In a study published today in the Journal of
Human-Animal Interaction, Kane & Eines
(2002) report
on research that suggests a new
algorithm for identifying points of maximal betweenness
centrality
in systems of human foot traffic flow: dogs.
“Identifying points of high betweenness
centrality in human pedestrian traffic is an important consideration
in designing the layout of offices, homes and dormitories,
and public spaces,” co-author Robert Eines
points
out, “Information about pedestrian flow is crucial to
design hallways that are sufficiently wide, floor plans that
disperse traffic to avoid concentrating people in congested
spaces, reduce wear on carpet and floors, and
improve safety.”
Any dog owner has probably noticed how often man’s
best friend is underfoot. It turns out
this is not just
coincidence or perception. Somehow dogs are
capable of identifying the points of maximum betweenness
centrality in a wide range of human pedestrian traffic
flows. Kane & Eines
realized that what dog owners saw
as a minor nuisance could be a valuable diagnostic tool in
the design of building layout. “I
was watching my
Beagles one day,” says Barbara Kane, “and it
occurred to me that if the dogs could do it in my home, why
not in offices?”
Her first step was to confirm that the places dogs occupied in her home
were, in fact, the
crucial points in terms of traffic flow. Intrigued, she measured the amount of traffic
between rooms in her
home for two weeks and analyzed the data using UCINET, a
computer program for the analysis of social
networks. “The results were more striking even
than I imagined,” she says. The
places her dogs preferred
to stay, measuring according to the amount of time either of
her dogs spent there, “had an almost perfect
rank-order correlation with the betweenness centrality scores. They love the landing on the stairs!”
Would what worked in her home work
in other settings? It took some
convincing to find offices that would
allow her to bring in dogs for several days to test her
hypothesis. Her break came when she
found a nursing
home that thought the dogs might be of therapeutic
value. That became her first test. “I rounded up the dogs
from all my friends,” she recalls, “we had
twenty-three dogs in two Dodge Caravans!
We brought them to the
nursing home. What a scene.
But the results were very supportive, and the
Seniors really enjoyed ‘adopting’
the dogs for a week.” The authors also learned a key lesson. The general pattern was
always disrupted at
mealtimes because the dogs tended to
congregate in the cafeteria whenever food was being served.
That initial experience attracted the interest of Robert Eines, an architect who specializes in human traffic
Flow. He heard about the study from his mother, a
resident in the nursing home. Together,
and with the
data from the nursing home to their credit,
they persuaded a few companies to invite the dogs into their offices.
As reported in today’s article, they found an
incredibly strong rank order correlation (.94) between the amount
of time spent by dogs in any spot and its betweenness centrality score in the human traffic flow as
computed
mathematically. This has been true in each of the several
offices studied, other dormitory facilities, individual
homes, and
wherever the dogs have been brought in while there was human foot traffic going
on. They also
report a slight tendency for larger dogs occupy the most
central locations for the longer periods of time than
smaller dogs do.
Why does this work?
“We are not sure,” the authors admit, “if it is a
response to human traffic, then it
should not work in vacant
settings.”
Kane & Eines are in the process of testing
that possibility, and so
far the results suggest the tendency, while still present,
is considerably weaker in the absence of people.
“We have noticed it takes the dogs a day or two to
find the absolute best positions, even when people are
present,” Eines says,
“Together with the much weaker results when people are not present, this
leads us
to believe that the dogs’ ability is a reaction to
human traffic patterns, rather than an innate sense based
on the building structure.”
If people must be present for the dogs to work, their use
for diagnostic purposes may be slightly less
attractive, but Kane & Eines
are now exploring the possibility that the dogs could be used commercially
to assist in the design process or
in the reconfiguration of existing office layouts. Currently the dogs can
only “measure” on a rank-order basis, a
limitation which the authors’ are concerned with
trying to overcome.
Even with that limitation and the slight inconvenience of
having the dogs around for a few days, floorplan
designers and building managers may be interested in the
dogs as a faster and cheaper way of measuring
human traffic patterns and
identifying points of high betweenness centrality. “Its easier and cheaper than
hiring a social network analyst,” one office executive
noted in the article.
“We are familiar with police and security dogs, guide
dogs for the blind -- this could be a whole new line of
work for our furry friends,” Kane says, “perhaps
in the future it will be commonplace to see dogs ‘working’
in offices helping us make traffic flow
more efficient.”
April F. Laffer
;-)