Some Extensions of Mills's Method for Urban Population Density Gradient Estimation

This paper extends Milk's method for estimating urban population density gradients to general noncircular and asymmetrical urban forms, using Gauss-Legendre quadrature embedded in a Newton-Raphson root finding algorithm. We also examine the sensitivity of the Mills method to measurement errors in the assumptions. Several issues arising from the comparison of analytical, Mills type estimation procedures with statistical procedures are explored, particularly in light of recent work that questions the negative exponential formulation of urban density gradients. We note in particular the influence of secondary population centers as a source of estimation bias.     

A Mathematical Model of the Density Distribution of Moscow's Population

A student research project at Moscow University tests Colin Clark's formula for the distribution of the density of a single-center city by applying it to population data of Moscow for 1963, 1964, and 1965. The students obtain repression lines and equations for the population density of Moscow and draw the density field by means of isolines. The results suggest population movement from the central district to outlying areas where intensive housing construction is under way.     

A Structural Approach to the Form of the Population Density Function

The central objective of this paper is to explore a comprehensive structural modeling approach that extracts analytical density functions answering questions raised by recent empirical studies.     

The Density of Population of a City and the Density of Probability of a Random Magnitude

A continuation of a paper translated in Soviet Geography, April 1966, establishes a systematic relationship between the concept of a city's population density and the general theoretical probability concept of the probability density function of a two-dimensional random magnitude, and extends the discussion of population-density models beyond the category of single-center cities to a variety of non-single-center formations.     

Association between Population Density and The Market Areas of Towns

This paper examines the relationship between population density and town spacing in four kinds of environment. These are: (1) linear curves of demand, transport and production costs and an even population distribution; (2) nonlinear transport cost curves over space; (3) variable population density within hinterlands; and (4) variation of transport costs with population density. Previously, it has been shown that the criterion of free entry does not uniquely determine town spacing. The implications of four stronger criteria are therefore examined in this paper. These location criteria are: (a) the number of towns is maximized; (b) the number of towns in minimized, subject to all consumers' being served; (c) the towns are all owned by one profit-maximizing monopolist; and (d) the average of some consumer utility function is maximized. In cases (a), (c), and (d) spacing decreases with density; in (b) spacing is an increasing function of density. Actual data are presented on the spacing of towns in Iowa and shopping centers in Chicago which indicate that spacing and population density are not associated. These results are consistent with the notion that entry is free but are not consistent with the stronger constraints employed in this paper.     

Uniform Probability Density Analysis and Population History in the Northern Rio Grande

One of the basic challenges facing archaeology is translating surface evidence into population estimates with sufficient chronological resolution for demographic analysis. The problem is especially acute when one is working with sites inhabited across multiple chronological periods and the production curves for pottery types are unknown. In this paper, I present a Bayesian statistical method which I call uniform probability density analysis that is tailored to this situation. This method combines uniform distributions derived from the local pottery chronology with pottery assemblage data to reconstruct the population history of individual settlements. I also illustrate applications of this method at the site and regional level using data from Cuyamungue and the surrounding Tewa Basin/VEP II New Mexico project area. The results allow one to identify a period of significant population movement corresponding to the period of Tewa ethnogenesis in the thirteenth century CE.     

Reconstructing Population Density Surfaces from Areal Data: A Comparison of Tobler's Pycnophylactic Interpolation Method and Area-to-Point Kriging

We compare Tobler's pycnophylactic interpolation method with the geostatistical approach of area-to-point kriging for distributing population data collected by areal unit in 18 census tracts in Ann Arbor for 1970 to reconstruct a population density surface. In both methods, (1) the areal data are reproduced when the predicted population density is upscaled; (2) physical boundary conditions are accounted for, if they exist; and (3) inequality constraints, such as the requirement of non-negative point predictions, are satisfied. The results show that when a certain variogram model, that is, the de Wijsian model corresponding to the free-space Green's function of Laplace's equation, is used in the geostatistical approach under the same boundary condition and constraints with Tobler's approach, the predicted population density surfaces are almost identical (up to numerical errors and discretization discrepancies). The implications of these findings are twofold: (1) multiple attribute surfaces can be constructed from areal data using the geostatistical approach, depending on the particular point variogram model adopted—that variogram model need not be the one associated with Tobler's solution and (2) it is the analyst's responsibility to justify whether the smoothness criterion employed in Tobler's approach is relevant to the particular application at hand. A notable advantage of the geostatistical approach over Tobler's is that it allows reporting the uncertainty or reliability of the interpolated values, with critical implications for uncertainty propagation in spatial analysis operations.     

A Generalization of the Utility Theory Approach To the Problem of Spatial Interaction

The derivation of the gravity model from utility theory is reformulated and generalized in order to show (1) how both the number of trips to individual destinations and the total travel budget may be determined simultaneously, and (2) how the effect of both distance and destination quality on trip distribution and total budget may be analyzed. Results are compared with the revealed space preference approach and are found to be superior in dealing theoretically with trip frequency and the effects of spatial context. For empirical applications, however, the revealed preference approach is advantageous.     

高句丽人口问题研究

本文对高句丽人口数量的发展演变和丧失王统后的高句丽人口流向问题进行了分析考察 ,认为其人口初创时不多 ,三国曹魏时明确记载是 3万户 ,南北朝时为 9万户 ,盛唐之际则达 6 9 7万户。其人口在持续增长中 ,加入了汉、扶余、沃沮、秽貊、百济、等各部族或民族的众多人口。当高氏王统丧失后 ,人口渐次迁移 ,流入中原和东北的渤海、突厥、新罗等政权的辖区中。     

墨子国家观浅议

墨子的国家观是其政治思想的集中体现,是其兼爱价值观在政治上的反映,也是其义利观的表现。本文从墨子关于国家职能和国家管理机构的设置、国家管理者之间的关系入手,探讨了墨子关于国家观的基本主张。墨子的国家观虽然带有空想色彩．但其首创性启迪了后代思想家．他提出的“尚贤”和“君民通约”的观点对后世争取平民权利有着重要指导意义。