HLO1‐south: An Early Neolithic site in Wadi al‐Hilo (Sharjah,UAE)

Site HLO1 (Sharjah, UAE), situated in a particularly favourable geographical position, has provided an extraordinary range of anthropogenic radiocarbon dates, spanning before 8000 to Zero BCE. The Neolithic is represented by finds from the eighth to the fifth millennium BCE. Apart from the dated fireplaces, however, there are almost no typical artefacts of this period. Small stone structures appear to have been early Neolithic graves. A middle Neolithic grave consisted of a large rounded stone heap which was reused as a grave during the Late Bronze Age. The site is interpreted as a campsite of nomadic herders, used throughout the Neolithic period. After a break in the fourth millennium BCE, the site became a Bronze Age smelting site which continued to be settled until the Late Iron Age.     

Efficient but destructive: a test of the dental wash technique using secondary electron microscopy

The Boyadjian et al dental wash technique provides, in certain contexts, the only chance to analyze and quantify the use of plants by past populations and is therefore an important milestone for the reconstruction of paleodiet. With this paper we present recent investigations and results upon the influence of this method on teeth. A series of six teeth from a three thousand years old Brazilian shellmound (Jabuticabeira II) was examined before and after dental wash. The main focus was documenting the alteration of the surfaces and microstructures. The status of all teeth were documented using macrophotography, optical light microscopy, and atmospheric Secondary Electron Microscopy (aSEM) prior and after applying the dental wash technique. The comparison of pictures taken before and after dental wash showed the different degrees of variation and damage done to the teeth but, also, provided additional information about microstructures, which have not been visible before. Consequently we suggest that dental wash should only be carried out, if absolutely necessary, after dental pathology, dental morphology and microwear studies have been accomplished.     

A Spatial Autoregressive Poisson Gravity Model

In this article, a Poisson gravity model is introduced that incorporates spatial dependence of the explained variable without relying on restrictive distributional assumptions of the underlying data‐generating process. The model comprises a spatially filtered component—including the origin‐, destination‐, and origin‐destination‐specific variables—and a spatial residual variable that captures origin‐ and destination‐based spatial autocorrelation. We derive a two‐stage nonlinear least‐squares (NLS) estimator (2NLS) that is hetero‐scedasticity‐robust and, thus, controls for the problem of over‐ or underdispersion that often is present in the empirical analysis of discrete data or, in the case of overdispersion, if spatial autocorrelation is present. This estimator can be shown to have desirable properties for different distributional assumptions, like the observed flows or (spatially) filtered component being either Poisson or negative binomial. In our spatial autoregressive (SAR) model specification, the resulting parameter estimates can be interpreted as the implied total impact effects defined as the sum of direct and indirect spatial feedback effects. Monte Carlo results indicate marginal finite sample biases in the mean and standard deviation of the parameter estimates and convergence to the true parameter values as the sample size increases. In addition, this article illustrates the model by analyzing patent citation flows data across European regions. En el presente artículo, se introduce un modelo de gravedad Poisson, que incorpora la dependencia espacial de la variable explicada, sin apoyarse en presunciones de distribución restrictivas del proceso subyacente de generación de datos. El modelo comprende de un componente espacialmente filtrado, que incluye las variables de origen, destino y origen‐destino específico; y una variable espacial residual que captura la auto‐correlación espacial basada en el origen y destino. Se deriva del calculador (2NLS) de dos etapas no lineales de mínimos cuadrados (NLS), el cual es robusto en heterocedasticidad, y por ello controla el problema de sobre‐dispersión o baja‐dispersión (over and under dispersion), que a menudo se presenta en el análisis empírico de datos discretos; o, en el caso de de sobre‐dispersión, cuando se presenta la auto correlación espacial. Este calculador puede demostrar tener propiedades deseables para diferentes supuestos distribucionales, como los flujos observados un componente (espacialmente) filtrado, ya sea Poisson o binomial negativo. En nuestra especificación de modelo espacial auto regresivo (SAR), las estimaciones de los parámetros resultantes se pueden interpretar como los efectos de impacto total implícitos, definidos como la suma de efectos espaciales, directos o indirectos, de retroalimentación (feedback). Los resultados Monte Carlo indican sesgos marginales de muestras finitas en la media y la desviación estándar de los parámetros estimados, y la convergencia de los valores de los parámetros reales, a medida que aumenta el tamaño de muestra. Este artículo ilustra el modelo mediante el análisis de flujos de datos de citas de patentes, a través de las regiones europeas. 本文提出了一种蕴含空间依赖的泊松引力模型,该模型中解释变量无需依赖潜在数据生成过程的限制性分布假设。该模型由包含起点、终点、起点‐终点特定变量的空间滤波组分和空间残差变量组成,能捕捉到基于起点和终点的空间自相关。我们推导出一个二阶非线性最小二乘（NLS）估计（2NLS）,它对异方差具有鲁棒性,从而可控制对于离散或过离散数据经验性分析中经常出现的过离散和低离散问题。如果空间自相关存在,过离散数据分析就是一个例子。对于不同的分布假设,如或泊松分布或是负二项式分布的观测流或（空间）滤波组分,该估计量显示出令人满意的性能。在本文的空间自回归（SAR）模型设定中,参数估计结果可解释为隐含的全局影响效应,并可被定义为直接和间接的空间反馈效应之和。蒙特卡罗结果给出了参数估计中均值、标准差的临界有限样本偏差,且随样本量增大收敛于真正参数值。此外,本文基于欧洲地区专利引用的流数据进行了模型验证。     

The Asiatic marbles of the Hadrian's Villa at Tivoli

Multi-method provenance studies, including petrographic, isotopic, electron paramagnetic resonance and trace chemical analyses, have been carried out on 20 white, 9 black and 1 red artifacts purposely selected to investigate the use and distribution of sculptural marbles at the Hadrian's Villa. A large fraction of the marbles tested (21 samples, 70%) are shown to be from Asia Minor, mostly originating from the recently discovered site of Göktepe near Aphrodisias (15 or 71%). All the 9 black samples investigated and 6 out of 11 white Asiatic marbles are from Göktepe, the remaining being Docimium marble from Iscehisar (4 samples) and Aphrodisias marble from the city quarries (1 sample). The single red sculpture tested proved to be Carian red marble from the Iasos quarries, whereas non-Asiatic marbles include 3 Carrara and 6 Pentelicon samples. The selection of marbles tested is preliminary and incomplete, but, despite this, the results are noteworthy, especially since the marble of other sculptures from the Villa has already been identified as Göktepe. Together with other published results, the marble distribution at the Hadrian's Villa seems to suggest that the use of sculptural marbles in the Roman world underwent considerable changes around the turn of the 1st and the 2nd century AD. The evidence supporting this hypothesis is briefly summarized in the conclusions.     

Wachstum der Wissenschaftsressourcen in Deutschland 1650‐2000: Eine empirische Studie zur Anzahl der Hochschulen und Professoren sowie der Forschungsausgaben

When Derek J. de Solla Price studied the growth of science in the 1960s he found a very rapid exponential growth doubling every 15 years. He predicted a logistic slowing down of the growth rate until finally saturation is reached. This study examines three ressource indicators ‐ R&D expenditures, number of professors and of universities ‐ for Germany between 1650 and 2000. They show rather hyperbolic than exponential growth until 1980 when saturation is suddenly reached.