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1.
The standard theory of optimal jurisdictional size hinges on the existence of economies of scale in the provision of local public goods and services. However, despite its relevance for forced local amalgamation programs and related policies, the empirical evidence on the existence of such economies of scale remains elusive. The main goal of this paper is to produce an updated and comprehensive quantitative review of the existence of economies of scale in the provision of local public goods using a meta-analysis approach to systematize the wide range of empirical approaches and modeling frameworks found in the previous literature. Our analysis confirms the presence of moderately increasing to constant returns to scale in the provision of local services with no reduction in the average costs of production in the delivery of most local public services beyond a certain, modest jurisdictional size, which many studies have estimated at 10,000 residents. Also, the potential for economies of scale differs at least across three traditional services: education, water and sanitation, and garbage collection, being highest for education and lowest for garbage collection. Our analysis also offers guidelines for future empirical research in this area. Physical output and production cost data should be used, together with translog specifications for the modeling of cost functions. Last, we find evidence that the determinants of output cost elasticity include bidirectional publication bias and population density but do not include the presence or absence of modern “lean” production technologies or the (perceived) capital intensity of the sector, contrary to conventional wisdom. These findings have significant policy implications for countries considering jurisdictional consolidation programs.  相似文献   
2.
Shell beads are well established in the archaeological record of sub-Saharan Africa and appear as early as 75,000 BP; however, most research has focused on ostrich eggshell (OES) and various marine mollusc species. Beads made from various land snails shells (LSS), frequently described as Achatina, also appear to be widespread. Yet tracking their appearance and distribution is difficult because LSS beads are often intentionally or unintentionally lumped with OES beads, there are no directly dated examples, and bead reporting in general is highly variable in the archaeological literature. Nevertheless, Achatina and other potential cases of LSS beads are present at over 80 archaeological sites in at least eight countries, spanning the early Holocene to recent past. Here, we collate published cases and report on several more. We also present a new case from Magubike Rockshelter in southern Tanzania with the first directly dated LSS beads, which we use to illustrate methods for identifying LSS as a raw material. Despite the long history of OES bead production on the continent and the abundance of land snails available throughout the Pleistocene, LSS beads appear only in the late Holocene and are almost exclusively found in Iron Age contexts. We consider possible explanations for the late adoption of land snails as a raw material for beadmaking within the larger context of environmental, economic, and social processes in Holocene Africa. By highlighting the existence of these artifacts, we hope to facilitate more in-depth research on the timing, production, and distribution of LSS beads in African prehistory.  相似文献   
3.
Professor James Kwesi Anquandah was Ghana’s first archaeologist. He was also the first Ghanaian to become head of the Archaeology Department at the University of Ghana, which was the first archaeology department in sub-Saharan Africa, established in 1951. Dedicating his life to Ghanaian archaeology, particularly during the difficult years in Ghana in the 1980s and early 1990s, Anquandah had a significant impact on the development of archaeology in Ghana. In addition to his research, advisory and curatorial work, Professor Anquandah was instrumental in the training of three generations of Ghanaian archaeologists. During the course of a professional career that spanned nearly six decades, Professor Anquandah made archaeology relevant and accessible to all Ghanaians.  相似文献   
4.
The period comprising the end of the Early Neolithic and the Middle Neolithic, dated broadly within the fifth millennium cal BC, corresponds to an interval that remains largely unknown in the extreme north-western tip of Africa. This situation contrasts with that of the Early Neolithic, a period characterised by the earliest evidence of the diffusion of a productive economy, cultivated plants and domestic animals. The paucity of data for these later phases can be explained in part by the lack of secure contexts and sequences based on radiocarbon datings of short-lived samples. The current study presents the results of the excavations of El-Khil Caves B and C that yield materials allowing re-evaluation of the chronology of a type of ceramic known as Ashakar ware. The study also identifies two traditions in the northern Moroccan Middle Neolithic. The first is heir to the so-called Impressa Mediterranean ware and rooted in the Cardial Neolithic, while the second is characterised by roulette cord impressions, red slip and tunnel lugs and probably rooted in the region of the Sahara, and has no technological precedents in the study area.  相似文献   
5.
The study presents the results of neutron activation analysis (NAA) of contemporary pottery from Tigray Regional State, northern highland Ethiopia. This is the first regional-scale study of ceramic composition of Tigray’s pottery and is part of an ethnoarchaeological study of the material and social contexts of pottery production and consumption in Tigray’s Eastern (Misraqawi), Central (Mehakelegnaw), and North-western (Semien Mi’irabawi) zones. The analysis identifies clear compositional groups with strong regional patterns, an encouraging result for the use of NAA to study Tigray’s ancient pottery trade. Significantly, the study further contributes to discussions of how mutually constituted social identities of potters and consumers affect compositional patterning in the distribution of pottery in market networks.  相似文献   
6.
