Types of Data: An Introduction There are two types of data i.e. the primary and the secondary sources of data. These are briefly stated below as a brief introduction of the two types:
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Primary Data: Data collected by investigator for his own purpose, for the first time, from beginning to end, are called primary data. These are collected from the source source of origin origin.. In other other words words data data origin originall ally y collec collected ted in the process process of investigation are known as primary data. Primary data are original. The concerned investigator is the first person who collects this information. The primary data is thus first hand information.
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Secondary Secondary Data: Data: Secon Seconda dary ry data data is the the info inform rmat atio ion n whic which h is alre alread ady y in exis existe tence nce,, and and whic which h has has been been colle collect cted ed,, for for some some othe otherr purp purpos osee than than the the answering of the question at hand. In other words data collected by other persons is called secondary data. There data are, therefore, called second hand data. These are available in published or unpublished forms.
Primary Data Primary sources are sources produced by those who were participants, observers, or in other respects close to the events and changes they depict.1 Also the data are original obser observa vati tion onss colle collect cted ed by the the rese resear arche cherr or his his agent agentss for for the the firs firstt time time for for any any investigation and used by them in the statistical analysis analysis..2 Primary data is useful for current as well as future studies. Primary resources are original sources of information on which other research is based, including documents such as poems, diaries, court records, interv interview iews, s, survey surveys, s, and fieldw fieldwork ork.. Prima Primary ry materi materials als also also includ includee resear research ch resul results ts generated by experiments, which are published as journal articles in some fields of study 1
Webster, C.W. John. Studying History. Macmillan India Private Limited. New Delhi. 1997. p. 69. Gupta, Santosh. Research Methodology & Statistical Techniques. Deep & Deep Publications Private Limited. New Delhi. 2005. p. 128.
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and sets of data, such as census statistics which have been tabulated, but not interpreted. interpreted.3 Hence, it should be collected with utmost care.4 The primary data can be collected various methods the most popular being the following methods: •
Observation Method : In the observation method, the investigator will collect data data throug through h person personal al observ observati ations ons.. General Generally ly,, observa observatio tion n method method of data data collection deals with the recording of the behavior of respondents/sampling units. Take the case of consumers transacting with a bank. Here, the behavior of the consumers like, patience while waiting, way of moving with the bank employees, help helpin ing g fell fellow ow consu consume mers rs fill fill up the the form forms, s, etc. etc.,, will will be obse observ rved ed by the the invest investiga igator tor.. The identi identity ty of the invest investiga igator tor should should not be reveal revealed ed to the consumers. If it is known to the consumers, they may change their behavior. This meth method od help helpss capt captur uree the the behav behavio iorr of cons consum umer erss dire direct ctly ly.. Bu, Bu, it is a time time cons consum umin ing g and and cost costly ly exer exerci cise se.. Also Also,, it suff suffer erss from from pers persona onall bias biases es of investigators which will distort the findings.5
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Personal Interview : Under this method, data is collected by the investigator personally by asking questions pertaining to the inquiry from persons from whom the information is to be obtained. Thus, is a person wants to study the spending habits of university students he may contact and interview students personally and collect the desired information. As the investigator is present on the spot for conducting the enquiry, the data collected by him would be first hand and original in character.6 The merits of this method are originality of the data, accuracy of the data, reliability and elasticity of extraction of information from the informant. The demerits being that the method makes it difficult to cover wider areas causing limited coverage, there may be presence of personal bias of the inquirer and the method is expensive.
