-
Egghe, L.; Rousseau, R.: ¬The Hirsch index of a shifted Lotka function and its relation with the impact factor (2012)
0.03
0.031524464 = product of:
0.06304893 = sum of:
0.06304893 = product of:
0.09457339 = sum of:
0.041649207 = weight(_text_:c in 243) [ClassicSimilarity], result of:
0.041649207 = score(doc=243,freq=2.0), product of:
0.15612034 = queryWeight, product of:
3.4494052 = idf(docFreq=3817, maxDocs=44218)
0.045260075 = queryNorm
0.2667763 = fieldWeight in 243, product of:
1.4142135 = tf(freq=2.0), with freq of:
2.0 = termFreq=2.0
3.4494052 = idf(docFreq=3817, maxDocs=44218)
0.0546875 = fieldNorm(doc=243)
0.052924186 = weight(_text_:h in 243) [ClassicSimilarity], result of:
0.052924186 = score(doc=243,freq=12.0), product of:
0.11244635 = queryWeight, product of:
2.4844491 = idf(docFreq=10020, maxDocs=44218)
0.045260075 = queryNorm
0.47066164 = fieldWeight in 243, product of:
3.4641016 = tf(freq=12.0), with freq of:
12.0 = termFreq=12.0
2.4844491 = idf(docFreq=10020, maxDocs=44218)
0.0546875 = fieldNorm(doc=243)
0.6666667 = coord(2/3)
0.5 = coord(1/2)
- Abstract
- Based on earlier results about the shifted Lotka function, we prove an implicit functional relation between the Hirsch index (h-index) and the total number of sources (T). It is shown that the corresponding function, h(T), is concavely increasing. Next, we construct an implicit relation between the h-index and the impact factor IF (an average number of items per source). The corresponding function h(IF) is increasing and we show that if the parameter C in the numerator of the shifted Lotka function is high, then the relation between the h-index and the impact factor is almost linear.
- Object
- h-index
-
Egghe, L.; Guns, R.; Rousseau, R.; Leuven, K.U.: Erratum (2012)
0.01
0.010220192 = product of:
0.020440385 = sum of:
0.020440385 = product of:
0.061321154 = sum of:
0.061321154 = weight(_text_:22 in 4992) [ClassicSimilarity], result of:
0.061321154 = score(doc=4992,freq=2.0), product of:
0.15849307 = queryWeight, product of:
3.5018296 = idf(docFreq=3622, maxDocs=44218)
0.045260075 = queryNorm
0.38690117 = fieldWeight in 4992, product of:
1.4142135 = tf(freq=2.0), with freq of:
2.0 = termFreq=2.0
3.5018296 = idf(docFreq=3622, maxDocs=44218)
0.078125 = fieldNorm(doc=4992)
0.33333334 = coord(1/3)
0.5 = coord(1/2)
- Date
- 14. 2.2012 12:53:22
-
Egghe, L.; Rousseau, R.: ¬An h-index weighted by citation impact (2008)
0.01
0.009202467 = product of:
0.018404935 = sum of:
0.018404935 = product of:
0.0552148 = sum of:
0.0552148 = weight(_text_:h in 695) [ClassicSimilarity], result of:
0.0552148 = score(doc=695,freq=10.0), product of:
0.11244635 = queryWeight, product of:
2.4844491 = idf(docFreq=10020, maxDocs=44218)
0.045260075 = queryNorm
0.4910324 = fieldWeight in 695, product of:
3.1622777 = tf(freq=10.0), with freq of:
10.0 = termFreq=10.0
2.4844491 = idf(docFreq=10020, maxDocs=44218)
0.0625 = fieldNorm(doc=695)
0.33333334 = coord(1/3)
0.5 = coord(1/2)
- Abstract
- An h-type index is proposed which depends on the obtained citations of articles belonging to the h-core. This weighted h-index, denoted as hw, is presented in a continuous setting and in a discrete one. It is shown that in a continuous setting the new index enjoys many good properties. In the discrete setting some small deviations from the ideal may occur.
