农村基本公共品的社区供给:山东省30个村庄的调查

一、概念界定与研究方法 1、概念界定 "农村基本公共品"作为本文的主要概念对象,其内涵限定于国际通行的发展中国家"基本社会服务"范畴,即指基础公共生活设施(生活用水、供电、村庄道路)、初级教育、初级医疗、养老服务和社会救助等最基本的生活资源."所有这些服务对于保证基本的生活质量、维持人们的劳动力和健康都是最必需的"①;联合国发展组织通常也根据类似的定义界定基本社会服务或产品的内涵②.这些基本的生活性公共品或服务以社区居民为直接受益者、在某种程度具有萨缪尔森(Samuelson)所定义的消费的非竞争性、受益的非排他性③以及效用的不可分性特征.由此,本文所研究的基本公共品属于基础性社会服务和生活资料,与那些生产性公共品和其他社会性公共品(如治安、精神文明教育等)有所区别.     

Gene‐environment correlations in the cross‐generational transmission of parenting: Grandparenting moderates the effect of child 5‐HTTLPR genotype on mothers' parenting

Evidence suggests that parenting is associated cross‐generationally and that children's genes may elicit specific parenting styles (evocative gene‐environment correlation). This study examined whether the effect of children's genotype, specifically 5‐HTTLPR, on mothers' parenting behaviors was moderated by her own parenting experiences from her mother. Two independent samples of three‐year‐olds (N = 476 and 405) were genotyped for the serotonin transporter gene, and observational measures of parenting were collected. Mothers completed measures of the parenting they received as children. The child having a short allele on 5‐HTTLPR was associated with more maternal hostility (Samples 1 and 2) and with less maternal support (Sample 1), but only if the mother reported lower quality grandmothers' parenting (abuse and indifference in Sample 1 and lower levels of grandmother care in Sample 2). Results support the possibility of a moderated evocative gene‐environment correlation.     

The seasonality of births in Canada: A comparison with the northern United States

This paper presents evidence that there are substantial differences in the seasonal birth patterns of Canada and the northern United States. The seasonal birth pattern in Canada is characterized by a birth peak in April–May, and a trough in December–January. The birth pattern in the northern U.S. is characterized by a trough in April–May, and a peak in August–September. The influence of climate on the birth patterns is explored in an attempt to explain the discrepancies. In both Canada and the United States, there is an inverse relationship between temperature and conceptions during the summer months. The study concludes that variation in temperature alone cannot explain the discrepancy between the birth patterns of southern Canada and the northern United States.     

Intimate partner violence during pregnancy and use of antenatal care among rural women in southern Terai of Nepal

Background

Underutilisation of antenatal care services due to intimate partner violence during pregnancy has been well documented elsewhere, but it is understudied in Nepal. Our study aimed at exploring the impact of intimate partner violence on antenatal care service utilisation in southern Terai of Nepal.

Iso‐chi‐squared testing of 2 × k: ordered tables

The Pearson chi‐squared statistic for testing the equality of two multinomial populations when the categories are nominal is much less appropriate for ordinal categories. Test statistics typically used in this context are based on scorings of the ordinal levels, but the results of these tests are highly dependent on the choice of scores. The authors propose a test which naturally modifies the Pearson chi‐squared statistic to incorporate the ordinal information. The proposed test statistic does not depend on the scores and under the null hypothesis of equality of populations, it is asymptotically equivalent to the likelihood ratio test against the alternative of two‐sided likelihood ratio ordering.     

Analysis of an unreliable MX/G1G2/1/repeated service queue with delayed repair under randomized vacation policy

Abstract

In this article we consider an unreliable M^X/G/1 queue with two types of general heterogeneous service and optional repeated service subject to server’s break down and delayed repair under randomized vacation policy. We assume that customer arrive to the system according to a compound Poisson process. The server provides two types of general heterogeneous service and a customer can choose either type of service before its service start. After the completion of either type of service, the customer has the further option to repeat the same type of service once again. While the server is working with any types of service or repeated service, it may breakdown at any instant. Further the concept of randomized vacation is also introduced. For this model, we first derive the joint distribution of state of the server and queue size by considering both elapsed and remaining time, which is one of the objective of this article. Next, we derive Laplace Stieltjes transform of busy period distribution. Finally, we obtain some important performance measure and reliability indices of this model.     