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Indirect Personal Interview : Indirect personal interview is the method by whic which h info inform rmat atio ion n is obtai obtained ned not not from from the the pers person onss rega regard rdin ing g whom whom the the information is needed. It is collected from the other persons who are expected to
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http://library.uwsp.edu/guide http://library.uwsp.edu/guides/webtutorials/ s/webtutorials/primary.htm primary.htm Panneerselvam, Panneerselvam, R. Research Methodology. Prentice Hall of India Private Limited. New Delhi. 2008. p.18. 5 Panneerselvam, Panneerselvam, R. Research Methodology. Prentice Hall of India Private Limited. New Delhi. 2008. p.18. 6 Gupta, Santosh. Research Methodology & Statistical Techniques. Deep & Deep Publications Private Limited. New Delhi. 2005. p. 135. 4
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possess the necessary information. These persons are known as witness. For example, by this method, the data on the economic conditions of the workers may be collected from their employers rather then the workers themselves. 7 The merits of this method are that it helps in covering a wider area while remaining cheaper and simple simple.. The demeri demerits ts of this this method method being that that the informat information ion is less less accurate, may be biased and may also sometimes lead to doubtful conclusions. •
Telephone Interview : Telephone interview is considered to be a cost effective and dominant data collection method because that travel time of interviews is totally eliminated, the cost of travel of interviews is also eliminated, there is a grater possibility of reaching the consumers all over the area, the total time of conducting conducting the interview interview of the sample is least when compared to other methods and there is a grater possibility of random selection of respondents among the population having a telephone connection. Though it has many advantages the method has certain disadvantages as well like it is impossible to use visual aids, it implies exclusion of population who are not having a telephone connection and the interviewee may discontinue conversation in the midway. midway.8
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Mail Mail Survey Survey// Mailed Mailed Questi Questionn onnair airee : Unde Underr the the mail mailin ing g meth method od the the ques questi tion onna nair ires es are are mail mailed ed to the the info inform rman ants ts.. A lett letter er is atta attach ched ed with with the the questionnaire giving the purpose of enquiry. It is also assured that the information would be kept a secret. The informant notes the answers against the questions and returns the completed questionnaire to the investigator 9. The main advantages of this method being that this method is economical and helps cover a wider area. The demerits being that there may be lack of interest on the part of the informant, there is less flexibility as the informant might not understand what the question demands exactly, the results are less accurate and subject to bias of the informant.
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Questionnaires In-charge of Enumerators : Enumerators are those persons who who help help the the inve invest stig igat ator orss in coll collec ecti ting ng the the data data.. Unde Underr this this meth method od,, a questionnaire is prepared according to the purpose of enquiry. The enumerator
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Jain, T.R. & Ohri V.K. Statistics for Economics and Indian Economic Development. V.K. Publications. Publications. New Delhi. 2009. p.26. 8 Panneerselvam, Panneerselvam, R. Research Methodology. Prentice Hall of India Private Limited. New Delhi. 2008. p.20. 9 Jain, T.R. & Ohri V.K. Statistics for Economics and Indian Economic Development. V.K. Publications. Publications. New Delhi. 2009. p.29.
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himself himself approaches approaches the informant informant with the questionnair questionnaire. e. The questionnai questionnaires res which are filled by the enumerator themselves by putting questions are called schedules. Thus, under this method, the enumerator himself fills the questionnaire after seeking the information from the informants. The enumerators are given training training to fill the schedules and put the question question intelligently intelligently to obtain obtain accurate accurate information10. The merits of this method being that it helps in covering a wider area with accuracy and completeness. While its shortcomings being that this meth method od is expe expens nsiv ive, e, time time cons consum umin ing g and and may may be subj subjec ectt to untr untrai aine ned d enumerators or those who may be partial.
Secondary Data Secondary data is data collected by someone other than the user. Common sources of secondary data for social science include censuses, surveys, and organizational records11. Secondary data analysis saves time that would otherwise be spent collecting data and, particularly in the case of quantitative data, provides larger and higher-quality databases than would be unfeasible for any individual researcher to collect on their own. In addition to that, analysts of social and economic change consider secondary data essential, since it is impossible to conduct a new survey that can adequately capture past change and/or developments.12 Secondary sources are based on primary sources and produce secondhand or someti sometimes mes even thirdthird-han hand d evidenc evidence. e.13 In other other words, words, second secondary ary data are collected by others and used by others.14 Secondary resources describe or analyze the primary sources.15 This type of data is mainly derived from books, publications, foreign government publications, international bodies’ publications, technical or trade reports, association reports, public reports, etc. 10
Jain, T.R. & Ohri V.K. Statistics for Economics and Indian Economic Development. V.K. Publications. New Delhi. 2009. p.30. 11 http://en.wikipedia.org/wik http://en.wikipedia.org/wiki/Secondary_da i/Secondary_data ta 12 http://en.wikipedia.org/wik http://en.wikipedia.org/wiki/Secondary_da i/Secondary_data ta 13 Webster, C.W. John. Studying History. Macmillan India Private Limited. New Delhi. 1997. 14 Gupta, Santosh. Research Methodology & Statistical Techniques. Deep & Deep Publications Private Limited. New Delhi. 2005. 15 http://library.uwsp.edu/gu http://library.uwsp.edu/guides/webtutoria ides/webtutorials/primary.h ls/primary.htm tm
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The chief sources of secondary data can be classified according to 2 methods. The first method differentiates according to whether the source is published or unpublished.16 While the second basis differentiates on the grounds of internal and external sources.17
According to the first mode of differentiation the sources are divided as under: •
Published Published Sources Sources : Ther Theree are are a number number of nati nation onal al orga organi nizat zatio ions ns and and international agencies which collect data relating to the various spheres like business, labor, production, etc., to name a few. This data is periodically published and serve as a very important source of secondary data. The various sources are listed below: o
Official Publications of Central Government
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Publications of Semi-Government Statistical Organizations
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Publications of Research Institutions
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Publications of Commercial and Financial Institutions
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Reports of Various Committees and Commissions Appointed by the Government
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Newspapers and Periodicals International Publications
Unpublished Sources : These sources include things like personal diaries, letters, memoirs, biographies, etc.
