-
Leydesdorff, L.; Opthof, T.: Citation analysis with medical subject Headings (MeSH) using the Web of Knowledge : a new routine (2013)
0.01
0.009601584 = product of:
0.019203167 = sum of:
0.019203167 = product of:
0.038406335 = sum of:
0.038406335 = weight(_text_:t in 943) [ClassicSimilarity], result of:
0.038406335 = score(doc=943,freq=2.0), product of:
0.14706711 = queryWeight, product of:
3.9394085 = idf(docFreq=2338, maxDocs=44218)
0.03733228 = queryNorm
0.26114836 = fieldWeight in 943, product of:
1.4142135 = tf(freq=2.0), with freq of:
2.0 = termFreq=2.0
3.9394085 = idf(docFreq=2338, maxDocs=44218)
0.046875 = fieldNorm(doc=943)
0.5 = coord(1/2)
0.5 = coord(1/2)
-
Song, M.; Kim, S.Y.; Zhang, G.; Ding, Y.; Chambers, T.: Productivity and influence in bioinformatics : a bibliometric analysis using PubMed central (2014)
0.01
0.009601584 = product of:
0.019203167 = sum of:
0.019203167 = product of:
0.038406335 = sum of:
0.038406335 = weight(_text_:t in 1202) [ClassicSimilarity], result of:
0.038406335 = score(doc=1202,freq=2.0), product of:
0.14706711 = queryWeight, product of:
3.9394085 = idf(docFreq=2338, maxDocs=44218)
0.03733228 = queryNorm
0.26114836 = fieldWeight in 1202, product of:
1.4142135 = tf(freq=2.0), with freq of:
2.0 = termFreq=2.0
3.9394085 = idf(docFreq=2338, maxDocs=44218)
0.046875 = fieldNorm(doc=1202)
0.5 = coord(1/2)
0.5 = coord(1/2)
-
Härder, T.; Poetzsch-Heffter, A.: Bibliometrie: ein zweischneidiges Schwert (2013)
0.01
0.009601584 = product of:
0.019203167 = sum of:
0.019203167 = product of:
0.038406335 = sum of:
0.038406335 = weight(_text_:t in 3979) [ClassicSimilarity], result of:
0.038406335 = score(doc=3979,freq=2.0), product of:
0.14706711 = queryWeight, product of:
3.9394085 = idf(docFreq=2338, maxDocs=44218)
0.03733228 = queryNorm
0.26114836 = fieldWeight in 3979, product of:
1.4142135 = tf(freq=2.0), with freq of:
2.0 = termFreq=2.0
3.9394085 = idf(docFreq=2338, maxDocs=44218)
0.046875 = fieldNorm(doc=3979)
0.5 = coord(1/2)
0.5 = coord(1/2)
-
Tüür-Fröhlich, T.: ¬Eine "autoritative" Datenbank auf dem Prüfstand : der Social Sciences Citation Index (SSCI) und seine Datenqualität (2018)
0.01
0.009601584 = product of:
0.019203167 = sum of:
0.019203167 = product of:
0.038406335 = sum of:
0.038406335 = weight(_text_:t in 4591) [ClassicSimilarity], result of:
0.038406335 = score(doc=4591,freq=2.0), product of:
0.14706711 = queryWeight, product of:
3.9394085 = idf(docFreq=2338, maxDocs=44218)
0.03733228 = queryNorm
0.26114836 = fieldWeight in 4591, product of:
1.4142135 = tf(freq=2.0), with freq of:
2.0 = termFreq=2.0
3.9394085 = idf(docFreq=2338, maxDocs=44218)
0.046875 = fieldNorm(doc=4591)
