Descriptive statistics in
Other graphical representations
In the last chapter, we looked at how we can use numbers to describe our results. But numbers always need to be interpreted, no matter how clearly they are presented. Even tables of results require us to read through the numbers, and to work out what they mean. Sometimes it is much quicker to convert the information into a picture instead. Graphical representations do much the same job when we are trying to understand numerical data as metaphors do when we are trying to understand complex verbal ideas. By converting the information into an image - either a verbal image or a picture – we are able to make comparisons with things we already know, and so grasp important features of the information more quickly.
What do these threeterms mean?graphical representationscontinuous variabledescriptive statistics
There are a number of different forms of graphical representation; and, as with measures of central tendency and dispersion, which one we choose depends entirely on what kind of information we have and what we want to use it for. Sometimes we are looking at how a single measure varies or fluctuates over time, or in response to a single changing variable, and for that we would use a graph. Sometimes our data are arranged in categories, and what we want is an image which will tell us, quickly, how many scores we have in each category. For that, we would use some kind of bar chart. Sometimes we are interested in proportions, or shares, and we want to use a graphical representation which will tell us what sort of share of the whole is formed by each type of score; we would use a pie chart to look at these. And there are other types of graphical representation, too, which psychological researchers use in their research reports, and which we will look at in this chapter.