88 research outputs found
Poziom zaufania i wiarygodność polskich studentów na tle międzynarodowym
This article presents the results of an experimental research carried out in Poland on selected aspects of social capital. These aspects were trust and trustworthiness. Our research was conducted on a total of 1540 students at universities in 16 Polish cities, capitals of 16 administrative regions, and was based on a commonly used experimental game termed the ‘Trust Game’. These results were compared with the results of studies performed in many other countries all over the world. It has been found that with regard to the proportion of money returned by Player B (a measure of trustworthiness), Poles (and more generally, those from Central and Eastern Europe) do not significantly differ from other countries belonging to Western culture (Oceania, Western Europe, North America). Based on the proportion of the money transferred by Player A (a measure of generalised trust), there is only a weak indication that Poles are less trusting than other Europeans.Artykuł prezentuje wyniki badań eksperymentalnych nad wybranymi aspektami kapitału społecznego w Polsce na tle innych państw. Analizowane są w nim aspekty: zaufania i wiarygodności. W artykule porównano wyniki badań opartych na typowej grę eksperymentalną (grę „zaufanie”), w tym polskie badania autorów przeprowadzone na grupie 1540 studentów w 16 miastach – stolicach regionów Polski. Wyniki badań wskazują, że względem proporcji pieniędzy oddanych przez gracza B (miara wiarygodności), Polacy (oraz ogólnie mieszkańcy Europy Centralnej/Wschodniej) nie różnią od osób z kultury zachodniej (Oceania, Europa Zachodnia, Ameryka Północna). Biorąc pod uwagę proporcję pieniędzy przekazanych przez gracza A (miara zaufania), istnieją słabe tylko dowody, że Polacy przekazują mniejszą część (czyli są mniej ufni) niż pozostali Europejczycy
Evidence of interpersonal violence or a special funeral rite in the Neolithic multiple burial from Koszyce in southern Poland : a forensic analysis
Combination of linear classifiers using score function -- analysis of possible combination strategies
In this work, we addressed the issue of combining linear classifiers using
their score functions. The value of the scoring function depends on the
distance from the decision boundary. Two score functions have been tested and
four different combination strategies were investigated. During the
experimental study, the proposed approach was applied to the heterogeneous
ensemble and it was compared to two reference methods -- majority voting and
model averaging respectively. The comparison was made in terms of seven
different quality criteria. The result shows that combination strategies based
on simple average, and trimmed average are the best combination strategies of
the geometrical combination
The magnetic survey of the early Scythian burial site and settlements in the Turan-Uyuk valley in Tuva
In 2019, Polish archaeologists took part in an expedition of the Hermitage Museum, led by K.V. Chugunov, in Chinge-Tey cemetery, Tuva (Russian Federation). This paper presents the result of magnetic surveys carried out within the so-called western chain of barrows and the around the princely barrow of Chinge-Tey I. This method of non-invasive research is very well suited to the landscape and has produced a significant body of information. Among others, the survey of the western chain identified a stone mantle in barrow 8, which makes it different from other barrows from this group, whose mounds were built of earth. Another important result is the identification of a stone circle surrounding a cult feature (certainly associated with eschatological rituals) known as the northern complex. The presence of the circle came as a surprise for the investigators of the site, as it does not manifest itself at all on the surface of the site. On the other hand, it is worth noting one negative result, which nevertheless allows for some conclusions, namely the lack of detectable anomalies connected with one of the tombs in the vicinity of Chinge-Tey I (barrow 15). Despite being clearly discernible in the landscape, and even more evident in LIDAR images, the barrow is invisible on images produced with a magnetometer. This means that one cannot rule out a possibility that other structures undetectable by magnetic surveys may be present within the investigated part of the cemetery. Nevertheless, one cannot but arrive at the conclusion that the results generated by the magnetic research provide significant information concerning the spatial arrangement of the cemetery and are helpful in planning archaeological excavation
Exit probability in a one-dimensional nonlinear q-voter model
We formulate and investigate the nonlinear -voter model (which as special
cases includes the linear voter and the Sznajd model) on a one dimensional
lattice. We derive analytical formula for the exit probability and show that it
agrees perfectly with Monte Carlo simulations. The puzzle, that we deal with
here, may be contained in a simple question: "Why the mean field approach gives
the exact formula for the exit probability in the one-dimensional nonlinear
-voter model?". To answer this question we test several hypothesis proposed
recently for the Sznajd model, including the finite size effects, the influence
of the range of interactions and the importance of the initial step of the
evolution. On the one hand, our work is part of a trend of the current debate
on the form of the exit probability in the one-dimensional Sznajd model but on
the other hand, it concerns the much broader problem of nonlinear -voter
model
Some new results on one-dimensional outflow dynamics
In this paper we introduce modified version of one-dimensional outflow
dynamics (known as a Sznajd model) which simplifies the analytical treatment.
We show that simulations results of the original and modified rules are exactly
the same for various initial conditions. We obtain the analytical formula for
exit probability using Kirkwood approximation and we show that it agrees
perfectly with computer simulations in case of random initial conditions.
