Effects Of Spatial Density Research Articles

Urban agglomeration, city size, and spatial density effects on wage flexibility: New evidence on the wage curve in Brazil

AbstractThis study aims to shed new empirical light on the importance of the wage curve in a developing economy. The main contribution to the empirical literature is related to the analysis being conducted at different regional levels of a developing economy. This indicates that municipal‐level data seems to be more adequate for wage curve evaluation, and that spatial dependency should be considered to adequately control for local labor market characteristics. Results for Brazil show that wage flexibility is higher in less dense local labor markets and in the informal sector. Controlling for unobserved local characteristics is necessary to obtain the ‘true’ elasticity of wages with respect to local unemployment rates, while spatial autocorrelation effects should be accounted for when the spatial unit of analysis is rather small to consider the interactions that happen inside a specific labor market area. Finally, a significant part of the difference in outcomes between formal and informal sectors appears to originate from spatial–economic dependence effects, indicating that labor market areas are more suitable for such analysis.

Effects of spatial density on veterinarian income: where are all of the veterinarians?

ABSTRACTWith increased numbers of veterinarians in the market, it is critical to understand how this increased competition affects income potential at multiple levels. This study presents an empirical approach that incorporates local and nonlocalised spatial competition of firms into one model. By analysing the market for veterinarians using a spatial weight matrix approach, we are able to quantify localized and nonlocalised competition which assists in defining relevant market areas for veterinarians. Specifically, increased density within their county and surrounding counties decreases veterinarian income. Thus, the potential market area for veterinarians is larger than the local/county market in which they practice. This is important for veterinarians when choosing a location to practice, as they must consider the competition and demand in local and non-local areas.

Evidence‐based evaluation of the cumulative effects of ecosystem restoration

AbstractThis study adapts and applies the evidence‐based approach for causal inference, a medical standard, to the restoration and sustainable management of large‐scale aquatic ecosystems. Despite long‐term investments in restoring aquatic ecosystems, it has proven difficult to adequately synthesize and evaluate program outcomes, and no standard method has been adopted. Complex linkages between restorative actions and ecosystem responses at a landscape scale make evaluations problematic and most programs focus on monitoring and analysis. Herein, we demonstrate a new transdisciplinary approach integrating techniques from evidence‐based medicine, critical thinking, and cumulative effects assessment. Tiered hypotheses about the effects of landscape‐scale restorative actions are identified using an ecosystem conceptual model. The systematic literature review, a health sciences standard since the 1960s, becomes just one of seven lines of evidence assessed collectively, using critical thinking strategies, causal criteria, and cumulative effects categories. As a demonstration, we analyzed data from 166 locations on the Columbia River and estuary representing 12 indicators of habitat and fish response to floodplain restoration actions intended to benefit culturally and economically important, threatened and endangered salmon. Synthesis of the lines of evidence demonstrated that hydrologic reconnection promoted macrodetritis export, prey availability, and juvenile fish access and feeding. Upon evaluation, the evidence was sufficient to infer cross‐boundary, indirect, compounding, and delayed cumulative effects, and suggestive of nonlinear, landscape‐scale, and spatial density effects. Therefore, on the basis of causal inferences regarding food‐web functions, we concluded that the restoration program is having a cumulative beneficial effect on juvenile salmon. The lines of evidence developed are transferable to other ecosystems: modeling of cumulative net ecosystem improvement, physical modeling of ecosystem controlling factors, meta‐analysis of restoration action effectiveness, analysis of data on target species, research on critical ecological uncertainties, evidence‐based review of the literature, and change analysis on the landscape setting. As with medicine, the science of ecological restoration needs scientific approaches to management decisions, particularly because the consequences affect species extinctions and the availability of ecosystem services. This evidence‐based approach will enable restoration in complex coastal, riverine, and tidal‐fluvial ecosystems like the lower Columbia River to be evaluated when data have accumulated without sufficient synthesis.

A SPATIAL ECOLOGY OF STRUCTURAL HOLES: SCIENTISTS AND COMMUNICATION AT A BIOTECHNOLOGY FIRM.

The article contends that the effects of spatial density on network formation should be considered in tandem with the social attributes of spatially agglomerated actors. It focuses on the competiti...

The Effects of Spatial Density on the Social Interaction of Preschool Children with Disabilities

There has been limited research on the effects of spatial density on the social interaction of preschool children, particularly those with disabilities. Further, findings of existing studies need to be viewed cautiously due to a number of methodological difficulties including contrived small groupings of children and atypical intervention settings. The effect of varying the spatial density during the regular indoor free play session in a community preschool was investigated in the current study. A single subject alternating treatment design was used to compare the effectiveness of three spatial conditions (small, medium and large) on the social interaction of three children with disabilities or significant language delay. Examination of the findings revealed no consistent pattern of difference in the frequency of peer social interaction in the spatial conditions for two of the target children. There was, however, a modest treatment effect favouring the small condition for a third participant with a language delay. Questions are raised about the efficacy of the intervention for children with significant disabilities in inclusive preschool settings.