0.5 = coord(1/2)
0.5 = coord(1/2)
-
Tavakolizadeh-Ravari, M.: Analysis of the long term dynamics in thesaurus developments and its consequences (2017)
0.01
0.00905246 = product of:
0.01810492 = sum of:
0.01810492 = product of:
0.03620984 = sum of:
0.03620984 = weight(_text_:t in 3081) [ClassicSimilarity], result of:
0.03620984 = score(doc=3081,freq=4.0), product of:
0.14706711 = queryWeight, product of:
3.9394085 = idf(docFreq=2338, maxDocs=44218)
0.03733228 = queryNorm
0.24621303 = fieldWeight in 3081, product of:
2.0 = tf(freq=4.0), with freq of:
4.0 = termFreq=4.0
3.9394085 = idf(docFreq=2338, maxDocs=44218)
0.03125 = fieldNorm(doc=3081)
0.5 = coord(1/2)
0.5 = coord(1/2)
- Abstract
- Die Arbeit analysiert die dynamische Entwicklung und den Gebrauch von Thesaurusbegriffen. Zusätzlich konzentriert sie sich auf die Faktoren, die die Zahl von Indexbegriffen pro Dokument oder Zeitschrift beeinflussen. Als Untersuchungsobjekt dienten der MeSH und die entsprechende Datenbank "MEDLINE". Die wichtigsten Konsequenzen sind: 1. Der MeSH-Thesaurus hat sich durch drei unterschiedliche Phasen jeweils logarithmisch entwickelt. Solch einen Thesaurus sollte folgenden Gleichung folgen: "T = 3.076,6 Ln (d) - 22.695 + 0,0039d" (T = Begriffe, Ln = natürlicher Logarithmus und d = Dokumente). Um solch einen Thesaurus zu konstruieren, muss man demnach etwa 1.600 Dokumente von unterschiedlichen Themen des Bereiches des Thesaurus haben. Die dynamische Entwicklung von Thesauri wie MeSH erfordert die Einführung eines neuen Begriffs pro Indexierung von 256 neuen Dokumenten. 2. Die Verteilung der Thesaurusbegriffe erbrachte drei Kategorien: starke, normale und selten verwendete Headings. Die letzte Gruppe ist in einer Testphase, während in der ersten und zweiten Kategorie die neu hinzukommenden Deskriptoren zu einem Thesauruswachstum führen. 3. Es gibt ein logarithmisches Verhältnis zwischen der Zahl von Index-Begriffen pro Aufsatz und dessen Seitenzahl für die Artikeln zwischen einer und einundzwanzig Seiten. 4. Zeitschriftenaufsätze, die in MEDLINE mit Abstracts erscheinen erhalten fast zwei Deskriptoren mehr. 5. Die Findablity der nicht-englisch sprachigen Dokumente in MEDLINE ist geringer als die englische Dokumente. 6. Aufsätze der Zeitschriften mit einem Impact Factor 0 bis fünfzehn erhalten nicht mehr Indexbegriffe als die der anderen von MEDINE erfassten Zeitschriften. 7. In einem Indexierungssystem haben unterschiedliche Zeitschriften mehr oder weniger Gewicht in ihrem Findability. Die Verteilung der Indexbegriffe pro Seite hat gezeigt, dass es bei MEDLINE drei Kategorien der Publikationen gibt. Außerdem gibt es wenige stark bevorzugten Zeitschriften."
