1,720,965 research outputs found
Species limits in antbirds (Aves: Passeriformes: Thamnophilidae): an evaluation of Frederickena unduligera (Undulated Antshrike) based on vocalizations
No full textIsler, Morton L., Isler, Phyllis R., Whitney, Bret M., Zimmer, Kevin J., Whittaker, Andrew (2009): Species limits in antbirds (Aves: Passeriformes: Thamnophilidae): an evaluation of Frederickena unduligera (Undulated Antshrike) based on vocalizations. Zootaxa 2305 (1): 61-68, DOI: 10.11646/zootaxa.2305.1.5, URL: https://biotaxa.org/Zootaxa/article/view/zootaxa.2305.1.
FIGURE 3 in Species limits in Antbirds (Aves: Passeriformes: Thamnophilidae): an evaluation of Plumbeous Antvireo (Dysithamnus plumbeus) based on vocalizations
No full textFIGURE 3. Calls of Dysithamnus leucostictus and D. plumbeus. (A) Examples of common calls of D. leucostictus tucuyensis. Rancho Grande, Aragua, Venezuela (P. Schwartz ML 61928). (B) Variant of D. l. tucuyensis common call, same recording. (C–E) Representative examples of common calls of D. l. leucostictus. (C) Downslurred call (most prevalent). Volcán Sumaco, Napo, Ecuador (B. Whitney ML 50887). (D) Rounded call. Volcán Sumaco, Napo, Ecuador (B. Whitney ML 50883). (E) Upslurred call, same recording. (F) D. l. leucostictus Flat call. Volcán Sumaco, Napo, Ecuador (B. Whitney ML 51122). (G) D. l. tucuyensis Downslurred call. Colonia Tovar, Aragua, Venezuela (ISL-BMW.017:27). (H) D. l. leucostictus Short downslurred call. Volcán Sumaco, Napo, Ecuador (B. Whitney ML 51122). (I) D. l. tucuyensis Short downslurred call. Rancho Grande, Aragua, Venezuela (B. Whitney ISL-BMW.018:07). (J) D. l. tucuyensis Complex call to be verified (see text). Montalban, Carabobo Venezuela (P. Boesman ISL-MISC.G.044). (K–M) Representative examples of calls of D. plumbeus. (K) Simple calls. Parque Estadual Florestal do Rio Doce, Minas Gerais, Brazil (M. Maldonado-Coelho ISL-MISC.G.0038). (L) Harsh chirr, same recording. (M) Short trills. Parque Estadual Florestal do Rio Doce, Minas Gerais, Brazil (M. Maldonado-Coelho ISL-MISC.G.0039). Nomenclature follows recommendations of this paper.Published as part of Isler, Morton L., Isler, Phyllis R. & Whitney, Bret M., 2008, Species limits in Antbirds (Aves: Passeriformes: Thamnophilidae): an evaluation of Plumbeous Antvireo (Dysithamnus plumbeus) based on vocalizations, pp. 60-68 in Zootaxa 1726 (1) on page 64, DOI: 10.11646/zootaxa.1726.1.5, http://zenodo.org/record/510786
FIGURE 1 in Species limits in antbirds (Aves: Passeriformes: Thamnophilidae): an evaluation of Frederickena unduligera (Undulated Antshrike) based on vocalizations
No full textFIGURE 1. Geographic ranges. Locations documented by specimens, vocal recordings, or published sight records are assigned to geographic sectors (Isler 1997) and are identified by open circles. Circles in sectors in which loudsong recordings were available are filled in solidly. Except where they follow rivers, dotted lines that separate taxa are symbolic because actual geographic limits are unknown. Circles numbered 1 through 4 are type localities. 1 = Frederickena u. unduligera. 2 = F. fulva. 3 = F. u. diversa. 