., Annals of Library and Information Studies 50,4; 2003; 156- t62 CHEMICAL TECHNOLOGY LITERATURE: AN OBSOLESCENCE STUDY. B. S. Biradar B.T. Sampath Kumar Department of Library and Information Science Kuvempu University Jnana Sahyadri, Shimoga 577 451 Karnataka Obsolescence study is useful for librarians and managers. of information centers in identifying the use of periodical literature. The present study aims to examine in the light of obsolescence of literature, Annual Aging Factor (AAF), Mean Life (ML) and Utility Factor (UF):of periodicals in the field of chemistry. This is based on references appended to the articles published in Indian Journal of Chemical Technology during the year 1994, 1997 and 1999. Obsolescence of literature was studied and half-life of literature was found to be 11.8 years. Study also applied Brooke's formula for identifying Annual Aging Factor (AAF) and the average value of 'a' was found to be 0.9754 and Mean Life (ML) and Utility Factor (UF) were calculated and found to be 16.1958 and 40.65 respectively INTRODUCTION Obsolescence has become one of the important characteristics of scientific and technological literature. Obsolescence study is very useful for librarians and managers of information centers to solve the problems of space and organization of reading materials in the library with limited staff. One can also understand how far a researcher will go back to obtain a published paper in his field of interest. If a journal is less used, we say that articles published in that journal have become obsolete. Based on this, we can decide about organization of frequently and less frequently used reading materials; and if necessary, some of the less frequently used materials may be discarded from library collections. In library science literature, obsolescence refers to the fact that with age, a publication tends to be referred less number of times. Their utility as a source of information decreases with age. Age of the cited documents indicate the useful life of document. This useful life is also called the half-life of periodicals, some times expressed as the rate of obsolescence. In the last few decades, large number of studies have been conducted in this area. However, changing needs of the users and increhsing research on multidisciplinary subjects have necessitated this study on the obsolescence of rate of literature in the field of chemistry. PREVIOUS STUDIES Some of the important articles are reviewed to make the study simple and effective. Premier works like that of Brooke's [I] argued that if growth rates of output of literature and number of contributors are equal then the obsolescence rate remains constant. Kent's [2] study of obsolescence explains about the measures for determining the extent to which library materials are used and determine the storage or discarding points. Obsolescence and utility factors of periodical publications, value of halflife, mean life, utility factors of periodicals of the Institute of Radio Engineering and journals of the American Chemical Society was made by Ravichandra Rao [3]. Similar studies were also conducted by Marton [4], Sangam [5], Biradar [6] and Kannappanavar [7] on different subjects. OBJECTIVES The objectives of the paper are to examine the: i) obsolescence of chemical literature; and 156 Ann Lib Inf Stu
ii) Annual Aging Factor (AAF), Mean Life (ML) and Utility Factor (LIF). SOURCE DATA rest of the 30 % may be deposited in the dormitory section of the library. Test of exponentially of citation distribution For the present obsolescence study, the lndian Journal of Chemical Technology, a bimonthly chemistry journal published by National Institute of Science Communication and lnformation Resources (NISCAIR) was opted as the source. METHODOLOGY The present study is based on the analysis of references appended to the articles covered in the journal,.indian Journal of Chemical Technology covering three volumes (1,4, and 6) for the years 1994, 1997 and 1999. This reputed Indian Journal is published by National lnstitute of Science Communication and lnformation Resources (N I SCAI R) and reports primary investigations in the field of Chemistry The data of column number 2 and 5 in Table -1 are plotted as a frequency polygon AAi and,bb1 in Fig. 1. The curve AA1 looks like a negative exponential distribution. The Fig. 1 indicates a roughly declining trend in the frequency citation as against the cited ages. Little variation may be found with variance and the mean. The mean and variance are calculated using data presented in Table-2. c xf(x) 38465 The mean X = - = 16.1958 zf(x). 2375 C x2f(x) The variable 62 = - - (7q2 Cf04 1085375 62 = - (16.1 958)2 and its other related sub-branches. All references appended to the articles and 2375 bibliographical items like name of the author(s), title, journal volume and issue number, year of 62 = 457-262.30393 publication and pagination were recorded on S2 = 194.69607 separate paper slips. The collected data was tabulated and analysed in order to obtain the results in respect to the stated objectives. 6 = 13.9533~14 6 = 194.69607 ANALYSIS AND INTERPRETATION OF Annual Aging Factor (AA F) DATA 5'; The AAF= a has been calculated graphically Obsolescence of Journal Literature using Brooke's procedure. Table -1 gives the age wise distribution of cited literature in the field of chemistry. It shows that more number of citations (57.22%) are distributed in the age of 0-15 years. The maximum number of citations are 3 years old (5.347%) followed by 5 and 2 years (4.968 Ol0 and 4.926 % respectively). It is observed that the number of citations decreased with increase in the age except in some years the citation increased with small margin. It is also observed that 70 % of citations are 20 years old. This indicates that librarians have to maintain 20 year old periodicals in easily accessible place and Chronological Sunerlng of Journal Cltalions I-+- MI: Frequmq polygon lor dtabns.-.w... 881: Cunulatlve hequency& 1 Age In Yean Figure 1 VolS0 No 4 December 2003 157
