133,656 research outputs found
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe 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
Dispelling the Myths Behind First-author Citation Counts
No full textWe 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
Ficedula hypoleuca subsp. tomensis Johansen 1916
No full textF. h. tomensis (Johansen, 1916) Muscicapa atricapilla tomensis Johansen, 1916: 101 [new name for Muscicapa atricapilla sibirica Khakhlov, 1915]. Type locality and material: as for sibirica (see above). The name tomensis Johansen, 1916 is a replacement name for sibirica Khakhlov, 1915, the latter having been published in Muscicapa where it is a junior primary homonym of Muscicapa sibirica Gmelin, 1789 and so permanently invalid (Article 57.2 of the Code). This subspecies is considered to be clearly diagnosable from nominate hypoleuca (e.g., Johansen 1954), although the location of and circumstances in their contact Zone is poorly understood. It occurs in the taiga of west Siberia, from the Ural Mountains to the Yenisey River, wintering in east Africa (Clements et al. 2015).Published as part of Salvador, Rodrigo B., Jeugd, Henk Van Der & Tomotani, Barbara M., 2017, Taxonomy of the European Pied Flycatcher Ficedula hypoleuca (Aves: Muscicapidae), pp. 171-182 in Zootaxa 4291 (1) on page 175, DOI: 10.11646/zootaxa.4291.1.10, http://zenodo.org/record/82932
Neohydatothrips rapoporti Johansen
No full textNeohydatothrips rapoporti Johansen Neohydatothrips rapoporti Johansen, 1983: 110. Female macroptera. Colour: mainly yellowish brown, ocellar area striate, anterior margin of mesonotum and metanotum, pronotal blotch and antecostal ridges also anterolateral areas on tergites III–VII brown; abdominal tergites II–IV and VII–IX brown; antennal segment I light brown to brown, II brown, III light brown with darker apex, IV light brown with base and apex brown, V light brown with brown base and apical half, VI–VIII brown; legs yellow with femora and tibiae shaded brown medially; fore wing brown with one sub-apical pale area. Structure: Occipital apodeme not confluent with posterior margin of eyes; pronotum transversely striate with no internal markings, pronotal blotch distinct; mesonotum transversely striate; metanotal striae transverse on anterior half, longitudinal on posterior half; metasternal plate with shallow emargination; comb of microtrichia incomplete on tergites III–VI, complete on VII–VIII; tergite IX with 2 pairs of mid-dorsal setae. Material studied. None. Comments. This species was based on several specimens collected in Hidalgo, Mexico. It is described as having the occipital apodeme close to the posterior margins of the compound eyes, and one small pale spot subbasally on the fore wing. However, Johansen’s original illustrations, and a photograph presumably of a specimen from the type series published subsequently (Johansen-Naime & Mojica-Guzmán 2009), show the occipital apodeme far from the compound eyes and one defined pale band subapically on the fore wing. It is these character states that are used here to distinguish N. rapoporti from its congeners. Apart from the type specimens, several other individuals have been collected on Buddleja leaves, which is probably its host plant (Johansen-Naime & Mojica-Guzmán 2009). The species is unique in being mostly yellowish brown but with bicoloured fore wings.Published as part of Lima, Élison Fabrício B. & Mound, Laurence A., 2016, Species-richness in Neotropical Sericothripinae (Thysanoptera: Thripidae), pp. 1-45 in Zootaxa 4162 (1) on pages 36-37, DOI: 10.11646/zootaxa.4162.1.1, http://zenodo.org/record/26386
Further evidence on the size and power of the Bierens and Johansen cointegration procedures
No full textAlthough both the Johansen (1991, 1994) trace test and Bierens (1997a,b) nonparametric lambda-min test for cointegration have good size properties in Monte Carlo studies by Hubrich, Lutkepohl, and Saikkonen (2001) and Boswijk, Lucas, and Taylor (2000), the Bierens test has very low power. In contrast, Bierens reports good power for his procedure. Meanwhile, Hubrich et al. and Boswijk et al. do not include Bierens' companion method for estimating the number of cointegrating vectors, nor do they investigate the effect of serial correlation on Bierens'' test. In the present paper, inclusion of the estimation step does not significantly degrade size of the Bierens procedure, even with serial correlation, but power is not improved. Serial correlation does degrade the size of the Johansen test, but it remains superior. Analysis of Bierens'' (1997b) Monte Carlo results suggests that their indication of high power reflects the test''s lack of scale invariance.Monte Carlo
The lack of design quality focus in construction: a case for examining suitable design processes
No full textA large number of projects in UK construction now involve contractor-led design and are thus very different from the traditional approach which formed the basis of the original Royal Institute of British Architects (RIBA) Outline Plan of Work. Such integrated and contractor-led approaches support the reform agenda of the late 1990s that was introduced to tackle process inefficiency. However, within the design professions there has been concern that this resulted in buildings that were designed-down to a cost rather than designed-up to a value. An attempt to address this resulted in the formation of the Commission for Architecture and Built Environment (CABE) in 1999 and the launch, in 2003, of the Design Quality Indicator (DQI) which measures how well a building satisfies stakeholders. This paper presents the early phases of doctoral research which will examine the impact of integrated design management approaches upon Design Quality
Neohydatothrips aztecus Johansen, stat. rev.
No full text<i>Neohydatothrips aztecus</i> Johansen stat. rev. <p> <i>Neohydatothrips aztecus</i> Johansen, 1983: 113.</p> <p> <i>Female macroptera</i>. Colour: mainly yellowish brown, ocellar area brown, also pronotal blotch, anterior third and lateral areas of mesonotum and metanotum, antecostal ridges and anterolateral areas on tergites II–VI and VII–IX; fore wing grey; antennal segments I–II brown, III yellow with base brown and apical third light brown, IV brown with basal third yellow, V brown with small yellow ring at base, VI–VIII brown.</p> <p>Structure: Occipital apodeme not confluent with posterior margin of eyes, ocellar area transversely striate; pronotum transversely striate with distinct blotch; mesonotum transversely striate; metanotum longitudinally reticulate; metasternal plate with shallow emargination; fore wing second vein with 2 setae; comb of microtrichia incomplete on tergites II–VI and complete on VII–VIII; tergite IX with 2 pairs of mid-dorsal setae.</p> <p> <b>Material studied</b>. None.</p> <p> <b>Comments</b>. This species was described from 4 females and 2 males collected in Pedregal de San Ángel, Mexico City, Mexico. Although placed in synonymy with <i>N. signifer</i> by Mound & Marullo (1996) based on the similarities on colouration and structure, it can be distinguished by the brown tergites VII–IX (Johansen 1983). Moreover, it was described as having two setae on the second vein of the fore wing in contrast to the single seta found in <i>N. burungae</i>.</p>Published as part of <i>Lima, Élison Fabrício B. & Mound, Laurence A., 2016, Species-richness in Neotropical Sericothripinae (Thysanoptera: Thripidae), pp. 1-45 in Zootaxa 4162 (1)</i> on pages 12-13, DOI: 10.11646/zootaxa.4162.1.1, <a href="http://zenodo.org/record/263866">http://zenodo.org/record/263866</a>
Empirical Transition Matrix of Multi-State Models: The etm Package
No full textMulti-State models provide a relevant framework for modelling complex event histories. Quantities of interest are the transition probabilities that can be estimated by the empirical transition matrix, that is also referred to as the Aalen-Johansen estimator. In this paper, we present the R package etm that computes and displays the transition probabilities. etm also features a Greenwood-type estimator of the covariance matrix. The use of the package is illustrated through a prominent example in bone marrow transplant for leukaemia patients.
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