Homogeneous Neighborhoods Research Articles

Structure-adaptive image filtering using order statistics

In this article a structure-adaptive approach to the evaluation of image local properties for adaptive filtering is described. The adaptive procedure is based on selection of the most homogeneous neighborhood region from several possible structuring regions by the principle of maximum posterior probability. Then, an optimal evaluation of the pixel value at this point is performed involving pixels from the determined neighborhood region and the symmetric structuring region. The trimmed mean filters are used for the robust evaluation of local properties during estimation of object and background intensities when the supposed additive noise has a mixed conditional distribution, e.g., normal distribution with outliers. A time-efficient scheme for fast implementation of this method is proposed as well.

The Comrades' Belief: Intended and Unintended Consequences of Communism for Neighbourhood Relations in the Former GDR

Marxist societies were experiments not only in destratification but also in openness and cohesion. Of all relationships a political regime might use to create 'friendship between classes: those among neighbours may be most prone to manipulation. We examine how relationships among neighbours in the former GDR were affected by the regime's housing policy of mixing people of different classes. Our retrospective data were collected in May 1992 (n = 189) and in April 1993 (n = 300) among two random samples of respondents in Leipzig and Dresden. While the communist regime was very successful at creating neighbourhoods of mixed social composition, its housing policy failed to create friendship between classes. Meeting did not lead to mating: next-door neighbours were socially distinct and hardly socialized with each other. The few existing ties in the neighbourhood were largely restricted to similar others. We understand these shallow and homogeneous neighbourhood networks as the unintended effect of the party's political control of private life: one would be unlikely to invest in relations that posed a threat and with individuals one did not trust, such as neighbours, who were dissimilar to oneself and who, because they lived next-door, knew about one's private life as well. Analysis shows furthermore that being a neighbour and having a dissimilar occupation increases the chance of being distrusted.

Planning doctrine and post-industrial urban development: the Amsterdam experience

Urban planners have to develop a planning doctrine (Faludi and Van der Valk 1990). This concept stands for a body of thoughts concerning (a) spatial arrangements within an area, (b) the development of that area; and (c) the way both should be handled. To be successful, they need a planning community (planners, top officials and sub-national establishments for political support) that nurtures it. The planners of the Amsterdam General Extension Plan (1935) developed a doctrine that covers three levels of functions and activities: (1) Amsterdam is a regional centre, a closed functional system, an orthogenetic city. (2) a monocentric urban form and (3) homogeneous neighbourhood communities around a common neighbourhood centre (church, school, medical services, shops). Since the early 1970s Amsterdam has become (1) an international centre, a heterogenetic city, part of a network city system, (2) has developed into a polycentric urban region, and (3) has been acquiring ethnically mixed quarters, divided communities losing their basic function as common neighbourhood centres and even as ‘control areas’ or ‘domains’ (Hagerstrand 1970). So in Amsterdam the planning-doctrine was not particularly successful.

The residential preferences of blacks and whites: A four‐metropolis analysis

Three hypotheses seek to explain the persistence of residential segregation between blacks and whites in the United States: economic differentials, discrimination in housing and lending markets, and neighborhood preferences. The preferences hypothesis posits that both races wish to live in racially homogeneous neighborhoods. This article examines the preferences hypothesis by using recent interview data from metropolitan Atlanta, Boston, Detroit, and Los Angeles. Race continues to be significant in the residential decision‐making process. Whites’ willingness to move into a neighborhood is inversely related to the density of blacks living there. Blacks prefer integrated neighborhoods, but ones with a substantial representation of blacks. Preferences differ significantly from one metropolis to another, with Detroit representing the extreme. In the other three metropolises, the preferences of blacks and whites do overlap sufficiently to offer hope for a decline in segregation, provided that the influence of other forces, particularly discrimination, also declines.