Four decades have passed since Harlan and Stemler (1976) proposed the eastern Sahelian zone as the most likely center of Sorghum bicolor domestication. Recently, new data on seed impressions on Butana Group pottery, from the fourth millennium BC in the southern Atbai region of the far eastern Sahelian Belt in Africa, show evidence for cultivation activities of sorghum displaying some domestication traits. Pennisetum glaucum may have been undergoing domestication shortly thereafter in the western Sahel, as finds of fully domesticated pearl millet are present in southeastern Mali by the second half of the third millennium BC, and present in eastern Sudan by the early second millennium BC. The dispersal of the latter to India took less than 1000 years according to present data. Here, we review the middle Holocene Sudanese archaeological data for the first time, to situate the origins and spread of these two native summer rainfall cereals in what is proposed to be their eastern Sahelian Sudan gateway to the Red Sea and the Indian Ocean trade.  相似文献   
7.
First visited by westerners in the mid-nineteenth century, Saharan rock art has since received a great deal of attention. The richness and diversity of this region is recognised by the inclusion on the UNESCO World Heritage list of three properties: Tassili-n-Ajjer in Algeria, Tadrart Acacus in Libya, and Ennedi in Chad. The situation in many North African countries now makes this vast region very difficult to access: safety in the field is not guaranteed and few research funds are available. Today, a new generation of African and foreign scientists has no access to rock art sites in the north of the continent and the lack of fieldwork may entail a lack of safeguard and awareness. The growth of digital technologies over the last 15 years has revolutionised methods for recording rock art sites. Digital technologies are also used to mitigate the gap between artworks and accessibility in those countries where turmoil and social instability make fieldwork impossible. However, much of the documentation and most digital recordings of artworks currently available on the Internet lack an archaeological context. Equally, many of these websites barely mention methodological and theoretical aspects. It is also difficult to understand the extent of awareness among local communities in remote areas—sometimes suffering a digital and linguistic divide—and if (and how) they are genuinely able to exploit these digital resources. Here, I collate some examples from different parts of the Sahara illustrating that the recording, management and dissemination of rock art still present highs and lows. I argue that we should share theories and methods within the digital scientific community, with a view to adopting a shared nomenclature and a public thesaurus, making our cataloguing criteria explicit and, finally, developing an ethical code of conduct involving local communities.  相似文献   
8.
9.
This article examines the political uses of classical architecture in the late eighteenth-century Polish-Lithuanian Commonwealth. It focuses specifically on the direct connection between the rise of the classical idiom on the eve of the collapse of the Commonwealth and the ill-fated idea of political recuperation of the deteriorating and dysfunctional state under the aegis of King Stanis?aw August Poniatowski (r. 1764–95). In particular, it outlines the extent and character of Polish-Lithuanian architectural classicism’s political engagement in the last decades of the eighteenth century. It also underscores the specific role of this architectural idiom as a political symbol and instrument of propaganda, which served to represent the idea of restoring political order to the Commonwealth and building a strong and self-sustaining political community headed by the king. Finally, it presents a selection of characteristic buildings and publications that contributed to this political discourse, and examines the ways classical architecture retained a political importance in the immediate aftermath of the destruction of the Polish-Lithuanian Commonwealth in 1795.  相似文献   
10.
Advanced data capture techniques, cost-effective data processing, and visualization technologies provide viable solutions for the documentation of archaeological heritage and material culture. Work at the UNESCO World Heritage site of Çatalhöyük has demonstrated that new digital approaches for capturing, processing, analyzing, and curating stratigraphic data in 3D are now feasible. Real-time visualization engines allow us to simulate the stratigraphy of a site, the three-dimensional surfaces of ancient buildings, as well as the ever-changing morphology of cultural landscapes. Nonetheless, more work needs to be done to address methodological questions such as follows: can three-dimensional models and stratigraphic relationships, based on 3D surfaces and volumes, be used to perform archaeological interpretation? How can a 3D virtual scenario become the interface to cultural data and metadata stored in external online databases? How can we foster a sense of presence and user embodiment in the simulation of ancient cities and archaeological sites? This article aims to provide viable solutions to the methodological challenge of designing a comprehensive digital archaeological workflow from the data acquisition and interpretation in the field to a three-dimensional digital data curation based on interactive visualization, searchable 3D data, and virtual environments. This work describes the results we achieved developing the application Dig@IT, a multi-platform, scalable virtual reality tool able to foster archaeological data analysis, interpretation, and curation in a realistic and highly interactive virtual environment.  相似文献   
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