Understanding Data - Data Points: Visualization That Means Something - page 4

Now you have more than just a moment in time. You have several moments,
and together they represent the part of the wedding when my wife first
walked out, the vows, and the tea drinking ceremony with the parents and
my grandma, which is customary for Chinese weddings. Like the first photo,
each of these has its own story, such as my father-in-law welling up as he
gave away his daughter or how happy I felt when I walked down the aisle
with my bride. Many of the photos captured moments that I didn't see from
my point of view during the wedding, so I almost feel like an outsider looking
in, which is probably how you feel. But the more I tell you about that day, the
less obscure each point becomes.
Still though, these are snapshots, and you don't know what happened in
between each photo. (Although you could guess.) For the complete story,
you'd either need to be there or watch a video. Even with that, you'd still see
only the ceremony from a certain number of angles because it's often not
feasible to record every single thing. For example, there was about five minutes
of confusion during the ceremony when we tried to light a candle but the
wind kept blowing it out. We eventually ran out of matches, and the wedding
planner went on a scramble to find something, but luckily one of our guests
was a smoker, so he busted out his lighter. This set of photos doesn't capture
that, though, because again, it's an abstraction of the real thing.
This is where sampling comes in. It's often not possible to count or record
everything because of cost or lack of manpower (or both), so you take bits and
pieces, and then you look for patterns and connections to make an educated
guess about what your data represents. The data is a simplification—an abstrac-
tion—of the real world. So when you visualize data, you visualize an abstraction
of the world, or at least some tiny facet of it. Visualization is an abstraction of
data, so in the end, you end up with an abstraction of an abstraction, which
creates an interesting challenge.
However, this is not to say that visualization obscures your view—far from
it. Visualization can help detach your focus from the individual data points
and explore them from a different angle—to see the forest for the trees, so
to speak. To keep running with this wedding photo example, Figure 1-3 uses
the full wedding dataset, of which Figure 1-1 and Figure 1-2 were subsets of.
Each rectangle represents a photo from our wedding album, and they are
colored by the most common shade in each photo and organized by time.