-
Crespo, J.A.; Herranz, N.; Li, Y.; Ruiz-Castillo, J.: ¬The effect on citation inequality of differences in citation practices at the web of science subject category level (2014)
0.01
0.00894138 = product of:
0.01788276 = sum of:
0.01788276 = product of:
0.03576552 = sum of:
0.03576552 = weight(_text_:22 in 1291) [ClassicSimilarity], result of:
0.03576552 = score(doc=1291,freq=4.0), product of:
0.13073128 = queryWeight, product of:
3.5018296 = idf(docFreq=3622, maxDocs=44218)
0.03733228 = queryNorm
0.27358043 = fieldWeight in 1291, product of:
2.0 = tf(freq=4.0), with freq of:
4.0 = termFreq=4.0
3.5018296 = idf(docFreq=3622, maxDocs=44218)
0.0390625 = fieldNorm(doc=1291)
0.5 = coord(1/2)
0.5 = coord(1/2)
- Abstract
- This article studies the impact of differences in citation practices at the subfield, or Web of Science subject category level, using the model introduced in Crespo, Li, and Ruiz-Castillo (2013a), according to which the number of citations received by an article depends on its underlying scientific influence and the field to which it belongs. We use the same Thomson Reuters data set of about 4.4 million articles used in Crespo et al. (2013a) to analyze 22 broad fields. The main results are the following: First, when the classification system goes from 22 fields to 219 subfields the effect on citation inequality of differences in citation practices increases from ?14% at the field level to 18% at the subfield level. Second, we estimate a set of exchange rates (ERs) over a wide [660, 978] citation quantile interval to express the citation counts of articles into the equivalent counts in the all-sciences case. In the fractional case, for example, we find that in 187 of 219 subfields the ERs are reliable in the sense that the coefficient of variation is smaller than or equal to 0.10. Third, in the fractional case the normalization of the raw data using the ERs (or subfield mean citations) as normalization factors reduces the importance of the differences in citation practices from 18% to 3.8% (3.4%) of overall citation inequality. Fourth, the results in the fractional case are essentially replicated when we adopt a multiplicative approach.
-
Yan, E.: Finding knowledge paths among scientific disciplines (2014)
0.01
0.00894138 = product of:
0.01788276 = sum of:
0.01788276 = product of:
0.03576552 = sum of:
0.03576552 = weight(_text_:22 in 1534) [ClassicSimilarity], result of:
0.03576552 = score(doc=1534,freq=4.0), product of:
0.13073128 = queryWeight, product of:
3.5018296 = idf(docFreq=3622, maxDocs=44218)
0.03733228 = queryNorm
0.27358043 = fieldWeight in 1534, product of:
2.0 = tf(freq=4.0), with freq of:
4.0 = termFreq=4.0
3.5018296 = idf(docFreq=3622, maxDocs=44218)
0.0390625 = fieldNorm(doc=1534)
0.5 = coord(1/2)
0.5 = coord(1/2)
- Date
- 26.10.2014 20:22:22
-
Zhu, Q.; Kong, X.; Hong, S.; Li, J.; He, Z.: Global ontology research progress : a bibliometric analysis (2015)
0.01
0.00894138 = product of:
0.01788276 = sum of:
0.01788276 = product of:
0.03576552 = sum of:
0.03576552 = weight(_text_:22 in 2590) [ClassicSimilarity], result of:
0.03576552 = score(doc=2590,freq=4.0), product of:
0.13073128 = queryWeight, product of:
