What is difference in popsi & preceis?

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Kuchh naya poochho yaaar



POPSI (Postulate-Based Permuted Subject Indexing)

          The inherent weakness of chain indexing has been its dependence on a scheme of classification. Another weakness was its disappearing chain. In view of this situation, the information scientists at the Documentation Research and Training Centre (DRTC), Banglore, directed themselves from these limitations. the Postulate Based Permuted Subject Indexing (POPSI) is the results of these efforts. It was developed by Ganesh Bhattacharya.

          POPSI does not depend on the Class Number but is based on Ranganathan’s postulates and principles of general theory of classification.

POPSI  is specifically based on:

(a)              a set of postulated Elementary  Categories (ECs) of the elements fit to form component of subject proposition.

Elementary Categories are:

Discipline (D)      - It covers conventional field of study, e.g. Chemistry, Physics, etc.,

Entity (E)    - e.g. Plant, Lens, Eye, Book, etc.,

Action (A)   - e.g. Treatment, Migration, etc; and

Property (P)         - It includes ideas denoting the concept of ‘attribute’ – qualitative or quantitative. e.g. Power, Capacity, Property, etc.

(b)     a set of rules of syntax with reference to ECs

The Syntax is based on the Ranganathan’s general theory of classification.

(c)               a set of indicator digits or notations to denote the ECs and their subdivisions.

          It is got by POPSI table.

(d)  a vocabulary control device designated as ‘classaurus’.


          If A,B,C,D  are subject headings (using  each of the sought terms) then it will generate the following subject entries.













          The above format is exactly like KWOC  index, in which the user is required to read the entire chain every time to get the correct context.

   Steps in POPSI

          The index entries according to this system are generated in a systematic manner with the help of following steps of operation.

1.                Analysis

2.                Formalisation

3.                Modulation

4.                Standardisation

5.                Preparation of EOC

6.                Decision about TA

7.                Preparation of EAC

8.                Alphabetisation

Let us examine these stages with the help of a sample title, ‘Chemical treatment of tuberculosis of lungs’.

1.                Analysis

          Subject indicative expression, the starting point of index generation, may be the title of a paper, a book or any other document. According to the first stage of operation, the expression is analysed to identify the facets in terms of concepts and modifiers. Analysis of the above mentioned example will lead to the following:

D       -        Medicine

E       -        Lungs

A       -        Chemical Treatment

P       -        Tuberculosis

2.     Formalisation

          In the stage of formalisation the sequence of components derived by analysis has to be decided. It involves the arrangement of component terms according to the principles of sequence of components indicating the status of each component term. Applying this principle, the components are sequenced in the following manner to obtain the basic chain:

Medicine (D), Lungs (E), Tuberculosis (P of E), Chemical treatment (A on P)

3.     Modulation

          Each of the component terms in the analysed and formalised subject headings is added some terms (if necessary) to make their understanding more clear. The above chain after modulation will be:

Medicine (D), Man. Respiratory System. Lungs (E), Disease. Tuberculosis (P of E), Chemical treatment (A on P)

4.  Standardisation

          It is concerned with semantics. It helps in the decision of standard terms for synonyms and the terms for reference generation. It is done vocabulary control. In step 3 and 4, classaurus has been suggested to be used. The above chain after this step will be:

Medicine (D), Man. Respiratory System. Lungs (E), Disease. Tuberculosis (P of E), Chemotherapy (=Chemical treatment) (A on P)

5.                Preparation of the EOC(Entry for Organising Classification)

          It consists of preparing the entry for generating organising classification by inserting appropriate notations from the POPSI table. The above chain after this step will take the following shape.

7Medicine, 6 Man. Respiratory System. Lungs, 6.2 Disease. Tuberculosis, 6.2.1 Chemotherapy (=Chemical treatment)

6.  Decision about TA (terms of approach)

          This step is concerned with the decision regarding terms of approach for generating successive index entries and references.

          In this step ‘Lungs’, ‘Tuberculosis’ and ‘Chemotherapy’ are selected as terms of approach and a cross reference entry is decided to be made for ‘Chemotherapy’.

7. Preparation of EAC (Entries for Associative Classification)

          This step consists of preparation of entries under each approach terms and references. This step will result in the following entries.


          7 Medicine, 6 Man. Respiratory  System. Lungs,

          6.2 Disease. Tuberculosis, 6.2.1 Chemotherapy



          7 Medicine, 6 Man. Respiratory  System. Lungs,

          6.2 Disease. Tuberculosis, 6.2.1 Chemotherapy



          7 Medicine, 6 Man. Respiratory  System. Lungs,

          6.2 Disease. Tuberculosis, 6.2.1 Chemotherapy


Chemical treatment

          See Chemotherapy


8.   Alphabetization

          In this step all the index entries including references are arranged in a word by word sequence

(i)     Chemical treatment

                   See Chemotherapy

(ii) Chemotherapy

                   7 Medicine…       …

(iv)            Lungs

          7 Medicine  …       …

(iv)  Tuberculosis

                   7 Medicine  …       …


          POPSI is certainly an extension of Chain Indexing,  though they differ from each other. POPSI has successfully solved the problem of disappearing chain which was a major criticism against chain indexing. POPSI made the indexing system free from classification scheme because this system  is based on general theory of classification and is not tagged with any classification scheme.

