F5: Data Presentation (tables, graphs, photographs)
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Learning Objectives
- Explain why tables, graphs, and photographs are essential for laboratory reports.
- Identify three common methods of presenting data and how they are best applied.
- Identify features that allow tables, graphs and photographs be effective communication tools.
- Use Excel to make simple graphs and tables.
- Explain how to learn more about presenting data.
Why are Properly Created Tables, Graphs, and Photographs Essential?
Data is at the core of all engineering laboratory reports! Without data, the report is meaningless; therefore, it is essential for authors to present data properly so that the reader can understand the report. Tables, graphs, and photographs are very effective methods of communicating laboratory data. Properly presented data allow the reader to easily find and understand the data.
What Are Three Common Ways to Present Data and How Are They Best Applied?
- Tables:
Show specific quantities well. For example, if we want to know the temperature in 10 major world cities on June 1, a table showing the temperatures in each would be appropriate. Presuming the writer is not establishing a physical relationship between the cities, a graph would not be appropriate. - Graphs:
Show trends or relationships. For example, if we want to know how the temperature in a city varies throughout a year, a graph plotting temperature as a function of the day would be appropriate. There are many types of graphs, but XY Scatter Plots are the most commonly used in engineering laboratory reports. - Photographs and sketches:
These record visual data (not all data is quantitative). For example, if we are trying to characterize the amount of corrosion on a test sample, a photograph may be ideal. In addition to be used to document results, photographs may be included in the “Methods” section to show laboratory equipment, test specimens and/or overall test set-up.
What Features Allow Tables, Graphs and Photographs to be Effective Communication Tools?
To be effective, data must be presented clearly; it must be easy to find and easy to understand.
- First and foremost, writers must understand how the data fits in the context of the report’s objectives. Only once the writer understands what they are trying to communicate can they then determine how to best communicate it to the readers. A good writer learns as they write.
- Follow standard conventions. Readers are expecting certain conventions. It is like driving in the United States – it is expected that you will drive on the right side of the road. Writing conventions allow the reader to quickly and effectively “navigate” the report.
- Useful captions. Tables, graphs and photographs should be able to “stand alone”. Without reading anything else in the report, the reader should be able to look at the data and understand it reasonably well. Captions (verbal explanation that accompanies every table, graph and photograph) should concisely explain the data in the figure.
- Quantitative data. Quantitative data in engineering reports are not numerals, they are measured quantities. It must be clear to the reader what is being measured (e.g. force) and the units of measure (e.g. newtons).
Why Use MS Excel to Make Graphs and Tables?
MS Excel is ubiquitous; therefore, it is important to be able to use it to make basic graphs and tables.
How Can I Learn More About Presenting Data?
There are many texts on creating good tables and graphs, but perhaps the best teacher is to look through engineering textbooks and observe what tables and graphs communicate to you. Pay attention to the details that the author included – do they help you (as the reader), or could they be better? Apply the knowledge you gain from doing this to your own reports.