The Directional Neighborhoods Approach to Contextual Classification of Images from Noisy Data

Abstract The directional neighborhoods approach (DNA) to classifying pixels and reconstructing images from remotely sensed noisy data is a newly proposed computer-intensive procedure that is partly Bayesian and partly data analytic. It uses the observational data to select an optimal, generally asymmetric, but relatively homogeneous neighborhood for contextually classifying pixels. A criterion for “homogeneity of neighborhood” is developed. DNA involves two stages: a zero-neighbor preclassification stage, followed by selection of the most homogeneous neighborhood, and then a final classification. We provide Monte Carlo simulations for a two-population image and compare DNA results with those from a reference Bayesian contextual classification. We show that DNA improves substantially on the reference classification procedure.

The Directional Neighborhoods Approach to Contextual Classification of Images From Noisy Data

Abstract The directional neighborhoods approach (DNA) to classifying pixels and reconstructing images from remotely sensed noisy data is a newly proposed computer-intensive procedure that is partly Bayesian and partly data analytic. It uses the observational data to select an optimal, generally asymmetric, but relatively homogeneous neighborhood for contextually classifying pixels. A criterion for “homogeneity of neighborhood” is developed. DNA involves two stages: a zero-neighbor preclassification stage, followed by selection of the most homogeneous neighborhood, and then a final classification. We provide Monte Carlo simulations for a two-population image and compare DNA results with those from a reference Bayesian contextual classification. We show that DNA improves substantially on the reference classification procedure.

How Much does Sorting Increase Inequality?

Some commentators argue that increased sorting into internally homogeneous neighborhoods, schools, and marriages is radically polarizing society. Calibration of a formal model, however, suggests that the steady-state standard deviation of education would increase only 1.7 percent if the correlation between neighbors' education doubled, and would fall only 1.6 percent if educational sorting by neighborhood disappeared. The steady-state standard deviation of education would grow 1 percent if the correlation between spouses' education increased from 0.6 to 0.8. In fact, marital and neighborhood sorting have been stable, or even decreasing historically. Sorting has somewhat more significant effects on intergenerational mobility than on inequality.

A "Commonplace" Conversation with Lani Guinier

Funderburg: What do you hope to remedy with Commonplace, your recently established, not-for-profit group? Guinier: Accomplish would be a better word; remedy sounds much too ambitious for the shoestring operation that we are presently. Perhaps in a year we might feel emboldened to discuss what we're remedying. But at this stage, we are struggling to transform public discourse, particularly about issues of race. We're proceeding along several different axes at once. The first one is an academic research agenda where we are trying to develop a methodology for structured dialogue, for multiracial deliberation, for collective decision-making and collaboration among people of diverse backgrounds and perspectives. We're designing focus groups to study competing hypotheses about the barriers to candid or honest public communication - particularly on race. And we're testing two major theses. One is that you have to get people together to talk about race by providing them a mutual task that doesn't have an explicit racial text. The second hypothesis we're testing is that you have to confront, magnify, and explode stereotypes before you can get people to the point of trust and intimacy. We then want to apply that methodology to public conversations that involve people in the media, public policy activists, to structure conversations - again across difference, not just of race or of gender, but of perspective and discipline - so that the journalists can learn how to see nuance and the academics can learn how to be more clear. In this take-it-on-the-road part of the project, we could actually try to intervene in local communities that are confronting conflict or - and this is where we're more inclined to intervene - we could try to change the way the media covers the issue of race, because the media plays such an important role as the connective tissue in our national and local community. Funderburg: Why does public discourse need to be restructured? Guinier: We are operating from the premise - and it is not an original premise [laughs] - that there is a breakdown in our ability to talk to each other on a number of issues. Unfortunately, political discourse resembles, to a great degree, the worst excess of the adversary model of litigation, the winner take model of sports, and the only one of you is going to be left standing model of war. When we use that structure to talk about something like race, it reinforces all the divisions and polarities we are experiencing on so many other levels, in terms of segregated housing patterns, people not going to school together or not watching the same television shows - basically, the prediction of the Kerner Commission from almost thirty years ago that we are becoming two nations, one white and one black. Even though it's a more heterogeneous nation in some ways, it is still very segregated. Funderburg: How is it more heterogeneous? Guinier: Number one, we can't just talk about race in a context of black and white. We have to think about other people of color in a global sense and the relationship not just between whites and people of color, but among and within communities of color. Second, there has been some progress: There is at least the appearance of increased diversity - on college campuses, in public legislatures and city councils and school boards, and on television - in what we see as representational icons. On the other hand, much of that is superficial; it's cosmetic, and it's temporary. People may work in a multiracial environment, but then go home to a very homogeneous neighborhood. Funderburg: Also, it seems that many multiracial environments are still tiered hierarchically. A company with a history of having white employees can say it's become diverse, but what positions are held by those people who bring the diversity? Guinier: Michael Lind recently wrote a terrific article in Harper's on the haves and the have-nots. …

