Test: Presentation of Data - 1 - Mechanical Engineering MCQ

Statistical data can be presented in three forms namely, tabular presentation, diagrammatic presentation and graphic presentation.

Line frequency graph is obtained from the frequency distribution of discrete variables. Length of the line represents the frequency of that variable.

Width and number of the bar are immaterial in case of bar diagrams. Bar diagram shows statistical data in terms of length of the bar.

When classification is done on the basis of time, the classification is known as temporal classification. Time may be in hours, days, weeks, months, years etc.

The objective of presentation of data is to present classified data visually, thus highlighting basic facts and relationships.

Bar diagram comprises a group of equispaced and equiwidth rectangular bars for each class or category of data. Only one variable can be represented by the simple bar diagrams.

There are three methods of presentation of data. 
(1) Tabular Presentation
(2)Textual or Descriptive presentation
(3) Diagrammatic Presentation

Subdivided or component bar diagrams are used when various components of a variable are to be represented. In these diagrams we cannot only present the different values graphically but can also compare parts of one with another.

When on the basis  presence and absence of an attribute, the data are classified into two classes, one possessing that attribute and the other not possessing that attribute, it is called two-fold classification.

Sub-divided bar diagrams presented graphically on percentage basis gives percentage bar diagrams. These diagrams are used to highlight the relative importance of the various component parts to the whole.