Human and spatial dimensions of retail density: Revisiting the role of perceived control

AbstractPrevious research in environmental psychology and consumer behavior has demonstrated mostly negative effects of human density on consumer experience in retail settings. The effects of spatial density, however, have received scant attention. Results from previous studies show that retail density affects shoppers' emotional and behavioral responses through perceived control.Work in social psychology, however, indicates that there are differences in the extent to which people strive for control, suggesting that having control in retail settings may be more important to some consumers than to others. In the experimental study reported in this paper, the effects of both forms of retail density were studied as a function of consumers' desire for control. Results indicate that the effects of human and spatial density vary with consumers' desire for control. Theoretical and managerial implications are discussed. © 2008 Wiley Periodicals, Inc.

Spatial density as a setting event for the social interaction of preschool children

The effects of spatial density as a setting event on the social interaction of preschool children were examined in this review. A specific interest was the potential application of this setting event to children with special needs in inclusive settings. Twelve studies were examined revealing a range of methodological and technical difficulties in the extant research. Several studies reported significant effects, but results were inconsistent and very limited research examining students with special needs is available. Several suggestions for future research are offered including conduct of studies in typical preschool settings with representative group sizes, study of children with special needs, and use of research designs that allow idiosyncratic responses to interventions to be considered. Despite considerable recent interest and research on setting events, the body of research on spatial density is dated and methodologically problematic. It is suggested that renewed interest in this class of setting events might be appropriate.

A reversal in the direction of detection asymmetry: effects of spatial density, spatial regularity, and retinal eccentricity.

We analyzed detection asymmetry, using openand closed squares as target and contextelements. It was found that varying density, regularity, and target eccentricity not only can modulate the amount of asymmetry, but also can produce a reversal in the direction of the asymmetry. The results suggest that the different stimuli are processed with different grains of analysis,consisting of in some cases, single elements and their properties and, in other cases, larger units of the stimulus array and more globalproperties. A detection task that can utilize the properties that are available with a given grain of analysis would show an advantage over a task for which the given grain of analysis is not as favorable, resulting indetection asymmetry in one direction or another.

Depth in anticorrelated stereograms: Effects of spatial density and interocular delay

Disparity-based depth is not perceived in densely textured, anticorrelated random-dot stereograms (RDSs) whose elements carry opposite signs of brightness coatrast on corresponding loci, as extant data show. We observed global depth in anticorrelated RDSs flashed repetitively with an interocular delay. During the delay time, a dot array in one eye was paired with a gray frame hi the other eye and thus could interact with the negative afterimage of the contralateral dot array. A correlated RDS (e.g. 8 min arc dots, 50% density, 15-msec flash duration) lost depth with delays > 45 msec. An anticorrelated RDS, that was otherwise identical, showed robust depth when flashed with an interocular delay of some 60 msec. A delay was not always necessary to produce depth. At low dot density (1–2%), anticorrelated RDSs showed disparity-dependent local depth even when displayed continuously, or flashed simultaneously; as dot density alone was increased, depth was progressively lost. To make global depth visible in a dense RDS flashed with an interocular delay, the internal response had to be strongly biphasic. Our results support the generally held notion that cyclopean depth signals emerge exclusively from same-sign binocular cortical filters. However, the exclusionary rule may be invalid with respect to the processing of coarse local depth with figural stimuli. Relative depth between a pair of small dots was easily perceived when one of the dots was in opposite contrast, but the depth threshold was then about 0.5 log unit higher than with the same-contrast pair of dots indicating that the internal effects of contrast have not all lost their sign prior to binocular disparity processing. It remains to be determined whether depth can be perceived from edges of opposite contrast.

A factor analytic approach to the study of spatial density effects on preschoolers

A factor analytic approach to the study of spatial density effects on preschoolers

Behavior Problem Indices

The differential effects of spatial density on five year-old children who were divided into "low" and "high" on dimensions of hyperactivity-distractibility, anxiety, hostility-aggressiveness, behavior disturbance, and motor inhibition were examined. Sex differences in interaction with the above behavioral dimensions were also investigated. In general, normal children motorically adjusted to a high-density condition to a greater degree than children with behavior problems. Anxious and impulsive children were especially distressed by a high-density condition, compared to normals.

The Effects of Spatial Density on the Social Behavior of Children1

The behavioral effects of high and low spatial density on normal children of ages 4 and 5 were examined. Sixty Ss were observed in groups of six in a free‐play situation under both density conditions. Results showed that there was significantly less aggression and less social interaction in the high‐density condition than in the low‐dcnsity condition. Thcrc was a significant Density X Sex effect o n aggression and signficant main effects of sex on aggression, nurturance, number of interruptions, and number of children interacted with. Several complexities in researching and explaining the effects of density on behaviors are discussed.