Housing Credit Lending and Housing Markets

In this article, factor analyses are used to identify homogeneous neighborhoods, and canonical analyses are used to examine the relationships between neighborhoods and credit lending in the Cleveland, Ohio, area. The results reveal that variations in the supply and demand for loans are best explained by declining employment opportunities and demographic changes. The canonical analyses strongly indicate that the supply and demand for loans vacillate as a consequence of job insecurities, the decline in earnings capacity of less skilled workers, and long-term population and household declines. Further, the recessions and boom period of the 1980s differentially affected suburban mortgage submarkets.

Land ownership as a determinant in the formation of residential areas in Arab localities

This article examines the implications and significance of land ownership trends, on shaping the spatial residential landscape in Arab localities in Israel. Residential areas in Arab localities were characterised by ethnic-group or clan separation. Each clan or group resided in an homogeneous neighborhood, which, when compared to contiguous spatial residential areas, became heterogeneous. This phenomenon was preserved due to considerations of residential location relating to the land ownership pattern. A change in the land ownership pattern created neighboring, heterogeneous, ethnic residential spaces albeit homogeneous in origin or status. The article is based on literature and research published on the issue, as well as on interviews with land owners, planners and policy makers in three localities: Kafar Kana, She'faram and Um-AlFahm. Land ownership in all three localities was mapped in an outline plan and an affiliative map of households, according to principal clan or ethnic group, including migrant households identified in these localities. An analysis of and a comparison between the map of land ownership and that of affiliative households were also carried out. The research areas, selected to represent Arab localities, were described from aspects of geographic environment, size of population, ethnic composition and municipal development. This was followed by a review of the development of the land ownership pattern in Arab localities, based on the Ottoman Land Act of 1858. The built-up rural expanse was also examined as was the city-scape. The article defines the development of four landless groups who contributed to the shift in the traditional residential distribution pattern. These groups were demanding residential land in their localities and wherever land was available they purchased it and built their homes. Concurrently, the article relates to the various sources of land for residential building. It attempts to summarize the implications of the demand for land compared with its supply, by drafting a schematic model which will conclude the changing trends in residential development in Arab localities.

The Effect of Commitment on Adoption and Diffusion of Grass Cycling

Using a design that also permitted an assessment of the extent to which any increase in grass-cycling behavior diffused to the neighbors of treated participants, two types of commitment strategies for promoting residential grass cycling (i.e., not bagging grass clippings) were investigated. Baseline data were collected over a period of 4 weeks to determine which residents in each of three homogeneous neighborhoods bagged grass clippings for curbside pickup. A total of 558 houses observed to bag grass clippings during this period were included as participants in the experiment. Following baseline, the neighborhoods were randomly assigned to one of three conditions. Results indicated that participants who made a commitment to grass cycle and to talk to their neighbors had grass bags present significantly less often than either the commitment-only or control participants. This effect was present during the 4-week intervention period and also was sustained during an immediate 4-week follow-up period and a delayed 4-week follow-up period 12 months later. There also was a diffusion effect in which the neighbors of targeted participants showed significantly more grass cycling than controls, and this effect continued to increase through the 1-year follow-up measure. On the other hand, neither commitment-only participants nor their neighbors differed from controls during any period of the experiment.

A theory of persistent income inequality

This paper explores the dynamics of income inequality by studying the evolution of human capital investment and neighborhood choice for a population of families. Parents affect the conditional probability distribution of their children's income through the choice of a neighborhood in which to live. Neighborhood location affects children both through local public finance of education as well as through sociological effects. These forces combine to create incentives for wealthier families to segregate themselves into economically homogeneous neighborhoods. Economic stratification combines with strong neighborhoodwide feedback effects to transmit economic status across generations, leading to persistent income inequality.

