Statistics: Meaning and Scope (Need for Statistical data - (Statistical…
Statistics: Meaning and Scope
Need for Statistical data
- (Statistical data is needed for)
Needed to approve or disapprove an economic theory
Needed to reveal the structure of an economy
Needed for planning
Needed to access the success of programmes and policies of the government
Scope of Statistics
The word statistics is used in two senses: a) the plural sense b)the singular sense
The plural sense: Refers to quantitative information or simply statistical data
Singular sense: Refers to method or methods used in arriving at the quantitative information or dealing with it.
Example: Population of India was estimated through census method; that the figures are presented in the tabular form; that population is continuously rising and that it is rising on account of fall in death rate, we are referring to the methods of collection, presentation, interpretation of trend in data and analysis of data respectively. All these steps are statistical methods.
Statistical Data (Plural sense)
Meaning: Numerical statements of facts are statistical data.
Statistical data are aggregates of facts
Single and isolated quantitative figure is not statistics. The group of figures become statistics, which can be compared, analysed, and draw some conclusions from these figures.
Example: 4 students scored 45,60,72,59. Highest marks obtained = 72; Lowest marks = 45; Marks range between 45 and 72. Average marks obtained is 59 = (45+59+60+72)/4 [figures are compared, analysed, and drawn some conclusions)
Statistical data are numerically expressed
Data must be collected in a systematic manner
Figures must be accurate to a reasonable degree or standard
Statistics are collected for a predetermined purpose
Statistical Methods (Singular sense)
Meaning: Statistics is a science of collection, presentation, analysis and interpretation of numerical data.
Collection of data
Data which is collected by the investigator himself is called primary data
Data which is collected from other sources is called secondary data
Presentation of data
Data collected to be arranged in a systematic manner and present the data in the forms such as frequency distribution in the form of tables, graphs, diagrams and pictures
Analysis of data
Analysis is done using the statistical tools such as measures of central tendency like mean, median, mode
Interpretation of data
It is the last stage of statistical enquiry