Data Displays
Data displays show quantitative information by transforming textual elements, usually numbers, into images.
-Data displays are extra-level and rely on non-textual signs like lines, bars, circles, shading, dots, and color
-Text plays a secondary role in data displays
Why are data displays useful?
1.) They are a visual representation of numerical data
2.) They show complex sets of data in a easier to read format
3.) They give readers a top-down view of the trends and relationships of the data
Data displays greatly enhance our ability to compare numbers.
Depending on the rhetorical situation, there are different types of data displays that are most effective.
-Different things about the data can be discovered by shaping them in a visually effective way
Process Example
In this example Ed is asked to make a data display for the membership of an organization over the last ten years.
This example emphasizes the importance of:
· Analyzing the rhetorical situation
· Invention
· Revision
· Visual editing
Vocabulary of Data Displays
Textual Elements only play a small role in data displays since they primarily focus on sign systems. Textual elements include labels, titles and legends. They add descriptive information that can both help and hinder the data display.
Spatial Elements include the size, shape and orientation of the display.
Conventional forms:
· Pie Charts: show parts of the whole
· Bar Charts: create a grid for plotting data based on two variables (one is usually time). Simple bar charts show data belonging to a single group, while complex bar charts show data for more than one group of data
· Line Graphs: show the same type of data as a bar chart, but the display consists of lines connecting the data points and can help easily show change over time
· Scatter Plots: show relationships between variables that are often unrelated to time
· Data Maps: reveal information about a given location, and are arranged depending on the space they represent and the relative location of the data in that space
· Gantt Charts: display time in carrying quantities according to the amount needed for a given task or project
· Graphical Matrix: enables readers to see patterns across the whole data set as well as to access individual pieces of data
Certain conventions will be more suitable than others for a given set of data depending on the rhetorical situation.
Graphic Elements control the texture, weight, and color of the lines, bars, plot frames, tick marks and a variety of other forms. Graphic elements alone represent the data of a data display, although often rely on textual elements to help define them.
-Gridlines, plot frames, tick marks, background shading, and color are elements that help define the data
Applying the Cognate Strategies
Arrangement involves choosing an effective conventional data display and the order and placement of the data within this framework.
Emphasis can be created by stretching the plot frame in one direction, the thickness of lines, color, etc.
Clarity is key to an effective data display. If the display does not make the data from a table more clear, than it is not effective.
Conciseness requires that the data display be direct and easy to understand, and not include extra embellishments that serve no purpose.
Tone shows the voice or attitude the display reveals. Is the data display formal, technical, authoritarian, friendly, accessible or humorous? Picking the right tone depends on the rhetorical situation.
Ethos requires that the display is honest, and displays the information so readers have an accurate story about the data.