Statistics: Graphs and Pictograms

Date: 6/6/96 at 10:54:10
From: Anonymous
Subject: Statistics: Graphs

In statistics, what makes a graph a pictogram?

I have tried looking up the index of some books on the Internet, a 
dictionary, and also searching for "pictogram" on NetSearch. I also 
looked around this site - including the On-Line Mathematics 
Dictionary, but they aren't very clear.

A particular problem is a graph in one book where some planes are set 
out like a bar graph. The planes are shown one after another with 
their tails at the left hand axis. The longer (and larger) planes are 
for the companies with the most deliveries.

There are two views. One says that they are just a wierd kind of bar 
graph and not a pictogram. They other says that they are pictograms, 
but they are bad statistics. (They are poor because the data are 
represented by the LENGTH of the plane, but the AREAS of the larger 
planes convey an impression that they are much larger.)

Date: 6/30/96 at 15:57:23
From: Doctor Robert
Subject: Re: Statistics: Graphs

I suppose that there are many ways to define a pictogram, but in its 
simplest form it means a type of bar graph where the NUMBER of images 
indicates the length of the bar.  Usually, there should be some type 
of key so that one can get numerical data from the pictogram.  

Personally I think that a standard bar graph will convey the data with 
more clarity, less confusion. I agree with you that if the length of a 
plane represents a number, that would be confusing.  I would rather 
see each plane represent a certain number of deliveries rather than 
the length of the plane represent a certain number of deliveries.

Good luck!

-Doctor Robert,  The Math Forum
 Check out our web site!  http://mathforum.org/dr.math/