- Object
- h-index
-
Rousseau, R.; Ye, F.Y.: ¬A proposal for a dynamic h-type index (2008)
0.01
0.009202467 = product of:
0.018404935 = sum of:
0.018404935 = product of:
0.0552148 = sum of:
0.0552148 = weight(_text_:h in 2351) [ClassicSimilarity], result of:
0.0552148 = score(doc=2351,freq=10.0), product of:
0.11244635 = queryWeight, product of:
2.4844491 = idf(docFreq=10020, maxDocs=44218)
0.045260075 = queryNorm
0.4910324 = fieldWeight in 2351, product of:
3.1622777 = tf(freq=10.0), with freq of:
10.0 = termFreq=10.0
2.4844491 = idf(docFreq=10020, maxDocs=44218)
0.0625 = fieldNorm(doc=2351)
0.33333334 = coord(1/3)
0.5 = coord(1/2)
- Abstract
- A time-dependent h-type indicator is proposed. This indicator depends on the size of the h-core, the number of citations received, and recent change in the value of the h-index. As such, it tries to combine in a dynamic way older information about the source (e.g., a scientist or research institute that is evaluated) with recent information.
- Object
- h-index
-
Guns, R.; Rousseau, R.: Simulating growth of the h-index (2009)
0.01
0.008820698 = product of:
0.017641395 = sum of:
0.017641395 = product of:
0.052924186 = sum of:
0.052924186 = weight(_text_:h in 2717) [ClassicSimilarity], result of:
0.052924186 = score(doc=2717,freq=12.0), product of:
0.11244635 = queryWeight, product of:
2.4844491 = idf(docFreq=10020, maxDocs=44218)
0.045260075 = queryNorm
0.47066164 = fieldWeight in 2717, product of:
3.4641016 = tf(freq=12.0), with freq of:
12.0 = termFreq=12.0
2.4844491 = idf(docFreq=10020, maxDocs=44218)
0.0546875 = fieldNorm(doc=2717)
0.33333334 = coord(1/3)
0.5 = coord(1/2)
- Abstract
- Temporal growth of the h-index in a diachronous cumulative time series is predicted to be linear by Hirsch (2005), whereas other models predict a concave increase. Actual data generally yield a linear growth or S-shaped growth. We study the h-index's growth in computer simulations of the publication-citation process. In most simulations the h-index grows linearly in time. Only occasionally does an S-shape occur, while in our simulations a concave increase is very rare. The latter is often signalled by the occurrence of plateaus - periods of h-index stagnation. Several parameters and their influence on the h-index's growth are determined and discussed.
-
Rousseau, R.; Jin, B.: ¬The age-dependent h-type AR**2-index : basic properties and a case study (2008)
0.01
0.0061732023 = product of:
0.012346405 = sum of:
0.012346405 = product of:
0.037039213 = sum of:
0.037039213 = weight(_text_:h in 2638) [ClassicSimilarity], result of:
0.037039213 = score(doc=2638,freq=8.0), product of:
0.11244635 = queryWeight, product of:
2.4844491 = idf(docFreq=10020, maxDocs=44218)
0.045260075 = queryNorm
0.32939452 = fieldWeight in 2638, product of:
2.828427 = tf(freq=8.0), with freq of:
8.0 = termFreq=8.0
2.4844491 = idf(docFreq=10020, maxDocs=44218)
0.046875 = fieldNorm(doc=2638)
0.33333334 = coord(1/3)
0.5 = coord(1/2)
- Abstract
- Hirsch-type indices are studied with special attention to the AR**2-index introduced by Jin. The article consists of two parts: a theoretical part and a practical illustration. In the theoretical part, we recall the definition of the AR**2-index and show that an alternative definition, the so-called AR**2,1, does not have the properties expected for this type of index. A practical example shows the existence of some of these mathematical properties and illustrates the difference between different h-type indices. Clearly the h-index itself is the most robust of all. It is shown that excluding so-called non-WoS source articles may have a significant influence on the R-and, especially, the g-index.