As per the second method do division sources are of the following types: •
Intern Internal al Source Sourcess: Inte Intern rnal al sour source cess of seco second ndar ary y data data for for mark market etin ing g applications are as follows: o
Sales records
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Market activity
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Cost information
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Gupta, Santosh. Research Methodology & Statistical Techniques. Deep & Deep Publications Private Limited. New Delhi. 2005. 17 Panneerselvam, Panneerselvam, R. Research Methodology. Prentice Hall of India Private Limited. New Delhi. 2008.
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Distributor reports and feedback
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Consumer feedback
External External Sources Sources: Vario Various us exte extern rnal al sour source cess of data data are are gover governm nment ent publ public icat atio ions ns,, gove govern rnme ment nt publi publica cati tions ons,, jour journa nals ls,, publi publica cati tions ons of trade trade associations, books, magazines, newspapers, annual reports, etc. This form even includes publications from the UN, WHO, ILO, etc.
Principal Differences between Primary & Secondary Data “The distinction between primary and secondary data is one of the degree. Data which are primary in the hands of one party may be secondary in the hands of the other.” -Secrist18
The following are some principal differences between primary and secondary data:
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Difference in Originality : Primary data are original because they are collected by the investigator from the source of their origin. Against this, secondary data are already in existence and, therefore, are not original.19
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Difference in the Suitability of Objectives : Primary data are always related to a specific objective of the investigator. These data, therefore, do not need any adjust adjustmen mentt for the concer concerned ned study. study. On the other other hand, hand, seconda secondary ry data data have already been collected for some other purpose. Therefore, these data need to be adjusted to suit the objective on the study in hand. hand.20
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Difference in Cost of Collection : Primary data are costlier in terms of time, money and efforts involved than the secondary data. This is because primary data are collected for the first time from their source of origin. Secondary data are
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Jain, T.R. & Ohri V.K. Statistics for Economics and Indian Economic Development. V.K. Publications. New Delhi. 2009. p.24. 19 Jain, T.R. & Ohri V.K. Statistics for Economics and Indian Economic Development. V.K. Publications. New Delhi. 2009. p.23. 20 Ibid.
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simple collected from the published or unpublished reports. Accordingly, they are much less expensive.21
Choice between Primary and Secondary Data The choice between primary and secondary sources of data mainly depends upon the nature, objectives and scope of inquiry availability of time and money, degree of accuracy desired and the status of the investigator. The primary data are more reliable on the face, but the secondary data can be relied only be examining the source from which they they have have been been obtai obtained ned,, thei theirr true true signi signifi fica canc nce, e, inco incomp mple lete tenes nesss and meth method od of collection. Sometimes in a certain investigation both primary and secondary data are used as supplement to each other, it may be pointed out that today in a large number of statistical inquiries secondary data are generally used because fairly reliable published data on a large number of diverse fields are now available. In face, primary data are collected only if there do not exist any secondary data suited to the investigation under study. The points discussed as under are noteworthy for the preference of primary source in comparison to the secondary source22:
The primary source gives data in grater details compared to secondary source. The Secondary source often omits part of the information.
In the the seco seconda ndary ry sour source ce,, ther theree is a poss possib ibil ilit ity y of mist mistake akess due to erro errors rs in transcription made then the figures were copied from primary source.
The primary source includes definitions of terms and units used. It is essential that the investigations understand the meaning of units in which data are recorded.
