Exploring Data Visually - Data Points: Visualization That Means Something - page 480

when it's time to visualize, they realize they either need more data or their
data doesn't work with the chart they want to make.

The common mistake is to form a visual first and get the data later. It should
be the other way around—data first and visualization follows.

Often, getting the data that you need is the hardest and most time-consuming
part of the visualization process. In school, data is handed to you formatted
the way you need so that you can easily load it into the software of choice,
but this is hardly ever the case in practice. You might need to scrape data from
a website, access an API, or derive values from existing data.

Note: I sometimes spend most of the time
gathering data and little time visualizing it.
Don't be surprised if you have to do the same.
Totally normal.

For example, you might have a list of addresses, but to map
them, you need latitude and longitude coordinates. Or you
have observations for individuals of a population, but you
might be more interested in subpopulations.

Programming can be helpful in this case to automate parts
of the process, but there are a growing number of click-and-
play applications to manage data, too.

Note: See Chapter 7, “Where to Go from Here,”
for tools and resources to work with and visual-
ize data.

When you have data you want to explore, pause for a sec-
ond to consider what values represent, where the data is
from, and how variables were measured. Essentially, apply
everything you learned in Chapter 1, “Understanding Data.”

WHAT DO YOU WANT TO KNOW ABOUT YOUR DATA?

Imagine you have some data to explore. Where do you begin? The answer is
easy if you have only one data point. You can just read the value, and most of
your findings, if any, will come from outside information and additional data.
On the other hand, when you have a dataset with thousands or millions of
observations—think spreadsheet with a lot of rows—it can be challenging
and often intimidating to figure out what to look at first.

This is where the phrase “drowning in data” comes from. You stare at a bunch
of numbers on your computer screen, and values start to blur together the
longer you stare. Soon all you see is a blob of data that feels suffocating, but
wait; there's hope. Take a step back. Breathe.

To avoid drowning in data, you learn to swim. When you learn to swim, you
start at the shallow end and work your way toward the deep end. If you're