Numbers, tables, and graphs are very useful when describing a single set of values or showing an association between two sets of values. A single set of values are used in everyday life. For instance, the teaching staff is fond of using single sets of values when evaluating the learners’ academic performance. A lecturer can have a list of all the marks of his or her students for a particular assessment exam they did in class. The list of the exam marks of three students might look like this: (1) 24; (2) 35; (3) 21. The above list describes a single set of values by use of numbers. The same single set of values can as well be described by use of a table as shown below:
For two sets of values, numbers can be used to show an association between two sets of values. Below are two sets of values that were recorded in an experiment.
Like single sets of values, the two sets of values can also be entered in a table or represented through a graph. Two sets of values can be obtained from the correction of two variables with either a negative or positive correlation. Such kinds of values are first of all recorded in a table for easy analysis. Then they are analyzed by use of tools such as SPSS to find the results.