Pictographs

This tutorial is going to teach you about pictographs. You’ll learn about:

1. Pictographs
2. Misleading Pictographs

1. Pictographs

Pictographs are plots that use pictures instead of dots or bends.

Pictograph

A graphical display that uses pictures of physical objects rather than dots or bars to indicate relative size of numbers.

Pictographs show up in newspapers a lot because they're very visually appealing.

Suppose that a class of 17 students is asked their favorite sport. One student might have drawn this graph to illustrate the results.

The three soccer balls meant that three students said that soccer was their favorite sport. The five baseballs means that 5 students said baseball. And the nine basketballs means that nine students said basketball. This is a completely valid graph. It's very analogous to a dot plot, except we're using pictures instead of dots.

Another student might have created this dot plot:

This looks a little funny because there's half of a soccer ball, half of a baseball here, and half of a basketball here. But notice, this student went on to say that every basketball, soccer ball, or baseball actually counts as two students. So one ball, which is two students, and another half a ball, which is half of two more students, makes three students, which is what the other student’s pictograph looks like. This is the same as the data that was presented by the other student.

A pictograph is going to use pictures instead of a scale or dots.

2. Misleading Pictographs

The only problem with pictographs is that sometimes they can be misleading.

In this figure, the USA had the most and Russia had the next most. But it's not really clear what one medal icon actually means in terms of relative size. What we see is that if you divide the 1975 by six medal icons, one metal icon actually counts for 329 medals for the USA, but only 200 medals for Russia.

In fact, none of these are very consistent.

What we should have done is chosen a medal icon to represent a certain number of medals and then just extended the ribbon out that far. A better looking pictograph would be something like this:

Here, the medal icon is 100 medals and the results will be rounded to the nearest 100. So this lines up 20 medals for the USA because the nearest 100 would be 2000. Russia then would have half as many medal icons to represent their 999 medals. This shows much more accurately how many more Olympic medals the USA has then the other countries.

Pictographs will use graphics instead of scales or dots to display differences in a distribution. They are legitimate graphs and they're not used too much outside of newspapers and magazines, because they are so visually appealing, they show up in these a lot. You do need to take care though, to make sure that you're not creating misleading pictographs. You want your pictures to actually represent the same amount in each category. And you don't want to visually distort the picture either.

Thank you and good luck!