Give a brief account of the chief methods of collecting primary data and bring out their merits and defects.
Give a brief account of the chief methods of collecting primary data and bring out their merits and defects.
Or
Explain the various methods of collecting primary data and point out their relative merits and demerits.
Ans.
Collection of Primary Data
Primary data may be collected by means of the following methods, which are called Primary Methods:
1. Direct Personal Investigation.
2. Indirect Oral Investigation.
3. Information Through Correspondents.
4. Information Through Schedules to be filled in by Informants.
5. Information Through Schedules in charge of Enumerators.
1. Direct Personal Investigation: This method consists in the collection of data personally by the investigator from the field of inquiry by holding personal interview directly with the responded or the people who are the units of inquiry. Such investigation is suitable where the field of investigation is not wide, and is local, confined to a single locality and where originality, secrecy and correctness of collected data is vital. Family income-expenditure in limited area, economic conditions of workers, literate unemployment are some examples where this method of inquiry may be deployed. In European countries Leplay employed this method of investigation in the collection of statistics regarding income and expenditure of the workers and Arther Young for the study of agricultural production. If the investigator exercises resistence, politeness, unbiasness, and far sightedness, reliable data are obtained by this method. He must be well versed with the language, customs and living standards of respondents.
Merits: The following are the merits of this method:
(i) Accuracy: The first hand information is obtained by the investigator himself, who is present in the area of investigation, hence it is more reliable and accurate.
(ii) Additional Information Available : Some additional reliable information may be gathered under this method without incurring extra cost and wasting extra time.
(iii) Homogeinety : Since the data are collected by one person, there is uniformity in collection of data, as such collected data are homogeneous in character.
(iv) Flexibility: The method is quite flexible since the investigator may modify the questions slightly in order to collect the required information.
Demerits: The following are its demerits:
(i) Limited Area : This method is not suitable if the field of investigation is too wide in terms of the area to be covered and number of informants.
(ii) Prejudice or Bias: The personal biasness and whim of the investigator may affect the findings of the investigation in some cases.
(iii) Wasteful: This method causes waste of time, money and manpower.
(iv) Unreliable Results: Since the area of investigation is not wide, the data collected may not represent the universe. Hence the results obtained may be wrong and unreliable.
2. Indirect Oral Investigation
Under this method, interviews are held, not with the persons directly who are the units of inquiry but with other related persons or witnesses who possess information pertaining to those units. For example, information regarding living conditions or workers may not be obtained directly from the workers but through mill-owners or trade unions on the basis of oral examination. This method is used when the area of investigation is very wide or it is not possible to contact the informants personally or the units of inquiry are illetrate and do not possess interest to furnish required information. This method of gathering data is usually adopted by enquiry commissions or committees formed by the government.
Merits: The merits of this method are as follows:
(1) Economical : This method saves time, money and manpower and better results are obtained by restricted means.
(ii) Opinion of Experts: Experts opinion regarding inquiry is obtained under this method. Persons, for and against the inquiry are interrogated so as to interpret and discuss different aspects of the problem..
(iii) Unbiasness: Prejudices of the persons when approached directly are avoided with the assistance of third party informants.
(iv) Wide Area: This method is suitable in such inquiries where the area to be covered is very wide and the direct contacts with the informants is neither necessary nor possible.
Demerits: Following are its demerits :
(i) Indirect Information : Under this method, the investigator obtains information indirectly because he does not come in direct contact with informants, the data gathered are not very reliable.
(ii) Evils of witnesses: A wrong and improper choice of witnesses from the data are to be collected may give wrong and biassed information, resulting in fallacious conclusions.
3. Information through local sources or correspondents
Under this method, appointment of local agents or correspondents is made by the investigator in different parts of the field of inquiry, who furnish information from time to time on the basis of their experience. There is always possibility of some errors in personal estimates of correspondents but the errors are compensated in their collective estimates. This technique of data collection is usually employed by newspaper and periodical agencies. Government also use this method for gathering of information about the prices of wholesale price index numbers, and for crop estimates. This method is suitable where accuracy is hardly needed and only estimates and trend are to be ascertained.
Merits: The merits of this method of data collection are:
(1) Economy: This method saves time, money and labour. Information is gathered quickly and without high expenditure.
(ii) Wide Area: This method is suitable where the area of investigation is wide and places are situated at wide distances.
Demerits: The following are its demerits:
(i) Lack of Originality and Accuracy: The data collected under this method lack originality and accuracy since local correspondents furnish information on the basis of estimates.