4 = F. u. pallida. Circles numbered 5 identify sites south of the Río Marañón in which loudsongs having the characteristics of F. fulva were recorded (see text). Circles numbered 6 denote sites where populations remain to be identified by vocal recordings (see text). Nomenclature follows recommendations of this paper.Published as part of Isler, Morton L., Isler, Phyllis R., Whitney, Bret M., Zimmer, Kevin J. & Whittaker, Andrew, 2009, Species limits in antbirds (Aves: Passeriformes: Thamnophilidae): an evaluation of Frederickena unduligera (Undulated Antshrike) based on vocalizations, pp. 61-68 in Zootaxa 2305 (1) on page 63, DOI: 10.11646/zootaxa.2305.1.5, http://zenodo.org/record/530572
FIGURE 3 in Species limits in antbirds (Aves: Passeriformes: Thamnophilidae): an evaluation of Frederickena unduligera (Undulated Antshrike) based on vocalizations
No full textFIGURE 3. Calls of Frederickena unduligera and F. fulva. (A) F. u. unduligera snarl. Parque Nacional de Jaú, Amazonas, Brazil (S. Borges ISL-AW.020:29). (B–D) F. u. pallida. (B) whistle. Tupana Lodge, Amazonas, Brazil (A. Whittaker ISL-AW.020:28). (C) short whistle. Igarapé Santa Maria, Amazonas, Brazil (B. Whitney ISL-BMW.184:55). (D) whistle-snarl. Tupana Lodge, Amazonas, Brazil (A. Whittaker ISL-AW.020:21). (E–H) F. u. diversa. (E) whistle. Parque Nacional da Serra do Divisor, Acre, Brazil (B. Whitney ISL-BMW. 126:07). (F) whistle-snarl. same recording. (G) snarl. same recording. (H) rattle. same location (B. Whitney ISL-BMW. 126:04). (I–K) F. fulva. (I) whistle. Kapawi Lodge, Pastaza, Peru (B. Whitney ISL-BMW.157:08). (J) whistle-snarl. same recording. (K) snarl. same location (B. Whitney ISL-BMW.153:08).Published as part of Isler, Morton L., Isler, Phyllis R., Whitney, Bret M., Zimmer, Kevin J. & Whittaker, Andrew, 2009, Species limits in antbirds (Aves: Passeriformes: Thamnophilidae): an evaluation of Frederickena unduligera (Undulated Antshrike) based on vocalizations, pp. 61-68 in Zootaxa 2305 (1) on page 66, DOI: 10.11646/zootaxa.2305.1.5, http://zenodo.org/record/530572
FIGURE 1 in Species limits in antbirds (Aves: Passeriformes: Thamnophilidae): an evaluation of Frederickena unduligera (Undulated Antshrike) based on vocalizations
No full textFIGURE 1. Geographic ranges. Locations documented by specimens, vocal recordings, or published sight records are assigned to geographic sectors (Isler 1997) and are identified by open circles. Circles in sectors in which loudsong recordings were available are filled in solidly. Except where they follow rivers, dotted lines that separate taxa are symbolic because actual geographic limits are unknown. Circles numbered 1 through 4 are type localities. 1 = Frederickena u. unduligera. 2 = F. fulva. 3 = F. u. diversa. 4 = F. u. pallida. Circles numbered 5 identify sites south of the Río Marañón in which loudsongs having the characteristics of F. fulva were recorded (see text). Circles numbered 6 denote sites where populations remain to be identified by vocal recordings (see text). Nomenclature follows recommendations of this paper.Published as part of Isler, Morton L., Isler, Phyllis R., Whitney, Bret M., Zimmer, Kevin J. & Whittaker, Andrew, 2009, Species limits in antbirds (Aves: Passeriformes: Thamnophilidae): an evaluation of Frederickena unduligera (Undulated Antshrike) based on vocalizations, pp. 61-68 in Zootaxa 2305 (1) on page 63, DOI: 10.11646/zootaxa.2305.1.5, http://zenodo.org/record/530572
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
- …
