Meaning of Census Investigation : When for a particular problem important statistical details are collected from each unit of the related data, then it is called census investigation.
For example : If in any educational institution the data regarding the monthly income of 500 students is collected, then it is called census investigation. In India population census is an example of cencus investigation.
Uses of Census Investigation :
This method of investigation is useful in the following cases:
1. When detailed study of each unit is necessary.
2. High level of accuracy is necessary.
3. Area of investigation is limited.
4. Investigator has sufficient sources of finance.
Merits :
- High level of accuracy : Data collected through this method is reliable and accurate. For this reason the investigation done through this method has high level of accuracy.
- More reliablity : In this method, information is collected from each unit of the data, therefore the available data is more reliable.
- Detailed information : In this method because each unit of data is contacted, therefore it becomes possible to collect more and more information.
- For example : In population census, only census information relating to number of males and females in the country is not collected, but the information related to their financial position, health situation, qualification, marital status, etc. is also collected.
- Used when diversity exists among the units : This method is suitable where diversity exists between the units of data and where the use of sampling method is not possible.
Demerits :
- More expensive : This method consumes more time, money and labour. The results of investigation done by this method are received after a long delay, therefore, this method is mainly used by the government.
- Lack of trained enumerators : If the enumerators are not properly trained, then the results obtained are not satisfactory.
- Not possible in some situations : When the area of investigation is large and it is not possible to collect information from each unit of the population, then the use of this method is not possible.