3.5018296 = idf(docFreq=3622, maxDocs=44218)
0.03733228 = queryNorm
0.27358043 = fieldWeight in 2590, product of:
2.0 = tf(freq=4.0), with freq of:
4.0 = termFreq=4.0
3.5018296 = idf(docFreq=3622, maxDocs=44218)
0.0390625 = fieldNorm(doc=2590)
0.5 = coord(1/2)
0.5 = coord(1/2)
- Date
- 20. 1.2015 18:30:22
17. 9.2018 18:22:23
-
Campanario, J.M.: Large increases and decreases in journal impact factors in only one year : the effect of journal self-citations (2011)
0.01
0.008851515 = product of:
0.01770303 = sum of:
0.01770303 = product of:
0.03540606 = sum of:
0.03540606 = weight(_text_:22 in 4187) [ClassicSimilarity], result of:
0.03540606 = score(doc=4187,freq=2.0), product of:
0.13073128 = queryWeight, product of:
3.5018296 = idf(docFreq=3622, maxDocs=44218)
0.03733228 = queryNorm
0.2708308 = fieldWeight in 4187, product of:
1.4142135 = tf(freq=2.0), with freq of:
2.0 = termFreq=2.0
3.5018296 = idf(docFreq=3622, maxDocs=44218)
0.0546875 = fieldNorm(doc=4187)
0.5 = coord(1/2)
0.5 = coord(1/2)
- Date
- 22. 1.2011 12:53:00
-
Ding, Y.: Applying weighted PageRank to author citation networks (2011)
0.01
0.008851515 = product of:
0.01770303 = sum of:
0.01770303 = product of:
0.03540606 = sum of:
0.03540606 = weight(_text_:22 in 4188) [ClassicSimilarity], result of:
0.03540606 = score(doc=4188,freq=2.0), product of:
0.13073128 = queryWeight, product of:
3.5018296 = idf(docFreq=3622, maxDocs=44218)
0.03733228 = queryNorm
0.2708308 = fieldWeight in 4188, product of:
1.4142135 = tf(freq=2.0), with freq of:
2.0 = termFreq=2.0
3.5018296 = idf(docFreq=3622, maxDocs=44218)
0.0546875 = fieldNorm(doc=4188)
0.5 = coord(1/2)
0.5 = coord(1/2)
- Date
- 22. 1.2011 13:02:21
-
Schlögl, C.: Internationale Sichtbarkeit der europäischen und insbesondere der deutschsprachigen Informationswissenschaft (2013)
0.01
0.008851515 = product of:
0.01770303 = sum of:
0.01770303 = product of:
0.03540606 = sum of:
0.03540606 = weight(_text_:22 in 900) [ClassicSimilarity], result of:
0.03540606 = score(doc=900,freq=2.0), product of:
0.13073128 = queryWeight, product of:
3.5018296 = idf(docFreq=3622, maxDocs=44218)
0.03733228 = queryNorm
0.2708308 = fieldWeight in 900, product of:
1.4142135 = tf(freq=2.0), with freq of:
2.0 = termFreq=2.0
3.5018296 = idf(docFreq=3622, maxDocs=44218)
0.0546875 = fieldNorm(doc=900)
0.5 = coord(1/2)
0.5 = coord(1/2)
- Date
- 22. 3.2013 14:04:09
-
Vieira, E.S.; Cabral, J.A.S.; Gomes, J.A.N.F.: Definition of a model based on bibliometric indicators for assessing applicants to academic positions (2014)
0.01
0.008851515 = product of:
0.01770303 = sum of:
0.01770303 = product of:
0.03540606 = sum of:
0.03540606 = weight(_text_:22 in 1221) [ClassicSimilarity], result of:
0.03540606 = score(doc=1221,freq=2.0), product of:
0.13073128 = queryWeight, product of:
3.5018296 = idf(docFreq=3622, maxDocs=44218)
0.03733228 = queryNorm
0.2708308 = fieldWeight in 1221, product of:
1.4142135 = tf(freq=2.0), with freq of:
2.0 = termFreq=2.0
3.5018296 = idf(docFreq=3622, maxDocs=44218)
0.0546875 = fieldNorm(doc=1221)
0.5 = coord(1/2)
0.5 = coord(1/2)
- Date
- 18. 3.2014 18:22:21
-