   PRECIS (Preserved Context Indexing System)

         Preserved  Context Indexing System (PRECIS)  was developed by Derek Austin in 1968 as a result of long research which the Classification Research Group (CRG) undertook to give a new general classification for information control. This system is considered as the most important development in alphabetical approach to subject specification in recent years.

          The system aims at providing an alphabetical subject index which is able to cater to the variant approaches of the users along with their context. In order to achieve this objective, the system arranges the components of a document,  into a significant sequence, thus, all the important components in the string are used as approach points. Simultaneously, the terms are displayed in such a fashion that every term is related to the next term in a context dependent way. Moreover, the system is amenable to computer operation, which further adds to the advantage of the system as the entries will be prepared and arranged automatically by the computer.

5.4.1.  Essential Features of PRECIS

          PRECIS  has the following important features:-

1.                The system derives headings that are co-extensive with the subject at all access points.

2.                It is not bound to any classification scheme .

3.                The terms are context dependent in nature, which enables the users to identify the entries correctly.

4.                The entries are generated automatically by the computer references between semantically related terms.

5.                It also provides adequate arrangement of references between semantically related terms.

6.                It is a flexible system, as it is able to incorporate newly emerging terms accordingly.

7.                It has introduced the PRECIS  table which puts forth a set pattern for the preparation of entries, thus bringing about  consistency in work.

   Concept of PRECIS

The concept of PRECIS deals with terms, strings, and role  operators

Term: A term is a verbal representation of a concept. It may consist of one or more words.

String:       An ordered sequence of component terms, excluding articles connectives, prepositions, etc., proceded by role operators is called a string. The string represents the subject of the document.

Role Operators: The Operators are the code  symbols which show the function of the component term and fix its position in the strings. These role operators are meant  for the guidance of the indexers only and do not appear in the index entry.

(a)      Preparation of String

          The main or the most important activity in PRECIS indexing is the formation of the string. The preparation of string constitutes the following points:

(i)                 Context dependence

(ii)              One-to-one relationship

(iii)            Provision of role operators

          The component terms are arranged in such a way that they are context dependant, at the same time they are interrelated to each other.

5.4.3   Format of Entry

          There are three formats of making index entries through PRECIS

1.                Standard format

2.                predicate transformation format

3.                Inverted format

1.  Standard Format

        In order to achieve the goal of context dependency and one-to-one relation, PRECIS has adopted a display format, which constitutes three parts:

(i)                 Lead:  ‘Lead’ position serves as the users’ approach term, by which a user may search the index.

(ii)              Qualifier: It represent the term or set of terms which qualifies the lead term to bring it into its proper context.It provides wider context to the lead term.

(iii)            Display: It is the remaining part of the string which helps to preserve the context.

          All the terms in the string are prepared using the PRECIS table, are then rotated according to a process known as ‘Shunting’. The structure adopted for the process is as follows:

          Lead Term                                                 Qualifier


          The approach term is placed one by one in the lead term section, with the succeeding terms (if any) as qualifier and the preceding terms (if any) in the display section, displaying the context of the terms.

Example: Computerisation of libraries in India

(0)   Indian

(1)  Libraries

(2)  Computerisation

1.                INDIA

                   Libraries. Computerisation

2.         LIBRARIES                    India


3.      COMPUTERISATION             Libraries. India

2.  Predicate Transformation Format

          The Predicate Transformation Format is used when the teem representing an agent (3) appears as a lead term profixed by one of the operators 2 or  s or  t.  When such a situation arises, 2 or s or t is shifted to Display position from the Qualifier position.

3.  Inverted Format

          PRECIS makes the use of inverted format when any term is provided the role operators (4), (5) or (6) and these terms appear as Lead terms. When it happens so, the dependant elements  are presented in italics (or underlined if handwritten) after a hyphen and the terms in the Qualifier position are printed in Display position.

5.4.4    Filing Order

          PRECIS follows a two-line format for the display of  its entries, as a result it follows a distinct filing order, within broad alphabetisation. When a number of entries appear under similar lead terms, they are further arranged by the qualifiers as follows.

                    LIBRARIES                    Bangladesh

                             Personnel.  Recruitment

                   LIBRARIES                    India

                             Inter-Library Loans




with regards




easy to understand, thanks a lot



Please tel me what is the difference between biography &bibliogrphy

biography is the source of information which covers a particular person(s) life and the bibliography is the systematic list of books etc.which arrenged a manner 

thnks sir can u tell me POPSI AND PRECIS. CHAIN Procedures,KWIC,KWOC,KWAC, which year published.

thanku sir




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