Question

Deceptive Graphs. In Exercises 17–20, identify how the graph is deceptive.

Incomes and Academic Degrees The accompanying graph depicts workers with various academic degrees along with their income levels.

Short answer

The given pictograph incorrectly highlights the increase in the value of income as the difference between the volumes of the largest and smallest cubes appears to be 10 times, whereas the actual difference in the income levels is approximately thrice. Similar is the case with the differences in each successive block.

Therefore, by looking at the given graph, it appears that the income level increases by a large amount when the real increase is comparatively less substantial.

This creates a false image for the readers.

Step-by-step solution

Given information

A pictograph depicts the income levels of workers with different degrees using four blocks.

Describe a deceptive graph

A graph is deceptive in nature when the reader is unable to get a clear or accurate perception of the data. A graph can be inferred as deceptive when compared to the actual data.

Identify the deceptive trait in the graph

The actual incomes along with the academic degrees are:

Degree	Income
No high school diploma	$24,544
High school diploma	$33,852
Bachelor’s degree	$57,616
Advanced degree	$80,877

The graph denotes income levels in the form of 3-D images. Visually, the reader would judge the results by the volume of the cubes.

By observing the graph, the difference in the income levels appears to be huge as the volume of successive blocks increases by a large amount when the actual increase in the income level is small.

For example, the difference in the volumes of the blocks corresponding to the income level of “Advanced degree” and “no High School Diploma” appears to be approximately 10 times. The real increase in the income level of workers with the two types of qualifications is approximately thrice.

Therefore, the given graph inaccurately represents the increase in income level of workers with the different kinds of degrees and leaves a false impression in the minds of the readers.