures, Jakarta is the fourth-largest city in the
world. Traffic congestion, air pollution, over-crowding, crime
and rising property prices all attest to its rapid growth, and
all are problems the capital's residents have to confront daily.

So it might surprise you to learn that Jakarta is actually too
small -- 4.3 million people too small.

The source of this uncomfortable revelation is a phenomenon
called Zipf's Law. It states that the largest city in a country
tends to be twice as large as the second-largest city, three
times larger than the third-largest city, four times larger than
the fourth-largest city, and so on.

Zipf's Law is very common, and is found in countries as
diverse as the United States, Argentina, Pakistan and Japan.
Where the Law doesn't hold, it's usually because the capital city
is larger than expected: Notable instances include London, Paris
and Mexico City.

All of which makes Jakarta highly unusual -- for Jakarta is
actually smaller than Zipf's Law predicts.

Jakarta contains over 9.4 million people. According to Zipf's
Law, it should be double the size of Bandung, five times larger
than Surabaya, nine times larger than Medan, twenty times larger
than Samarinda. In fact, it falls short in every single case.
Compared with Medan, for example, Jakarta is barely half the size
it should be.

If Java is taken as the reference point, rather than the whole
of Indonesia, the same pattern emerges. Jakarta is four times
larger than Semarang when it should be six times bigger. It
should be eleven times larger than Tegal, yet is only five times
the size.

Of course, it is possible that Indonesia is unique in some
way: That Zipf's Law doesn't apply and that Jakarta is not "too
small". However, this seems unlikely when one considers the
diversity of countries where the Law does apply: Why should it
apply to the U.S. and Pakistan and not to Indonesia?

It is also possible that Zipf's Law is unimportant, a
statistical oddity that countries can safely ignore.
Unfortunately, the latest academic research suggests that there
are good reasons why urban systems tend to evolve towards Zipf's
Law. It appears that Zipf's Law represents an "efficient"
configuration of cities, in the sense of maximizing a nation's
economic output subject to demographic and transport constraints.

In fact, in all likelihood Indonesia is merely in a state of
transition, moving towards Zipf's Law but not quite there yet. If
that is the case, Jakarta can expect plenty more growth to come.

To properly conform to Zipf's Law, Jakarta would have to grow
by a staggering 46 percent -- roughly 4.3 million more people
packed within the city limits! And that assumes that other cities
remain at their current sizes. If they themselves continue to
grow, Jakarta's population would have to grow yet more to
compensate.

Clearly, over the next few years Jakarta's growth is likely to
be influenced by a host of other factors, not least the
performance of the national economy and government policy towards
regional development.

Nonetheless, Zipf's Law does give pause for thought. Next time
you find yourself stuck in one of Jakarta's endless traffic jams,
console yourself with the knowledge that Jakarta is actually less
crowded than it should be.

The writer is a freelance British journalist living in
Jakarta. and can be reached at robert_em_kelly@yahoo.co.uk