Onodera, N.; Iwasawa, M.; Midorikawa, N.; Yoshikane, F.; Amano, K.; Ootani, Y.; Kodama, T.; Kiyama, Y.; Tsunoda, H.; Yamazaki, S.: ¬A method for eliminating articles by homonymous authors from the large number of articles retrieved by author search (2011)
0.01
0.00800132 = product of:
0.01600264 = sum of:
0.01600264 = product of:
0.03200528 = sum of:
0.03200528 = weight(_text_:t in 4370) [ClassicSimilarity], result of:
0.03200528 = score(doc=4370,freq=2.0), product of:
0.14706711 = queryWeight, product of:
3.9394085 = idf(docFreq=2338, maxDocs=44218)
0.03733228 = queryNorm
0.21762364 = fieldWeight in 4370, product of:
1.4142135 = tf(freq=2.0), with freq of:
2.0 = termFreq=2.0
3.9394085 = idf(docFreq=2338, maxDocs=44218)
0.0390625 = fieldNorm(doc=4370)
0.5 = coord(1/2)
0.5 = coord(1/2)
-
Peng, T.-Q.; Zhu, J.J.H.: Where you publish matters most : a multilevel analysis of factors affecting citations of internet studies (2012)
0.01
0.00800132 = product of:
0.01600264 = sum of:
0.01600264 = product of:
0.03200528 = sum of:
0.03200528 = weight(_text_:t in 386) [ClassicSimilarity], result of:
0.03200528 = score(doc=386,freq=2.0), product of:
0.14706711 = queryWeight, product of:
3.9394085 = idf(docFreq=2338, maxDocs=44218)
0.03733228 = queryNorm
0.21762364 = fieldWeight in 386, product of:
1.4142135 = tf(freq=2.0), with freq of:
2.0 = termFreq=2.0
3.9394085 = idf(docFreq=2338, maxDocs=44218)
0.0390625 = fieldNorm(doc=386)
0.5 = coord(1/2)
0.5 = coord(1/2)
-
Ye, F.Y.; Leydesdorff, L.: ¬The "academic trace" of the performance matrix : a mathematical synthesis of the h-index and the integrated impact indicator (I3) (2014)
0.01
0.00800132 = product of:
0.01600264 = sum of:
0.01600264 = product of:
0.03200528 = sum of:
0.03200528 = weight(_text_:t in 1237) [ClassicSimilarity], result of:
0.03200528 = score(doc=1237,freq=2.0), product of:
0.14706711 = queryWeight, product of:
3.9394085 = idf(docFreq=2338, maxDocs=44218)
0.03733228 = queryNorm
0.21762364 = fieldWeight in 1237, product of:
1.4142135 = tf(freq=2.0), with freq of:
2.0 = termFreq=2.0
3.9394085 = idf(docFreq=2338, maxDocs=44218)
0.0390625 = fieldNorm(doc=1237)
0.5 = coord(1/2)
0.5 = coord(1/2)
- Abstract
- The h-index provides us with 9 natural classes which can be written as a matrix of 3 vectors. The 3 vectors are: X = (X1, X2, X3) and indicates publication distribution in the h-core, the h-tail, and the uncited ones, respectively; Y = (Y1, Y2, Y3) denotes the citation distribution of the h-core, the h-tail and the so-called "excess" citations (above the h-threshold), respectively; and Z = (Z1, Z2, Z3) = (Y1-X1, Y2-X2, Y3-X3). The matrix V = (X,Y,Z)T constructs a measure of academic performance, in which the 9 numbers can all be provided with meanings in different dimensions. The "academic trace" tr(V) of this matrix follows naturally, and contributes a unique indicator for total academic achievements by summarizing and weighting the accumulation of publications and citations. This measure can also be used to combine the advantages of the h-index and the integrated impact indicator (I3) into a single number with a meaningful interpretation of the values. We illustrate the use of tr(V) for the cases of 2 journal sets, 2 universities, and ourselves as 2 individual authors.
