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Sequele psicopatologiche in pazienti affetti da malattie di Hodgkin "off-therapy": riflessioni su alcuni casi clinici trattati in psicoterapia
No full textComparing data mining and deterministic pedology to assess the frequency of WRB reference soil groups in the legend of small scale maps
No full textThe assessment of class frequency in soil map legends is affected by uncertainty, especially at small scales where
generalization is greater. The aim of this study was to test the hypothesis that data mining techniques provide
better estimation of class frequency than traditional deterministic pedology in a national soil map.
In the 1:5,000,000 map of Italian soil regions, the soil classes are the WRB reference soil groups (RSGs). Different
data mining techniques, namely neural networks, randomforests, boosted tree, classification and regression tree,
and supported vector machine (SVM), were tested and the last one gave the best RSG predictions using selected
auxiliary variables and 22,015 classified soil profiles. The five most frequent RSGs resulting from the two
approaches were compared. The outcomes were validated with a Bayesian approach applied to a subset of 10%
of geographically representative profiles, which were kept out before data processing. The validation provided
the values of both positive and negative prediction abilities.
The most frequent classes were equally predicted by the two methods,which differed however from the forecast
of the other classes. The Bayesian validation indicated that the SVMmethod wasmore reliable than the deterministic
pedological approach and that both approaches were more confident in predicting the absence rather than
the presence of a soil type
USING WRB TO MAP THE SOIL SYSTEMS OF ITALY
Get PDFAim of this work was to test the 2010 version of the WRB soil classification for compilating a map
of the soil systems of Italy at 1:500,000 scale. The source of data was the national geodatabase
storing information on 1,414 Soil Typological Units (STUs). Though, basically, we followed WRB
criteria to prioritize soil qualifiers, however, it was necessary to work out an original methodology in
the map legend representation to reproduce the high variability inside each delineation meanwhile
avoiding any loss of information. Each map unit may represent a combination of three codominant
STUs at the most. Dominant STUs were assessed summing up the occurrence of STUs
in the Land Components (LCs) of every soil system, where each LC is a specific combination of
morphology, lithology and land cover. STUs were classified according to the WRB soil
classification system, at the third level, that is, reference soil group and first two qualifiers, when
possible. Since the large number of delineations, map units grouping was needed to make the map
more legible. Legend colours were organized according to soil regions groups firstly, then by
considering the highest level of soil classification, so resulting a nidificated legend. The map
showed 3,357 polygons and 704 map units. The most common STU were Calcaric Cambisols, by
far followed by Calcaric Regosols, Eutric Cambisols, Haplic Calcisols, Vertic Cambisols, Cutanic
Luvisols, Leptic Pheozems, Chromic Luvisols, Dystric Cambisols, Fluvic Cambisols, and others
STUs belonging to almost all the WRB soil references. Keywords: geodatabase, soil system
SOILS WITH HIGH ORGANIC CARBON STORAGE CAPACITY IN DEPTH
Get PDFMost studies about soil organic carbon (OC) stock focus on the topsoil storage capacity, however,
it has been proved that OC can reach relatively high values also in depth. The aim of this work was
a preliminary investigation of the soil types with a high OC content in depth and the relationship
with the main pedogenetic factors. The dataset was the 1,414 Italian National Soil Typologies
(STU). The selected attributes were: mean value of OC in the superficial functional horizon (L1);
weighted average value between 50 and 100 cm (L2) and under 100 cm (L3); WRB classification;
main lithology, morphology and land-use. About 92% of typologies had more than 0.58% of OC in
L1, about 30% in L2, and 10% in L3. The highest OC contents were in L2 of Histosols, Umbrisols,
Podzols, Vertisols, Andosols, and in L3 of Vertisols, Andosols, Fluvisols. STU on volcanic rocks,
slope and residual deposits showed relatively higher accumulation in L2; soils on delta plane,
lacustrine and alluvial deposits, both in L2 and L3. STU on upland plains, transitional areas with
plateau in the mountain, high gradient mountains and low plains, showed higher OC content.
Land-use was not significantly connected with OC content in depth. About 65% of the studied
territory (47% of Italian surface) had a relatively high CO content in L2, and about 2% in L3. The
main processes connected to soil CO storage capacity in depth were morphological, namely
colluvium and alluvium, as well as pedological, in particular, podzolization and andisolization
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
Comparing different approaches - data mining, geostatistic, and deterministic pedology - to assess the frequency of WRB Reference Soil Groups in the Italian soil regions
Get PDFEstimating frequency of soil classes in map unit is always affected by some degree of uncertainty, especially at
small scales, with a larger generalization.
The aim of this study was to compare different possible approaches - data mining, geostatistic, deterministic
pedology - to assess the frequency of WRB Reference Soil Groups (RSG) in the major Italian soil regions.
In the soil map of Italy (Costantini et al., 2012), a list of the first five RSG was reported in each major 10 soil
regions. The soil map was produced using the national soil geodatabase, which stored 22,015 analyzed and
classified pedons, 1,413 soil typological unit (STU) and a set of auxiliary variables (lithology, land-use, DEM).
Other variables were added, to better consider the influence of soil forming factors (slope, soil aridity index,
carbon stock, soil inorganic carbon content, clay, sand, geography of soil regions and soil systems) and a grid at 1
km mesh was set up.
The traditional deterministic pedology assessed the STU frequency according to the expert judgment presence in
every elementary landscape which formed the mapping unit.
Different data mining techniques were firstly compared in their ability to predict RSG through auxiliary variables
(neural networks, random forests, boosted tree, supported vector machine (SVM)). We selected SVM according
to the result of a testing set. A SVM model is a representation of the examples as points in space, mapped so that
examples of separate categories are divided by a clear gap that is as wide as possible.
The geostatistic algorithm we used was an indicator collocated cokriging. The class values of the auxiliary
variables, available at all the points of the grid, were transformed in indicator variables (values 0, 1). A principal
component analysis allowed us to select the variables that were able to explain the largest variability, and to
correlate each RSG with the first principal component, which explained the 51% of the total variability. The
principal component was used as collocated variable. The results were as many probability maps as the estimated
WRB classes. They were summed up in a unique map, with the most probable class at each pixel.
The first five more frequent RSG resulting from the three methods were compared.
The outcomes were validated with a subset of the 10% of the pedons, kept out before the elaborations. The error
estimate was produced for each estimated RSG.
The first results, obtained in one of the most widespread soil region (plains and low hills of central and southern
Italy) showed that the first two frequency classes were the same for all the three methods. The deterministic
method differed from the others at the third position, while the statistical methods inverted the third and fourth
position.
An advantage of the SVM was the possibility to use in the same elaboration numeric and categorical variable,
without any previous transformation, which reduced the processing time.
A Bayesian validation indicated that the SVM method was as reliable as the indicator collocated cokriging, and
better than the deterministic pedological approach
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
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