Distorting the Truth with Descriptive Statistics Flashcards
How can axes be altered to misrepresent stastical findings?
increase the distance between successive units on the vertical axis—that is, stretch the vertical axis by graphing only a few units per inch
What is a good indication of stretching?
A long vertical axis
What is an ethical principle in statistics regarding graphs?
Intentionally distorting a graph to portray a particular viewpoint is considered unethical statistical practice.
How can bars in bar graphs be distorted? What does this do?
making the width of the bars proportional to their height.
The distortion is that the reader may tend to equate the area of the bars with the percentage of deaths occurring at each highway when, in fact, the true relative frequency of fatal accidents is proportional only to the height of the bars.
How can the “average” be distorted?
Unclearly defined; are we speaking about the median or the mean?
What needs to be included in addition to a measure of central tendancy?
A measure of variability.
How can percentages be misleading?
Don’t include the sample size; sometimes reporting the actual number of incidences gives a better picture of the data instead of summarizing with percentages.