Dynamic relationships between children’s higher‐order regulation and lower‐order reactivity predict development of attention problems

Dual‐process theories contend that interplay between higher‐order (i.e., regulatory) and lower‐order (i.e., reactive) systems influences the development of attention in early childhood. We therefore investigated interactions between an aspect of children's top‐down self‐regulation (i.e., effortful control; EC) and positive reactivity (indexed by observed positive affectivity; PA) and negative reactivity (indicated by cortisol stress reactivity and observed fear) in predicting children's early attention problems. We found that observed EC at the age of three predicted lower attention problems 2 years later, controlling for attention problems at baseline. Importantly, the predictive effect of EC was more pronounced for children higher in cortisol stress reactivity at the age of three; this pattern was not found for observed PA or fear. Findings align with dual‐process developmental theories that emphasize the dynamics between regulatory and reactive processes in shaping child development. Our study provides the first evidence supporting dual‐process interactions in the domain of attention problems and has implications for identifying early risk markers and informing early prevention programs for children at greater risk for attention problems.     

The Changing Colour of Poverty in Canada*

À partir des données des recensements canadiens de 1991 et de 1996, nous nous penchons sur la question des immigrants pauvres et à faible revenu, un sujet très peu traité dans les travaux de recherche précédents sur l'immigration. Comparativement aux Canadiens de souche, les immigrants sont constamment surreprésentés dans la classe des pauvres. Cette surreprésentation comporte une orientation ethnique et raciale claire: les immigrants appartenant aux minorités visibles vivant les pires conditions. Les modèles de régression logis‐tique révèlent que, dans leur cas, les chances d'être pauvres sont con‐sidérablement plus élevées même en tenant compte de toutes les autres variables pertinentes. Les taux de pauvreté des différentes générations d'immigrants ne suivent pas un modèle logique; ceux qui ont émigréà l'adolescence vivent dans des conditions anormales de pauvreté extrême. La comparaison entre la situation des immigrants en 1991 et en 1996 révèle que l'investissement en matière de capital humain favorise de moins en moins les immigrants. Using the 1991 and 1996 Canadian census data, the present study addresses the issue of poor or low‐income immigrants, a topic largely overlooked in previous immigration research. The authors found that, compared to native‐born Canadians, immigrants were consistently over‐represented among the poor, and that this over‐representation had a clear ethnic and racial colour, with visible minority immigrants experiencing the most severe conditions. For them, the logistic regression models show, the odds of poverty are noticeably higher, even after controlling for all other relevant variables. The poverty rates of different generations of immigrants also show an unexpected pattern, in which those who have migrated during their adolescent years experience unusually severe poverty conditions. A comparison of the situation in 1991 and 1996 shows that human capital endowments are becoming less rewarding for immigrants.     

Combinatorics of TCP reordering

We study a combinatorial problem motivated by a receiver-oriented model of TCP traffic from Istrate et al. (2006), that incorporates information on both arrival times, and the dynamics of packet IDs. An important component of this model is a many-to-one mapping FB from sequences of IDs into a sequence of buffer sizes. We show that: i) Given a buffer sequence B, constructing a sequence A of IDs that belongs to the preimage of B is no harder than finding matchings in bipartite graph. ii) Counting the number of sequences A of packet IDs that belong to the preimage of B can be done in linear time in the special case when there exists a constant upper bound on the maximum entry in B. iii) This problem also has a fully polynomial randomized approximation scheme when we have a constant upper bound on the number of repeats in the packet sequences in the preimage. We also provide experimental evidence that the two previous results suffice to efficiently count the number of preimages for buffer sequences observed in real TCP data.