Univariate, bivariate and multivariate are the various types of data that are based on the number of variables. Variables mean the number of objects that are under consideration as a sample in an experiment. Usually there are three types of data sets. These are;
Univariate data is used for the simplest form of analysis. It is the type of data in which analysis are made only based on one variable. For example, there are sixty students in class VII. If the variable marks obtained in math were the subject, then in that case analysis will be based on the number of subjects fall into defined categories of marks.
Bivariate data is used for little complex analysis than as compared with univariate data. Bivariate data is the data in which analysis are based on two variables per observation simultaneously.
Multivariate data is the data in which analysis are based on more than two variables per observation. Usually multivariate data is used for explanatory purposes.