- Object
- h-index
-
Egghe, L.; Rousseau, R.: Averaging and globalising quotients of informetric and scientometric data (1996)
0.01
0.0061321156 = product of:
0.012264231 = sum of:
0.012264231 = product of:
0.03679269 = sum of:
0.03679269 = weight(_text_:22 in 7659) [ClassicSimilarity], result of:
0.03679269 = score(doc=7659,freq=2.0), product of:
0.15849307 = queryWeight, product of:
3.5018296 = idf(docFreq=3622, maxDocs=44218)
0.045260075 = queryNorm
0.23214069 = fieldWeight in 7659, product of:
1.4142135 = tf(freq=2.0), with freq of:
2.0 = termFreq=2.0
3.5018296 = idf(docFreq=3622, maxDocs=44218)
0.046875 = fieldNorm(doc=7659)
0.33333334 = coord(1/3)
0.5 = coord(1/2)
- Source
- Journal of information science. 22(1996) no.3, S.165-170
-
Asonuma, A.; Fang, Y.; Rousseau, R.: Reflections on the age distribution of Japanese scientists (2006)
0.01
0.0061321156 = product of:
0.012264231 = sum of:
0.012264231 = product of:
0.03679269 = sum of:
0.03679269 = weight(_text_:22 in 5270) [ClassicSimilarity], result of:
0.03679269 = score(doc=5270,freq=2.0), product of:
0.15849307 = queryWeight, product of:
3.5018296 = idf(docFreq=3622, maxDocs=44218)
0.045260075 = queryNorm
0.23214069 = fieldWeight in 5270, product of:
1.4142135 = tf(freq=2.0), with freq of:
2.0 = termFreq=2.0
3.5018296 = idf(docFreq=3622, maxDocs=44218)
0.046875 = fieldNorm(doc=5270)
0.33333334 = coord(1/3)
0.5 = coord(1/2)
- Date
- 22. 7.2006 15:26:24
-
Colebunders, R.; Kenyon, C.; Rousseau, R.: Increase in numbers and proportions of review articles in Tropical Medicine, Infectious Diseases, and oncology (2014)
0.01
0.0059498874 = product of:
0.011899775 = sum of:
0.011899775 = product of:
0.035699323 = sum of:
0.035699323 = weight(_text_:c in 1189) [ClassicSimilarity], result of:
0.035699323 = score(doc=1189,freq=2.0), product of:
0.15612034 = queryWeight, product of:
3.4494052 = idf(docFreq=3817, maxDocs=44218)
0.045260075 = queryNorm
0.22866541 = fieldWeight in 1189, product of:
1.4142135 = tf(freq=2.0), with freq of:
2.0 = termFreq=2.0
3.4494052 = idf(docFreq=3817, maxDocs=44218)
0.046875 = fieldNorm(doc=1189)
0.33333334 = coord(1/3)
0.5 = coord(1/2)
-
Egghe, L.; Liang, L.; Rousseau, R.: ¬A relation between h-index and impact factor in the power-law model (2009)
0.01
0.005820151 = product of:
0.011640302 = sum of:
0.011640302 = product of:
0.034920905 = sum of:
0.034920905 = weight(_text_:h in 6759) [ClassicSimilarity], result of:
0.034920905 = score(doc=6759,freq=4.0), product of:
0.11244635 = queryWeight, product of:
2.4844491 = idf(docFreq=10020, maxDocs=44218)
0.045260075 = queryNorm
0.31055614 = fieldWeight in 6759, product of:
2.0 = tf(freq=4.0), with freq of:
4.0 = termFreq=4.0
2.4844491 = idf(docFreq=10020, maxDocs=44218)
0.0625 = fieldNorm(doc=6759)
0.33333334 = coord(1/3)
0.5 = coord(1/2)
- Object
- h-index
-
Egghe, L.; Guns, R.; Rousseau, R.: Thoughts on uncitedness : Nobel laureates and Fields medalists as case studies (2011)
0.00
0.004365113 = product of:
0.008730226 = sum of:
0.008730226 = product of:
0.026190678 = sum of:
0.026190678 = weight(_text_:h in 4994) [ClassicSimilarity], result of:
0.026190678 = score(doc=4994,freq=4.0), product of:
0.11244635 = queryWeight, product of:
2.4844491 = idf(docFreq=10020, maxDocs=44218)
0.045260075 = queryNorm
0.2329171 = fieldWeight in 4994, product of:
2.0 = tf(freq=4.0), with freq of:
4.0 = termFreq=4.0
2.4844491 = idf(docFreq=10020, maxDocs=44218)
0.046875 = fieldNorm(doc=4994)
0.33333334 = coord(1/3)
0.5 = coord(1/2)
- Abstract
- Contrary to what one might expect, Nobel laureates and Fields medalists have a rather large fraction (10% or more) of uncited publications. This is the case for (in total) 75 examined researchers from the fields of mathematics (Fields medalists), physics, chemistry, and physiology or medicine (Nobel laureates). We study several indicators for these researchers, including the h-index, total number of publications, average number of citations per publication, the number (and fraction) of uncited publications, and their interrelations. The most remarkable result is a positive correlation between the h-index and the number of uncited articles. We also present a Lotkaian model, which partially explains the empirically found regularities.