Biradar B S and Sampath ~umar B T' Table 1 - Obsolescence of journal literature in Chemical Technology Age inyears(t) No. of Citations 2 5 74 11 7 127 111 11 8 98 97 95 86 9 5 97 77 70 72 65 67 54 4 5 4 6 43 40 46 46 3 9 2 8 32 3 9 29 22 25 2 1 24 2 8 17 12 13 14 24 2 7 19 11 12 9 12 10 13 9 3 7 4 1 5 3 3 4 Cumulative Citations 25 99 21 6 343 454 572 670 767 862 948 1043 11 40 1217 1287 1359 1424 1491 1545 1590 1636 1679 171 9 1765 181 1 1850 1878 1910 1949 1978 2000 2025 2046 2070 2098 21 15 21 27 21 40 21 54 2178 2205 2224 2235 2247 2256 2268 2278 2291 2300 2303 2310 2314 231 5 2320 2323 2326 2330 Citation in Total (t) 2375 2350 2276 2159 2032 1921 1803 1705 1608 1513 1427 1332 1235 1158 1088 101 6 951 884 830 785 739 696 656 61 0 564 525 497 465 426 397 375 350 329 305 277 260 248 235 221 197 170 140 140 1.28 119 107 97 84 75.72 65 61 60 55 52 49 L58 Ann Lib Inf Stu
Total Procedure to calculate AAF=a The data in column 5 of Table -1 were plotted on semi-log paper, as shown in Figure -2. a) On X-axis the values of citations age i.e. of 't' in year are taken starting with year t =O as base year, the values were taken from t=o to t=14; b) On Y-axis on left hand side, the value of cumulative citations from total i.e. 2375 of 0 year was taken on log scale. g) The line XY reads the values for t=o to t=l4, the value for 'a' on the line XY at the extreme right is 0.47. h) Taking this value to the left hand side, another imaginary line can also be drawn parallel to XY or X 1 Y1 to read the value for t=15 to t=29. i) The value of 'a' thus should be calculated using the following formula T(t)=a c) The resultant line by joining the maximum points on the straight line, XY was plotted; d) For convenience a parallel line to XY was drawn from the point T (t)=10,000 on this line T (t) =a=a the Annual Aging Factor. e) The'scale on left hand is graduated to find out the different values of 'a' directly from graph from 1.0 to 0.1. f) The value of 'a' at t=l directly read from the figure-2 is equal to 0.94 approximately, similarly at t=4 an a=0.79 and at t=10 Annual Aging Factor a=0.58.......... (1) l e * I l l r l l l l, l l l 0 1 2 3 5 6 7 8 91011121314 Age in years (t) Figure 2 - Annual aging factor Vol 50 No 4 December 2003
.. Birariar B S and Sarnpath ~umbr B T Table 2 - Citation data for journals in Chemical Technology Age of No. of Citations f o() Citations, X x f(x) X2 f(x) Observed cumulative Percentage 160 Ann Lib Inf Stu
The value as read directly from the graph for t=l found to be 0.94...... (2) -The value of 'a' using parallel line X1 Y1 At t=fl, a1=0.94 Applying log on both side log a1 = log 0.94 1 log a = -0.0268721 a = 0.973485 43) At t=4, A'= 0.79 Applying log on both side log a4 = log 0.79 4 log a = - 0.102372 log a = -0.025593 a = -0.974731... (4) Applying log on both side log a lo - log 0.58 10 log a - -0.236572 log a - -0.023657 a = 0.976628 The average value of a =0.9754 Thus, the average value of 'a' calculated is more accurate (as given in equation 3,4,5 and 6) than the observed one as given in equation 3 above. Half-life M.B.Line explains half life as "half the active life and this was interpreted as meaning time during which one half of the currently active literature was published". The so-called half-life of literature is compounded of its obsolescence rate and its growth rate. The half-life determined from the graph in Figure -1 is 11.8. Utility Factor (UF) The Utility Factor, U can be calculated using the following relation Applying log on both-side log a l4 = log 0.47 14 log a = -0.327982 log a = -0.02342 a = 0.976858 This relationship shows that the UF will be 40.65 when and only when AAF is high 1 'U =- 1 -a Vol 50 No 4 December 2003
Biradar B S and Sampath Kumar B T Utility Factor (U)= 40.65 FINDINGS AND CONCLUSION The following are the major findings of the study. i) A major percent of cited literature are current ones. ii) Decrease in the use of periodicals is noticed.as its age increases. iii) The average half-life of the literature is 11.8 years. iv) The average Annual Aging Factor (AAF=a) of literature is 0.9754. v) Mean life and Utility Factor is found to be 16.1958 and 40.65 respectively The result of the present study would be very useful for librarians and managers of information centers to organize the most frequently and less frequently used materials and if necessary it also helps in discarding the less frequently used materials from the library collection. It is also essential to keep in mind that before discarding any reading material from the collection of the library, such materials should be kept under observation for some time. REFERENCES 1. BROOKES (B C). Growth, utility and obsolescence of periodical literature. Journal of Documentation. 26; 4, 1970; 283-294. 2. KENT (A). Encyclopaedia of Library and lnformation Science. New York: Marcel Decker, 1987, 190-1 99. 3. RAVICHANDRA RAO (I K). Obsolescence and utility factors of periodical publications. Paper covered in DRTC seminar, 9. Paper - J, 1971. 4. MARTON (J). Obsolescence or immediacy of evidence supporting prices Hypothesis. Scientometrics. 7; 3-6, 1 985; 145-53. 5. SANGAM (S L). Obsolescence of Literature in Economics. /LA Bulletin, 25; 2, 1989. 59-61. 6. BIRADAR (B S) and VIJAYALAXMI (T). Pattern of lnformation use of Indian Neurological Scientists : A Bibliometric Study. Annals of Library Science and Documentation. 44; 4, 1 997, 1 43-1 57. 7. KANNAPPANAVAR (B U) and VIJAYAKUMAR (M). Periodical Literature of Plant and Cell Physiology: A citation Analysis study to Determine Obsolescence factors and patterns. SRELS Journal of lnformation Management. 38; 1, 2001, 81-90. Ann Lib Inf Stu