The Revolt Against Cultural Determinism and the Meaning of Community Action: A View from Cincinnati

Since the 1920s, the discourse about American urban culture has suggested the appropriateness of organizing metropolitan life around territorial subcommunities in two distinctive ways, each of which yielded a distinctive period in the history of professional city and social welfare planning. During the first period, which persisted into the 1950s, the planners focused on the problem of forging a coherent sense of metropolitan community among cultural groups conceived of as separate but equal (or potentially equal). To achieve this goal, they emphasized the role of experts in analyzing the forces controlling urban culture and in devising schemes to segregate, assure the integrity of, and foster mutual understanding and respect among cultural groups whose characteristics stemmed from forces beyond the control of experts or group members. During the second period, which began in the 1950s and persists in our own time, planners abandoned cultural group determinism and the quest for a segregated yet coherent metropolitan community of separate but equal groups in homogeneous neighborhoods. Instead they decided they could control the future of the metropolis by persuading individuals to create heterogeneous neighborhoods through a process of “community action” in which neighborhood residents would define their culture (“lifestyles”) by participating in the design of the social and physical environment of the neighborhood of their choice. This new pattern of thinking about urban culture, which centered on “individualism” and neighborhood rather than groups and metropolitan community, involved a revolt against cultural group determinism, the notion that individuals carry an identity determined by the accident of their membership in the group with characteristics determined by the experience of a group in a social and physical environment created by “outsiders” and or impersonal “forces.”

New automatic techniques for smoothing and segmenting SAR images

A new algorithm for smoothing synthetic aperture radar (SAR) images, which is based on the estimation of the most homogeneous neighbourhood around each image pixel, is presented. The algorithm preserves fine details while removing noise along edges as well as in flat areas. An edge detection technique, based on the smoothing algorithm is also presented. Both the smoothing and the edge detection algorithms are implemented in the spatial domain, and without the need to use a threshold value. The performances of the algorithms are compared (qualitatively and quantitatively) with several standard techniques, using real and simulated images.

Gender, Class, and Space

The social area analyses and factorial ecologies of the 1950s and 1960s have constrained the way in which scholars conceptualize urban space; in particular, one can trace contemporary arguments regarding the social reproduction of class to the notion of homogeneous neighborhoods that emerges from social area analyses and factorial ecology. It is argued that the growth in female labor-force participation, the fact of occupational sex segregation, and other recent demographic trends have important implications for the social geography of the North American city. With 1980 Census data from the Worcester, MA Standard Metropolitan Statistical Area, the impact of the gender division of labor on urban social space is described; in particular it is shown that occupational segregation is an important source of intraneighborhood class heterogeneity. The final section of the paper is an exploration of the implications of the findings for theories of social reproduction and for class-based urban politics.

Taking Apart the American Dream: The Influence of Income and Family Composition on Residential Evaluations

Americans' overwhelming desires for single family homeownership have been so well documented that they have been termed the 'American Dream'. Government and financial incentives for homeownership are believed to allow the fulfillment of uniformly accepted housing norms which drive people to buy their own homes. This research takes apart that American Dream by examining the preferences of different income and family life cycle groups for housing and neighborhood characteristics associated with the housing bundle. Based on a sample of Syracuse metropolitan respondents, this research applies the factorial survey method to assess the variations in housing preferences by socio-economic status and family composition. Findings show that all groups of respondents were indifferent to housings' tenure. All respondents desired single family housing but the intensity of these preferences for single family homes over other types of housing varied among subgroups. Strong desires were expressed not to live among blacks nor lower income households, although respondents expressed no desires for either suburban locations or physically homogeneous neighborhoods. These findings suggest that surface desires for homeownership may proxy for desires to control local racial and socio-economic composition.

