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Recent years have witnessed the world-wide emergence of mega-metropolises with incredibly huge populations. Understanding residents mobility patterns, or urban dynamics, thus becomes crucial for building modern smart cities. In this paper, we propose a Neighbor-Regularized and context-aware Non-negative Tensor Factorization model (NR-cNTF) to discover interpretable urban dynamics from urban heterogeneous data. Different from many existing studies concerned with prediction tasks via tensor completion, NR-cNTF focuses on gaining urban managerial insights from spatial, temporal, and spatio-temporal patterns. This is enabled by high-quality Tucker factorizations regularized by both POI-based urban contexts and geographically neighboring relations. NR-cNTF is also capable of unveiling long-term evolutions of urban dynamics via a pipeline initialization approach. We apply NR-cNTF to a real-life data set containing rich taxi GPS trajectories and POI records of Beijing. The results indicate: 1) NR-cNTF accurately captures four kinds of city rhythms and seventeen spatial communities; 2) the rapid development of Beijing, epitomized by the CBD area, indeed intensifies the job-housing imbalance; 3) the southern areas with recent government investments have shown more healthy development tendency. Finally, NR-cNTF is compared with some baselines on traffic prediction, which further justifies the importance of urban contexts awareness and neighboring regulations. [ABSTRACT FROM AUTHOR]

There is often considerable anxiety and conflicting advice concerning the benefits of presenting/being evaluated first. We thus investigate how expert evaluators vary in their evaluations of entrepreneurial proposals based upon the order in which they are evaluated. Our research setting is a premiere innovation fund competition in Beijing, China, where the prize money at stake is economically meaningful, and evaluators are quasi-randomly assigned to evaluate written grant proposals without the possibility of peer influence. This enables us to credibly recover a causal position effect. We also theorize and test how heterogeneity in evaluators' prior (context-specific) judging experience moderates position effects. Overall, we find that a proposal evaluated first requires total assets in the top 10th percentile to merely equal the evaluation of a proposal in the bottom 10th percentile that is not evaluated first. Firm and evaluator fixed-effects models yield consistent findings. We consider evaluation design elements that may mollify these position effects in the discussion section. This paper was accepted by Sridhar Tayur, entrepreneurship and innovation. [ABSTRACT FROM AUTHOR]

This study aims to estimate the migration effect of the overall samples and different flowing scales for the floating population from the perspective of personal wages. Although we used both the OLS and PSM methods to estimate the migration effect, we found that the PSM method was preferred in the study of migration as a result of the selection bias. The empirical results show that there is a significant difference in wage before and after migration. In fact, migration increased wages by 15.18% to 23.63% overall. Additionally, wages were increased by 44.96% to 59.20%, 23.06% to 26.18%, and 10.89% to 15.08% respectively for these three migration patterns: flowing into the three largest megacities, inter-provincial migration, and inter-city migration within a province, but for this pattern of inter-district migration within a city, the migration effect is not significant. We concluded that the floating population removing policies of the largest megacities maybe are effective because of the administrative power of their government. On the other hand, for these policies of non-largest megacities to attract labor and local employment and local urbanization near the floating population’s place of origin, they were not effective enough as a result of the lack of significant migration effect in these cities. [ABSTRACT FROM AUTHOR]

Migrants usually exhibit similar or better health outcomes than native-born populations despite facing socioeconomic disadvantages and barriers to healthcare use; this is known as the “migrant paradox.” The migrant paradox among children is highly complex. This study explores whether the migrant paradox exists in the health of internal migrant children in China and the role of schools in reducing children’s health disparities, using a multi-stage stratified cluster sampling method. Participants were 1,641 student and parent pairs from Grades 4, 5, and 6 of eight primary schools in Beijing. The following school types were included: state schools with migrant children comprising over 70% of total children (SMS), private schools with migrant children comprising over 70% (PMS), and state schools with permanent resident children comprising over 70% (SRS). Children were divided into Groups A, B, C or D by the type of school they attended (A and B were drawn from SRSs, C was from SMSs, and D was from PMSs) and whether they were in the migrant population (B, C, and D were, but A was not). Related information was collected through medical examination and questionnaires completed by parents and children. Prevalence of caries, overweight and obesity, poor vision, and self-reported incidence of colds and diarrhea in the previous month were explored as health outcomes. The results partially demonstrated the existence of the migrant paradox and verified the role of schools in lowering health disparities among children; there are theoretical and practical implications for improving the health of migrant children. [ABSTRACT FROM AUTHOR]

Purpose: The cerebrospinal fluid pressure (CSFP) is a major determinant of central retinal vein pressure and thus of retinal capillary pressure. We tested the hypothesis whether prevalence and severity of diabetic retinopathy are associated with CSFP. Methods: The population-based Beijing Eye Study 2011 included 3468 individuals with a mean age of 64.6±9.8 years. A detailed ophthalmic examination was performed including fundus photography for the assessment of diabetic retinopathy according. Based on a previous study with lumbar cerebrospinal fluid pressure (CSFP) measurements, CSFP was calculated as CSFP[mmHg] = 0.44xBody Mass Index[kg/m2]+0.16 Diastolic Blood Pressure[mmHg]–0.18xAge[Years]−1.91. Results: In binary regression analysis, presence of diabetic retinopathy was significantly associated with higher levels of HbA1c (P<0.001; regression coefficient B:0.25; odds ratio (OR):1.28; 95% confidence interval (CI):1.15,1.43), higher blood concentration of glucose (P<0.001; B:0.40;OR:1.49;95%CI:1.36,1.63), longer known duration of diabetes mellitus (P<0.001; B:0.14;OR:1.15; 95%CI:1.11,1.19), higher systolic blood pressure (P<0.001; B:0.03;OR:1.03;95%CI:1.02,1.04), lower diastolic blood pressure (P<0.001; B:−0.06;OR:0.94;95%CI:0.91,0.97), and higher CSFP (P = 0.002; B:0.13;OR:1.14;95%CI:1.05,1.24). Severity of diabetic retinopathy was significantly associated with higher HbA1c value (P<0.001; standardized coefficient beta: 0.19; correlation coefficient B: 0.07;95%CI:0.05,0.08), higher blood concentration of glucose (P<0.001; beta:0.18;B:0.04;95%CI:0.04,0.05), longer known duration of diabetes mellitus (P<0.001; beta:0.20;B:0.03;95%CI:0.02,0.03), lower level of education (P = 0.001; beta:−0.05;B:−0.02;95%CI:−0.03,−0.01), lower diastolic blood pressure (P = 0.002; beta:−0.08;B:−0.001;95%CI:−0.004,−0.001), higher systolic blood pressure (P = 0.006; beta:0.06;B:0.001;95%CI:0.000,0.001), and higher CSFP (P = 0.006; beta:0.06;B:0.006;95%CI:0.002,0.010). Conclusions: Higher prevalence and severity of diabetic retinopathy were associated with higher estimated CSFP after adjusting for systemic parameters. Higher CSFP through a higher retinal vein pressure may lead to more marked retinal venous congestion and vascular leakage in diabetic retinae. [ABSTRACT FROM AUTHOR]