This method consists in preparing a questionnaire (a list of questions relating to the field of inquiry and providing space for the answers to be filled by the respondents) which is mailed to the respondents with a request for a quick response within the specified time. A polite covering note, explaining in detail the aims and objectives of collecting the information and also the operational definitions of various terms and concepts used in the questionnaire is attached.
Respondents are also requested to extend their full co-operation by furnishing the correct replies and returning the questionnaire duly filled in time. Respondents are also taken into confidence by assuring them that the information supplied by them in the questionnaire will be kept strictly confidential and secret. In order to ensure a quick and better response, the return postage expenses are usually borne by the investigator by sending a self-addressed stamped envelope. This method is usually used by the research workers, private individuals, non-official agencies, and sometimes even by the government.
In this method, the questionnaire is the only medium of communication between the investigator and the respondents. Consequently, the most important factor for the success of the ‘mailed questionnaire method’, is the skill, efficiency, care, and wisdom with which the questionnaire is framed. The questions asked should be clear, brief, corroborative, non-offending, courteous in tone, unambiguous, and to the point so that not much scope of guessing is left on the part of the respondent. Moreover, while framing the questions the knowledge, understanding, and the general educational level of the respondents should be taken into consideration.
We now list out some of the merits and demerits of the mailed questionnaire method of data collection.
Advantages of Mailed Questionnaire Method:
- Of all the methods of collecting information, the ‘mailed questionnaire method’ is by far the most economical method in terms of time, money, and manpower (labor) provided the respondents supply the information in time.
- This method is used for extensive inquiries covering a very wide area.
- Errors due to the personal biases of the investigators or enumerators are completely eliminated as the information is supplied directly by the person concerned in his own handwriting. The information so obtained is original and much more authentic.
Disadvantages of Mailed Questionnaire Method:
- The most serious drawback of this method is that it can be used effectively with advantage only if the audience is literate and can understand the questions well and reply to them in their own handwriting. Obviously, this method is not practicable if the people are illiterate. Even if they are educated, there may be a number of persons who are not interested in the particular inquiry being conducted and as such, they adopt an attitude of indifference towards the inquiry. In the case of those who return the questionnaires after filling, a number of them supply haphazard, vague, incomplete, and unintelligible information. Thus, this method generally suffers from a high degree (i.e., very large proportion) of non-response and consequently, the results based on the information supplied by a very small proportion of the selected individuals cannot be regarded as reliable.
- Quite often people might suppress correct information and furnish wrong replies. We cannot verify the accuracy and reliability of the information received. In general, this method also suffers from the low degree of reliability of the information supplied by the respondents.
- Another limitation of this method is that at times, informants are not willing to give written information on certain personal questions like income, property, personal habits, and so on.
- Since the questionnaires are filled by the respondents personally, there is no scope for asking supplementary questions for cross-checking the information supplied by them. Moreover, the doubts in the minds of the informants, if any, on certain questions cannot be dispelled.
Business Statistics – SC Gupta and Indra Gupta.