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Jain, T.R. & Ohri V.K. Statistics for Economics and Indian Economic Development. V.K. Publications. New Delhi. 2009. p.24. 22 Gupta, Santosh. Research Methodology & Statistical Techniques. Deep & Deep Publications Private Limited. New Delhi. 2005. p. 129
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The primary source also includes a copy of the schedule used in data collection together together with the prescription prescription of the procedure procedure used in selecting selecting the sample and the size of the sample.
The availability of time at the disposal of investigations also affects the choice of method to be adopted in the collection of data. If the data is needed immediately then secondary sources are taken. On the other hand, if time is sufficient, it is recommended to use primar primary y method method of data data collec collectio tion n becaus becausee primar primary y data data are more more accurat accuratee and reliable compared to secondary data.
The availabi availabilit lity y of finance finance also influe influence ncess the method method to be adopte adopted d in the collec collectio tion n of data. data. If the data data collec collecti ting ng author authorit ity y has vast vast financ financial ial resour resources ces at its its disposal, it is better to adopt primary method. On the contrary, if the data collecting agency has less financial resources, secondary data should be adopted even though the secondary data is are not as reliable as primary data.
The availability of trained investigators also affects the choice of the method to be employed in data collection. If trained investigators are available, primary method should adopted for the collection of data. In case of non-availability of trained investigators, it is recommended to adopt secondary method of data collection.
The objective and the scope of the enquiry also determine the method to be adopted in the collection of data. The selected method must suit the objective and the scope of the inquiry.
Problems to be kept in Mind While Using Data
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While using either of primary or secondary data problems to be kept in mind to avoid future difficulties are as under:
The Problem of Genuineness Main aim is to get evidence and this has to be the closest to the truth i.e. objective to problem of genuineness arises. For example if a source entitled ‘The Presidential Address of Jawaharlal Nehru delivered at the Indian National Congress at Lahore, December 29, 1929’ is in fact an exact copy of Nehru’s own Presidential remarks on that occasion then the source is genuine.23 The second possibility is that the source is a forgery, or partly forged or written by an anonymous writer for Nehru.
The Problem of Reliability A document may be one hundred percent genuine and still contain large quantities of misinformation. One should therefore cross-examine each source in order to determine the degree of reliability reliability or trustwort trustworthines hinesss of the evidence evidence contained contained in it.24 One should consider various questions while checking the reliability of the like what was the position of the facts in consideration? Is the examiner a trustworthy person? What are the sources used to collect the data? Was a proper method used to collect the data? Was the time of data collection appropriate to the study?
The Problem of Suitability of Data The kind of data that may be useful to one study might not be suitable for the other study. One has to scrutinize the data to ascertain its suitability in the study being conducted. It is necessary to keep in mind the object, scope and nature of the inquiry being made.
The Problem of Adequacy of Data The data being used to construct the inquiry must also be adequate for the study being made. For example data is considered inadequate if it’s related to a narrower area or a 23 24
Webster, C.W. John. Studying History. Macmillan India Private Limited. New Delhi. 1997. p. 73. Webster, C.W. John. Studying History. Macmillan India Private Limited. New Delhi. 1997. p. 77.
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wider area than the area under question. It is found that the data are suitable for the purpose of the investigation; they should be tested for adequacy. Adequacy of the data is to be judged in the light of the requirements of the survey and the geographical area covered by the available data.
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Bibliography
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Gupta, Santosh. Research Methodology & Statistical Techniques. Deep & Deep Publications Private Limited. New Delhi. 2005.
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Kothari, C.N. Research Methodology: Methods & Techniques. New Age International Publishers. New Delhi. 2008.
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Panneerselvam, R. Research Methodology. Prentice Hall of India Private Limited. New Delhi. 2008.
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Webster, C.B. John. Studying History. Macmillan India Private Limited. New Delhi. 1997.
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Jain, T.R. & Ohri, V.K. Statistics for Economics and Indian Economic Development. V.K. Publications. 8th Edition. New Delhi. 2009.
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Webography
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http://library.uwsp.edu/guides/webtutorials/primary.htm
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http://www.collectionscanada.gc.ca/education/008-3010-e.html
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http://library.ucsc.edu/help/howto/distinguish-between-primary-and-secondarysources
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http://www.collectionscanada.gc.ca/education/008-3010-e.html
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http://www.wwnorton.com/college/history/ralph/research/prisec.htm#primary
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http://www.lib.berkeley.edu/TeachingLib/Guides/PrimarySources.html
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http://en.wikipedia.org/
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