Relating parts of the data to the whole

As you explore and analyze data, you'll often want to understand how various parts add up to a whole. For example, you'll ask questions such as:

• How many patients with different admission statuses (in-patient, out-patient, observation, ER) make up the entire population of patients in the hospital?

• What percentage of total national sales is made in each state?

• How much space does each file, sub-directory, and directory take up on my hard disk?

These types of questions are asked about the relationship between the part (patient type, state, and file/directory) and the whole (entire patient population, national sales, and hard disk). There are several types of visualizations and variations that can aid you in your analysis.

Stacked bars

We took a look at stacked bars in Chapter 1, Creating Your First Visualizations and Dashboard where we noted one significant drawback: it is difficult to compare values across categories for any bar other than the bottom-most...