Immediate Response to Headwater Flooding in Charlotte, North Carolina

This article examines the immediate responses to the headwater flooding of two structurally homogeneous neighborhoods in Charlotte, North Carolina, one predominantly black and the other predominantly white. The results of the research suggest that the distress and disruption caused by noncatastrophic floods are a genuine neighborhood issue, even in neighborhoods with other serious problems like crime, lack of parks and recreation areas, speeding traffic, and unemployment. Faced with frequent flood damage, a significant number of property owners were willing to assume some monetary costs for protecting their homes and safety, but residents of the white neighborhood were not amenable to remedial measures that would necessitate relocation out of their neighborhood. Respondents in both neighborhoods appeared to possess a realistic understanding of the causes of flooding and its financial impact on property values. However, a significant subgroup of blacks viewed flooding as an uncontrollable natural event and were less confident of their ability to deal with the hazard. Residents of both neighborhoods strongly favored increased public sector involvement in implementing adjustments to the flooding hazard.

Some experiments in waveform approximation

Two methods of waveform approximation were compared, one based on maximal homogeneous neighborhoods, the other on recursive subdivision of nonuniform subintervals. The compactness/error tradeoff was found to favor the former method.

Chicago sociology and urban planning policy

This account has provided one illustration of the possibility of an alternative approach to the sociology of knowledge other than the “reductionist” analysis of ideas as mere epiphenomena of material interests. If the sociology of knowledge cannot be pursued in any other fashion, the field's oft-lamented neglect seems entirely justifiable. But sociologists of knowledge can choose to define the purpose of their work, not as the exposure of perceptual distortions conditioned by social position, but as the elucidation of factors which lend certain formulations plausibility within a given socio-cultural context. Ironically, such explication of the relationship of ideology to work has been consonant with the developing Chicago tradition, although not unique to it, for Chicagoans have been concerned to elucidate the means by “which people respond creatively to the limitations of their institutional context.” As we have seen, the pre-World War II manifestation of that tradition has permitted urban bureaucrats to maximize their possibilities for action within the constraints of their formal obligations. Not only has their faith in the accuracy of evolutionist predictions sustained civil servants in the belief that they have maintained value-neutrality, but it has also allowed them to enjoy the pleasures of power and concrete accomplishment. For the city is conceptualized as an ever-expanding frontier, perpetually subjected to cycles of devastation and construction. Hence, while ostensibly acting as instruments of inexorable historical forces, urban bureaucrats are constantly provided with opportunities to raise tangible monuments to their personal authority. And evolutionist sociology has sanctioned a viable occupational strategy for the bureaucrat qua bureaucrat, for it justifies the civil servants' favored relationship with powerful clients, allowing them to negotiate their continued occupational survival. Although Chicago sociology has proved useful to planning professionals, I do not mean to suggest that its creators would have approved of the consequences of bureaucratic activity. In fact, both in method and substance the practices of government agencies have violated the human ecologists' ideal; Chicagoan Louis Wirth deplored planners' operational categories, arguing that they should be replaced with more sophisticated sociological ones. More importantly, federal officials used Chicago sociologists' projections to support policies counter to the Chicagoans' prescriptions for civilized society. Government policy has been effectively anti-urban. Based on the Chicago evolutionists' model, and in the name of sound business practices, central city decline has been assured and suburban expansion facilitated. Chicago sociologists saw conflict arising from large-scale urban migration and rapid industrialization, but they accepted conflict as necessary to progress; the highest development of civilization required diversity and an urban milieu. Within the city various groups created homogeneous communities, but heterogeneity of the population as a whole was essential to urban culture. Federal agencies, while adhering to the sociologists' premises, turned the model on its head; they sought to minimize conflict by eradicating social heterogeneity, and encouraged the growth of homogeneous suburban neighborhoods in which residents were protected from alien persons and lifestyles.

The effects of nonresidential land uses on the prices of adjacent housing: Some estimates of proximity effects

This paper reports the results of 16 market experiments designed to produce measures of the effects of nonresidential land uses on the prices of nearby dwellings. Each experiment consists of a sample of home sales in a homogeneous neighborhood located near a single nonresidential land use, e.g., industry, commercial, high-density dwellings, and highways. The data consist of price, physical characteristics of the dwelling, distance from the nonresidential use, and the date of sale for each transaction. Hedonic price indices are estimated and the significance of the distance effects assessed. No systematic relationship between nonresidential land use per se and housing prices is found.