Moreover, we compare our results with earlier analytical calculations obtained
from renormalization group and from general sequential probabilistic frame
introduced by Galam. Using computer simulations we investigate the time
evolution of several correlation functions to show if Kirkwood approximation
can be justified. Surprisingly, it occurs that Kirkwood approximation gives
correct results even for these initial conditions for which it cannot be easily
justified.Comment: 6 pages, 7 figure
The absolute chronology of collective burials from the 2nd Millennium BC in East Central Europe
This article discusses the absolute chronology of collective burials of the Trzciniec Cultural Circle
communities of the Middle Bronze Age in East Central Europe. Based on Bayesian modeling of 91 accelerator mass spectrometry radiocarbon (AMS 14C) dates from 18 cemeteries, the practice of collective burying of individuals was linked to a period of 400-640 (95.4%) years, between 1830–1690 (95.4%) and 1320-1160 (95.4%) BC. Collective burials in mounds with both cremation and inhumation rites were found earliest in the upland zone regardless of grave structure type (mounded or flat). Bayesian modeling of 14C determinations suggests that this practice was being transmitted generally from the southeast to the northwest direction. Bayesian modeling of the dates from the largest cemetery in Z· erniki Górne, Lesser Poland Upland, confirmed the duration of use of the necropolis as ca. 140–310 (95.4%) years. Further results show the partial contemporaneity of burials and allow formulation of a spatial and temporal development model of the necropolis. Based on the investigation, some graves were used over just a couple of years and others over nearly 200, with up to 30 individuals found in a single grave
Machine learning algorithms for systematic review: reducing workload in a preclinical review of animal studies and reducing human screening error
BACKGROUND: Here, we outline a method of applying existing machine learning (ML) approaches to aid citation screening in an on-going broad and shallow systematic review of preclinical animal studies. The aim is to achieve a high-performing algorithm comparable to human screening that can reduce human resources required for carrying out this step of a systematic review. METHODS: We applied ML approaches to a broad systematic review of animal models of depression at the citation screening stage. We tested two independently developed ML approaches which used different classification models and feature sets. We recorded the performance of the ML approaches on an unseen validation set of papers using sensitivity, specificity and accuracy. We aimed to achieve 95% sensitivity and to maximise specificity. The classification model providing the most accurate predictions was applied to the remaining unseen records in the dataset and will be used in the next stage of the preclinical biomedical sciences systematic review. We used a cross-validation technique to assign ML inclusion likelihood scores to the human screened records, to identify potential errors made during the human screening process (error analysis). RESULTS: ML approaches reached 98.7% sensitivity based on learning from a training set of 5749 records, with an inclusion prevalence of 13.2%. The highest level of specificity reached was 86%. Performance was assessed on an independent validation dataset. Human errors in the training and validation sets were successfully identified using the assigned inclusion likelihood from the ML model to highlight discrepancies. Training the ML algorithm on the corrected dataset improved the specificity of the algorithm without compromising sensitivity. Error analysis correction leads to a 3% improvement in sensitivity and specificity, which increases precision and accuracy of the ML algorithm. CONCLUSIONS: This work has confirmed the performance and application of ML algorithms for screening in systematic reviews of preclinical animal studies. It has highlighted the novel use of ML algorithms to identify human error. This needs to be confirmed in other reviews with different inclusion prevalence levels, but represents a promising approach to integrating human decisions and automation in systematic review methodology
Unraveling ancestry, kinship, and violence in a Late Neolithic mass grave
The third millennium BCE was a period of major cultural and demographic changes in Europe that signaled the beginning of the Bronze Age. People from the Pontic steppe expanded westward, leading to the formation of the Corded Ware complex and transforming the genetic landscape of Europe. At the time, the Globular Amphora culture (3300–2700 BCE) existed over large parts of Central and Eastern Europe, but little is known about their interaction with neighboring Corded Ware groups and steppe societies. Here we present a detailed study of a Late Neolithic mass grave from southern Poland belonging to the Globular Amphora culture and containing the remains of 15 men, women, and children, all killed by blows to the head. We sequenced their genomes to between 1.1- and 3.9-fold coverage and performed kinship analyses that demonstrate that the individuals belonged to a large extended family. The bodies had been carefully laid out according to kin relationships by someone who evidently knew the deceased. From a population genetic viewpoint, the people from Koszyce are clearly distinct from neighboring Corded Ware groups because of their lack of steppe-related ancestry. Although the reason for the massacre is unknown, it is possible that it was connected with the expansion of Corded Ware groups, which may have resulted in competition for resources and violent conflict. Together with the archaeological evidence, these analyses provide an unprecedented level of insight into the kinship structure and social behavior of a Late Neolithic community
Population genomics of post-glacial western Eurasia.
Western Eurasia witnessed several large-scale human migrations during the Holocene <sup>1-5</sup> . Here, to investigate the cross-continental effects of these migrations, we shotgun-sequenced 317 genomes-mainly from the Mesolithic and Neolithic periods-from across northern and western Eurasia. These were imputed alongside published data to obtain diploid genotypes from more than 1,600 ancient humans. Our analyses revealed a 'great divide' genomic boundary extending from the Black Sea to the Baltic. Mesolithic hunter-gatherers were highly genetically differentiated east and west of this zone, and the effect of the neolithization was equally disparate. Large-scale ancestry shifts occurred in the west as farming was introduced, including near-total replacement of hunter-gatherers in many areas, whereas no substantial ancestry shifts happened east of the zone during the same period. Similarly, relatedness decreased in the west from the Neolithic transition onwards, whereas, east of the Urals, relatedness remained high until around 4,000 BP, consistent with the persistence of localized groups of hunter-gatherers. The boundary dissolved when Yamnaya-related ancestry spread across western Eurasia around 5,000 BP, resulting in a second major turnover that reached most parts of Europe within a 1,000-year span. The genetic origin and fate of the Yamnaya have remained elusive, but we show that hunter-gatherers from the Middle Don region contributed ancestry to them. Yamnaya groups later admixed with individuals associated with the Globular Amphora culture before expanding into Europe. Similar turnovers occurred in western Siberia, where we report new genomic data from a 'Neolithic steppe' cline spanning the Siberian forest steppe to Lake Baikal. These prehistoric migrations had profound and lasting effects on the genetic diversity of Eurasian populations
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