-
Li, R.; Chambers, T.; Ding, Y.; Zhang, G.; Meng, L.: Patent citation analysis : calculating science linkage based on citing motivation (2014)
0.01
0.00800132 = product of:
0.01600264 = sum of:
0.01600264 = product of:
0.03200528 = sum of:
0.03200528 = weight(_text_:t in 1257) [ClassicSimilarity], result of:
0.03200528 = score(doc=1257,freq=2.0), product of:
0.14706711 = queryWeight, product of:
3.9394085 = idf(docFreq=2338, maxDocs=44218)
0.03733228 = queryNorm
0.21762364 = fieldWeight in 1257, product of:
1.4142135 = tf(freq=2.0), with freq of:
2.0 = termFreq=2.0
3.9394085 = idf(docFreq=2338, maxDocs=44218)
0.0390625 = fieldNorm(doc=1257)
0.5 = coord(1/2)
0.5 = coord(1/2)
-
Kenyon, T.: Defining and measuring research impact in the humanities, social sciences and creative arts in the digital age (2014)
0.01
0.00800132 = product of:
0.01600264 = sum of:
0.01600264 = product of:
0.03200528 = sum of:
0.03200528 = weight(_text_:t in 1389) [ClassicSimilarity], result of:
0.03200528 = score(doc=1389,freq=2.0), product of:
0.14706711 = queryWeight, product of:
3.9394085 = idf(docFreq=2338, maxDocs=44218)
0.03733228 = queryNorm
0.21762364 = fieldWeight in 1389, product of:
1.4142135 = tf(freq=2.0), with freq of:
2.0 = termFreq=2.0
3.9394085 = idf(docFreq=2338, maxDocs=44218)
0.0390625 = fieldNorm(doc=1389)
0.5 = coord(1/2)
0.5 = coord(1/2)
-
McKeown, K.; Daume III, H.; Chaturvedi, S.; Paparrizos, J.; Thadani, K.; Barrio, P.; Biran, O.; Bothe, S.; Collins, M.; Fleischmann, K.R.; Gravano, L.; Jha, R.; King, B.; McInerney, K.; Moon, T.; Neelakantan, A.; O'Seaghdha, D.; Radev, D.; Templeton, C.; Teufel, S.: Predicting the impact of scientific concepts using full-text features (2016)
0.01
0.00800132 = product of:
0.01600264 = sum of:
0.01600264 = product of:
0.03200528 = sum of:
0.03200528 = weight(_text_:t in 3153) [ClassicSimilarity], result of:
0.03200528 = score(doc=3153,freq=2.0), product of:
0.14706711 = queryWeight, product of:
3.9394085 = idf(docFreq=2338, maxDocs=44218)
0.03733228 = queryNorm
0.21762364 = fieldWeight in 3153, product of:
1.4142135 = tf(freq=2.0), with freq of:
2.0 = termFreq=2.0
3.9394085 = idf(docFreq=2338, maxDocs=44218)
0.0390625 = fieldNorm(doc=3153)
0.5 = coord(1/2)
0.5 = coord(1/2)
-
Mutz, R.; Wolbring, T.; Daniel, H.-D.: ¬The effect of the "very important paper" (VIP) designation in Angewandte Chemie International Edition on citation impact : a propensity score matching analysis (2017)
0.01
0.00800132 = product of:
0.01600264 = sum of:
0.01600264 = product of:
0.03200528 = sum of:
0.03200528 = weight(_text_:t in 3792) [ClassicSimilarity], result of:
0.03200528 = score(doc=3792,freq=2.0), product of:
0.14706711 = queryWeight, product of:
3.9394085 = idf(docFreq=2338, maxDocs=44218)
0.03733228 = queryNorm
0.21762364 = fieldWeight in 3792, product of:
1.4142135 = tf(freq=2.0), with freq of:
2.0 = termFreq=2.0
3.9394085 = idf(docFreq=2338, maxDocs=44218)
0.0390625 = fieldNorm(doc=3792)
0.5 = coord(1/2)
0.5 = coord(1/2)
-
Farys, R.; Wolbring, T.: Matched control groups for modeling events in citation data : an illustration of nobel prize effects in citation networks (2017)
0.01
0.00800132 = product of:
0.01600264 = sum of:
0.01600264 = product of:
0.03200528 = sum of:
0.03200528 = weight(_text_:t in 3796) [ClassicSimilarity], result of:
0.03200528 = score(doc=3796,freq=2.0), product of:
0.14706711 = queryWeight, product of:
3.9394085 = idf(docFreq=2338, maxDocs=44218)
0.03733228 = queryNorm
0.21762364 = fieldWeight in 3796, product of:
1.4142135 = tf(freq=2.0), with freq of:
2.0 = termFreq=2.0
3.9394085 = idf(docFreq=2338, maxDocs=44218)
0.0390625 = fieldNorm(doc=3796)
0.5 = coord(1/2)
0.5 = coord(1/2)