-
Ahlgren, P.; Jarneving, B.; Rousseau, R.: Requirements for a cocitation similarity measure, with special reference to Pearson's correlation coefficient (2003)
0.00
0.0040880768 = product of:
0.0081761535 = sum of:
0.0081761535 = product of:
0.02452846 = sum of:
0.02452846 = weight(_text_:22 in 5171) [ClassicSimilarity], result of:
0.02452846 = score(doc=5171,freq=2.0), product of:
0.15849307 = queryWeight, product of:
3.5018296 = idf(docFreq=3622, maxDocs=44218)
0.045260075 = queryNorm
0.15476047 = fieldWeight in 5171, product of:
1.4142135 = tf(freq=2.0), with freq of:
2.0 = termFreq=2.0
3.5018296 = idf(docFreq=3622, maxDocs=44218)
0.03125 = fieldNorm(doc=5171)
0.33333334 = coord(1/3)
0.5 = coord(1/2)
- Date
- 9. 7.2006 10:22:35
-
Kretschmer, H.; Rousseau, R.: Author inflation leads to a breakdown of Lotka's law : in and out of context (2001)
0.00
0.0030866012 = product of:
0.0061732023 = sum of:
0.0061732023 = product of:
0.018519606 = sum of:
0.018519606 = weight(_text_:h in 5205) [ClassicSimilarity], result of:
0.018519606 = score(doc=5205,freq=2.0), product of:
0.11244635 = queryWeight, product of:
2.4844491 = idf(docFreq=10020, maxDocs=44218)
0.045260075 = queryNorm
0.16469726 = fieldWeight in 5205, product of:
1.4142135 = tf(freq=2.0), with freq of:
2.0 = termFreq=2.0
2.4844491 = idf(docFreq=10020, maxDocs=44218)
0.046875 = fieldNorm(doc=5205)
0.33333334 = coord(1/3)
0.5 = coord(1/2)
-
Impe, S. van; Rousseau, R.: Web-to-print citations and the humanities (2006)
0.00
0.0030866012 = product of:
0.0061732023 = sum of:
0.0061732023 = product of:
0.018519606 = sum of:
0.018519606 = weight(_text_:h in 82) [ClassicSimilarity], result of:
0.018519606 = score(doc=82,freq=2.0), product of:
0.11244635 = queryWeight, product of:
2.4844491 = idf(docFreq=10020, maxDocs=44218)
0.045260075 = queryNorm
0.16469726 = fieldWeight in 82, product of:
1.4142135 = tf(freq=2.0), with freq of:
2.0 = termFreq=2.0
2.4844491 = idf(docFreq=10020, maxDocs=44218)
0.046875 = fieldNorm(doc=82)
0.33333334 = coord(1/3)
0.5 = coord(1/2)
- Source
- Information - Wissenschaft und Praxis. 57(2006) H.8, S.422-426
