1,720,985 research outputs found
phenoBayes: Bayesian hierarchical models for estimating spatial and temporal patterns in vegetation phenology from Landsat time series
No full text<p><strong>phenoBayes:</strong> Bayesian hierarchical models for estimating spatial and temporal patterns in vegetation phenology from Landsat time series</p>
<p>This repository describes and documents a set of models used to estimate spatial and temporal patterns in vegetation phenology from Landsat data. The code was used for a manuscript submitted as: Senf, C., Pflugmacher D., Heurich, M. and Krueger T. (2017) A Bayesian hierarchical model for estimating spatial and temporal variation in vegetation phenology from Landsat time series. <em>Remote Sensing of Environment</em>. DOI: 10.1016/j.rse.2017.03.020</p>
Manually interpreted reference data on forest disturbances across Europe
No full textDescription
Disturbance reference data collected via TimeSync (Cohen et al. 2010) for 19,996 plots across 35 countries in continental Europe. The exact methods and response design are described in Senf et al. 2018.
A NOTE OF CAUTION: While we recorded an agent label (i.e., the cause of disturbance, including harvest, biotic, breakage, fire), the agent attribution is highly unreliable and depends strongly on the availability of high resolution imagery during interpretation.
Columns
- country: the country the plots are located in
- plotid: a country-specific id (i.e., starting with 1 for each country)
- disturbance_n: number of disturbances detected during the period 1986-2018 (maximum of 3; 0 if not disturbance detected)
- year_disturbance_1: Year of the first disturbance detected (NA if no disturbance detected)
- year_disturbance_2: Year of the second disturbance detected (NA if only one disturbance detected)
- year_disturbance_3: Year of the third disturbance detected (NA if only one or two disturbance(s) detected)
- agent_disturbance_1: Agent of the first disturbance (NA if no disturbance detected; SEE NOTE OF CAUTION!)
- agent_disturbance_2: Agent of the second disturbance detected (NA if only one disturbance detected)
- agent_disturbance_3: Agent of the third disturbance detected (NA if only one or two disturbance(s) detected)
- severity_disturbance_1: Severity of the first disturbance, expressed as stand-replacing (SR; all canopy removed during disturbance event leading to non-treed land cover) or non-stand-replacing (NSR; residual canopy cover after disturbances leading to treed land cover). NA if not disturbance detected.
- severity_disturbance_2: Severity of the second disturbance (see description above; NA if only one disturbance detected)
- severity_disturbance_3: Severity of the first disturbance (see description above; NA if only one or two disturbance(s) detected)
References
Cohen, W.B., Yang, Z., Kennedy, R., 2010. Detecting trends in forest disturbance and recovery using yearly Landsat time series: 2. TimeSync — Tools for calibration and validation. Remote Sensing of Environment 114, 2911–2924. https://doi.org/10.1016/j.rse.2010.07.010
Senf, C., Pflugmacher, D., Zhiqiang, Y., Sebald, J., Knorrn, J., Neumann, M., Hostert, P., Seidl, R., 2018. Canopy mortality has doubled across Europe’s temperate forests in the last three decades. Nature Communications 9, 4978. https://doi.org/10.1038/s41467-018-07539-6
</p
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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
corneliussenf/TimeSyncEurope: Final data and code of the published paper.
No full textNo description provided
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe 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
corneliussenf/CanopyHeightDiversity: First release
No full textCode and part of the data that was used to calculate canopy height diversity in two German protected areas
- …
