English 
Technical Writing 
Fall 
As the writer, you have a responsibility to create graphs that accurately portray the information. In this example, notice how the two graphs have the same information, but the curve looks very different.
When you produce graphics, how the user will react at first glance must be considered. The second graph is designed to give an impression that production has dramatically increases. However, a closer look at the numbers does not actually show that.
The slope of the line matters in how people interpret a graph. You must choose the spacing for each axis so that the slope of the line accurately reflects the actual trend of the data. Both graphs depict the same data, but the slope changes drastically because of the different scales used in designing each set of axes. Most graphics programs allow you to adjust the intervals on the x and the yaxis, but you must understand when and why to do that adjustment; the program defaults are probably giving misleading results.
People do not closely read graphs. They look at the basic curve and go with first impressions. As an ethical writer, you cannot take the attitude that the person must examine the data closely. You must understand how the audience reads and write/design information such that it provides them with accurate information and does not mislead them.
If you are wondering, the defaults in Microsoft Excel are really great at making misleading graphs. It is obvious that the program was set up by programmers that had no real feel for how graphs are used or read.
Some of the ways to create misleading graphs:
Not starting the Y axis scale at zero. By starting at a higher number, you can create a graph that appears to have a different slope than it really has. (this is how the above example created its impression). The above bar charts use this trick.  
Making one of the points really close to the X axis. This also requires you to pick the starting point of the Y axis. By making a data point look very small, it can lead the reader to think it has a very low value. The fact the yaxis starts at a nonzero value is lost.  
Using a very high max value for the Y axis. This makes all the bars or the line seem very short or close to the X axis. The intent is for the reader to think they all have very small values. Putting 2 charts side by side with one with large bars (income) and one with short bars (expenses) can make it look like an organization turned a big profit. Yet, if you look, the two totals are the same. Only the graph scaling makes it look different.  
Using a max value that the Y axis that makes one of the bars almost touch it. This gives the impression that the value has reached as high as it can  
3D charts can create perspective problems. In the 3D version, the redish and blueish areas are almost the same, but the blue appears larger. When more slices of varying sizes are used, this can be even more misleading. The 2D version makes it much easier to see the true relative size of the pieces. 

.
Design by Michael J. Albers Copyright 2017. All rights reserved. 