GRAPHICS GUIDELINES

MUSE/CE 11B

Anagnos/Williamson

From Pfeiffer, W.S. 2003. Technical Writing: A Practical Approach. 5th Edition. Prentice Hall. New Jersey. 709 pp.

Why use graphics?

Simplify ideas Reinforce ideas Create interest Universal appeal

General Guidelines to Follow When Using Graphics

1. Determine the purpose of the graphic. The answer affects the type of graphic used, and whether special fonts, symbols or colors will be needed.

2. Evaluate the accuracy and validity of the data used to make the graphic. Be sure to check the accuracy, to verify the source, and be check for flawed scales or images.

3. Refer to all graphics in the text of the document.

General Guidelines to Follow When Using Graphics

4. Determine where and how to place the graphic in your document: landscape or portrait; foldout or not.

5. Avoid clutter by keeping the graphic simple. Omit irrelevant information. Provide white space.

6. Include titles, notes, keys or legends, and source data for every graphic. NOTE that figure headings can be above or below the graphic, however table headings are always at the top.

Pie Chart Guidelines

1. Use no more than 6 or 7 divisions. In general, the fewer the better.

2. Move clockwise from 12:00 from the largest to the smallest wedge.

3. Use pie charts especially for presenting data in percentages or for presenting financial data. Always verify that the percentages total 100% or that the cents add up to 100.

4. Be creative but stay simple…you can explode a pie, show a pie within a pie, shade a wedge, omit one wedge, or use a simple pie for emphasis.

5. Place wedge labels inside or outside of the pie, whichever is the least cluttered.

Pie Chart Examples

Bar Chart Guidelines

1. Limit the number of bars. 2. Show comparisons clearly. If the bars are too close, or the

bars are of a similar length, the impact of the data comparison will be lost. Alternatively, avoid use to bars for data that are of a different magnitude (e.g., 100 vs 3,000).

3. Keep the bar widths equal and adjust the space between bars using one of three ways: no space; equal space but less than a bar width; variable space (to reflect data gaps as when graphing time).

4. Arrange the order of the bars in sequential order (i.e., to show a trend) or in ascending/descending order (i.e., comparing from highest to lowest).

5. Use segmented or grouped bars to display multiple trends.

Bar Chart Examples

Line Chart Guidelines

1. Use to display trends between two variables. The vertical (y-) axis is used for the dependent variable; the horizontal (x-) axis is used for the independent variable. NOTE that the dependent variable is affected by changes in the independent variable (e.g., rain intensity affects streamflow).

2. Verify data for accuracy, and the chart for clarity. Start scales at zero; make chart lines > the axis lines; maintain a vertical to horizontal ratio of axis lengths that makes sense (V:H if 3:4 is common).

3. Avoid placing numbers on the line chart. Keep it simple and uncluttered.

4. Limit the number of lines to 4 or 5 lines per chart. This will present confusion.

Line Chart Examples

Technical Drawing Guidelines

1. Keep them simple by limiting the amount of detail to only that needed to serve the purpose of the graphic.

2. Label all parts well. 3. Select the most appropriate view: exterior,

cross-section, exploded, cutaway, plan, or other.

4. Use legends for complex drawings to avoid over labeling and confusion.

Summary

Keep it simple Keep it accurate Label all components Provide a caption Refer to it in the text Provide a reference Place it in the right location in the report