Mapping Hacks

10

|

Chapter 1, Mapping Your Life

#2 Route Planning Online

HACK

Turn Right, Gone Wrong

A company’s board meeting had to be postponed, as most of the board

members did not arrive in Cardiff on time, because the driving directions did

not take into account the Severn Bridge and took them from Bristol around

the Severn estuary via Gloucester. A salesman missed out on landing a deal

with his blue chip customer as he arrived too late at the meeting to sign the

contract. The right turn he had to take according to the directions was not

there. On their way to visit their daughter’s new house in Kingston, Dorset,

her parents found themselves in Kingston, Devon instead.

These ill-advised travelers all followed driving directions from various online

mapping services available on the Web today. Although many people suc-

cessfully rely on these services on a daily basis, things sometimes go wrong.

Then, it is neither the person in the passenger seat reading out the instruc-

tions that is to blame, nor the online mapping service: their driving direc-

tions come with elaborate disclaimers to avoid any liability.

Then what is the source of these problems? Of course, many problems occur

at the geocoding stage when entering ambiguous address details that have to

be converted to machine-readable coordinates. But focusing on route calcu-

lation alone, three groups of problems can be observed in ascending order of

severity: ...