In any statistical investigation, the collection of the numerical data is the first and the most important matter to be attended. Often a person investigating, will have to collect the data from the actual field of inquiry. For this he may issue suitable questionnaires to get necessary information or he may take actual interviews; personal interviews are more effective than questionnaires, which may not evoke an adequate response. Another method of collecting data may be available in publications of Government bodies or other public or private organizations.

Sometimes the data may be available in publications of Government bodies or other public or private organizations. Such data, however, is often so numerous that one’s mind can hardly comprehend its significance in the form that it is shown. Therefore it becomes, very necessary to tabulate and summarize the data to an easily manageable form. In doing so we may overlook its details. But this is not a serious loss because Statistics is not interested in an individual but in the properties of aggregates. For a layman, presentation of the raw data in the form of tables or diagrams is always more effective.

Index

2.1 Introduction
2.2 Tabulation
2.3 Classification
2.4 Methods of classification
2.5 Relative frequency distribution
2.6 Cumulative frequency
2.7 Bivariate frequency distribution

Chapter 3