(ii) Lack of Uniformity: The data collected by different correspondents are different with different definitions, thus it lacks uniformity and homogenity.
(iii) Bias or Prejudice: The data collected are subject to, personal bias of local agents or correspondents.
4. Information through schedules to be filled in by informants
Under this method, the investigator prepares a list of questions (called questionnaire) connected with the inquiry and sends this questionnaire to the informants by post. Duly filled in questionnaire is to be returned back by the informants to the investigator. A letter of request is also appended with the questionnaire in which the object of inquiry along with the request to the informant to fill in and return the questionnaire in time is made. He also assures them to keep the information furnished by them as secret.
While preparing a schedule it must be kept in mind that the questions must be easy, clear and small, less in number. The questions should relate to the inquiry and answerable in yes or no. Such questions should not be included which are ambiguous, non-polite which may aggregate the informants. This method of inquiry can be successful if aforesaid precautions are taken into consideration.
This method of gathering data is suitable where the area is wide, informants are literate. Mostly the opinion surveys, consumer aptitude surveys etc. are done by means of this method. Government also adopts this method for annual survey of industries.
Merits: Following are the merits of this method:
(i) Economy: Under this method information pertaining to wide area can be gathered during less time at less cost.
(ii) Originality: The information is furnished by the informants personally, as such, the data are original in character.
(iii) Wide Area : This method is suitable where area of investigation is wide enough.
Demerits: This method suffers from many demerits which are as under:
(i) Incomplete and Ambiguous Information: Since informants hardly take any interest in filling the questionnaire, which may either be not returned by them, or may not return in time, or even if some of them return, may be inaccurately or improperly filled in because some questions may not be properly understood by them, while some may not answer because of their indifference or suspicion. As such most of the persons do not give response and some are biased in giving answers. Thus, the information gathered is inaccurate and incomplete.
(ii) Lack of Accuracy: Data gathered by this method are not accurate because of many reasons. If a schedule is not prepared with caution, the answers to many questions may be wrong, ambiguous and biased. As such, wrong data are collected.
(iii) Lack of Flexibility: This method is not flexible since in case of incomplete answers it is difficult to obtain supplementary answers.
(iv) Limited Scope: This method can be used effectively only where the informants are literate. Data cannot be gathered from illiterate informants.
Despite these defects, this method of inquiry is useful where area of investigation is wide, informants are literate so that information may be quickly. For the success of this method schedule should be prepared with caution and efforts be made to receive cooperation and confidence from the informants.
5. Information Through Schedules In charge of Enumerators
The method of Information through schedules to be filled in by the informants has many defects and limitations. Gathered data are also incomplete, inadequate and inaccurate. As such, this method is applied to get rid these difficulties. According to this method, a team of enumerators is selected, who reaches to the respondents personally with the schedule of questions, ask them the questions visiting the informants and record their replies. Specific instructions and necessary training are given to them regarding the information to be extracted from the respondents. The enumerators explain clearly the object of survey, the definitions of basic concepts and rules to the respondents and record their response themselves. The selected enumerators should be wise, skillful, honest, intelligent and diplomat and are well-versed in the local language, customs and traditions of that area. They should be imparted proper training so that the schedules are recorded correctly by them. The work of these enumerators must also be supervised from time to time and guidance should be provided whenever needed. This method is suitable for a very wide area of investigation. It is usually adopted by the government because of very expensive nature. In census of population in India, this method is followed.
Merits: The following are the merits of this method:
(i) Wide Coverage: This method is suitable to gather information where the area of inquiry is very wide and large.
(ii) Accuracy: The information collected under this method is more accurate and more reliable since it is recorded by trained enumerators who can clarify difficult propositions.
(iii) Personal contact : Since enumerators have personal contacts with the respondents, as such correct answers of even complex questions are obtained.
(iv) Unbiasedness: Data are gathered through wise, clever and trained enumerators, as such fear of personal prejudices is minimised.
Demerits: Following are demerits of this method :
(i) Expensive: This method is the costliest of all for collecting primary data.
(ii) Other Difficulties: This method need proper organisation, rather big organisation for imparting training to enumerators and collecting data.
Difference between schedules to be despatched by Mail and Schedules to be Filled in by Enumerators:
These methods are based on schedules and questionnaires and are suitable for wide area of operation. The main difference between these two methods is that under the former, schedules are required to be filled in by the respondents, whereas in the later, enumerators approach personally to the informants to fill in the schedules by asking questions. The former method is suitable for literate informants, and is economical, whereas the later is quite expensive and suitable for illetrate informants.
