Box plots

CDP Data Visualization enables you to create Box Plot visuals.

A box plot visual displays the distribution of data values. The box represents the bulk of the data (25th percentile through 75th percentile), and whisker lines represent statistical minimum and maximum values.

This example uses the 2012 and 2013 API Scores for California Schools.

We are working with the dataset School Performance, built on the a datafile that contains the California School APIs from 2012 and 2013. Note that the range of possible scores varies from a low of 200 to a high of 1000. The statewide API performance target for all schools is 800. For an overview of shelves that specify this visual, see Shelves for box plot visuals.

  1. Start a new visual based on dataset NYC Taxi Data; see Creating a visual.
  2. In the visuals menu, find and click Box Plot.
    selecting box plot chart type
    selecting box plot type
  3. Note that the shelves of the visual changed. They are now X, Y, Dimension, Measure, and Filters.

    The mandatory shelves are:

    • Dimension: specify one dimension for grouping the box plot
    • Measure: specify the measurement for box plot calculations
    shelves of box plot visual type
  4. Populate the shelves:
    1. Place the field Dname (district name) on the Dimensions shelf.
    2. Place the field Api13 (API obtained in 2013) on the Measure shelf.
    3. Add the field Cname (county name) to the Filters shelf, and select a single value. We used Santa Clara.
    4. Add the field Stype (school type) to the Filters shelf, and select the value H, for Highschool.
  5. [Optional] Alias the shelves.
  6. Click Refresh Visual.
    basic set-up for box plot shelves

    The new box plot visual appears.

    simple box plot visual
    tooltip of a box plot
  7. Change the title to High School Performance - Box Plot.
    • Click (pencil icon) next to the title of the visualization to edit it, and enter the new name.

    • [Optional] Click (pencil icon) below the title of the visualization to add a brief description of the visual.

  8. At the top left corner of the Visual Designer, click Save.
  9. At the top left corner of the Visual Designer, click Close.

If you wish to generate a horizontal box plot visual, see the instructions in the article Making box plots horizontal.

To adjust the box plot display, check all the available settings for this visual.