What Cruising Infants Understand about Support for Locomotion

“Cruising” infants can only walk using external support to augment their balance. We examined cruisers' understanding of support for upright locomotion under four conditions: cruising over a wooden handrail at chest height, a large gap in the handrail, a wobbly unstable handrail, and an ill‐positioned low handrail. Infants distinguished among the support properties of the handrails with differential attempts to cruise and handrail‐specific forms of haptic exploration and gait modifications. They consistently attempted the wood handrail, rarely attempted the gap, and occasionally attempted the low and wobbly handrails. On the wood and gap handrails, attempt rates matched the probability of cruising successfully, but on the low and wobbly handrails, attempt rates under‐ and overestimated the probability of success, respectively. Haptic exploration was most frequent and varied on the wobbly handrail, and gait modifications—including previously undocumented “knee cruising”—were most frequent and effective on the low handrail. Results are discussed in terms of developmental changes in the meaning of support.     

Improved cross-entropy method for estimation

The cross-entropy (CE) method is an adaptive importance sampling procedure that has been successfully applied to a diverse range of complicated simulation problems. However, recent research has shown that in some high-dimensional settings, the likelihood ratio degeneracy problem becomes severe and the importance sampling estimator obtained from the CE algorithm becomes unreliable. We consider a variation of the CE method whose performance does not deteriorate as the dimension of the problem increases. We then illustrate the algorithm via a high-dimensional estimation problem in risk management.     

Social networks and the organisation of big business groups in post New Economic Policy (NEP) era in the 1990s in Malaysia

Personal ties are generally regarded as important to big business growth in Malaysia, particularly after the New Economic Policy (NEP) in the 1990s. Common types are informal ones established between multi-ethnic big business people and Malay key state and political leaders. Other types of ties, company directorship links and informal ties, are seldom studied especially those between the business people and former state bureaucrats and corporate professionals. Thus, by conceptualising the directorship links and informal personal ties as social networks, the author conducted a sociological analysis of some intra- and inter-ethnic directorship links and ties established by four prominent big businessmen after the NEP in the 1990s. This article reports the main finding on the links and ties becoming a common organisational mechanism of business groups owned and controlled by the businessmen, besides providing access to the state. Therefore, another understanding of inter- and intra-ethnic personal ties in big business growth, especially after the NEP is achieved.     

New recursive estimators of the time-average variance constant

Estimation of the time-average variance constant (TAVC) of a stationary process plays a fundamental role in statistical inference for the mean of a stochastic process. Wu (2009) proposed an efficient algorithm to recursively compute the TAVC with \(O(1)\) memory and computational complexity. In this paper, we propose two new recursive TAVC estimators that can compute TAVC estimate with \(O(1)\) computational complexity. One of them is uniformly better than Wu’s estimator in terms of asymptotic mean squared error (MSE) at a cost of slightly higher memory complexity. The other preserves the \(O(1)\) memory complexity and is better then Wu’s estimator in most situations. Moreover, the first estimator is nearly optimal in the sense that its asymptotic MSE is \(2^{10/3}3^{-2} \fallingdotseq 1.12\) times that of the optimal off-line TAVC estimator.     

“镇改市”过程中的制约因素与改革进路

“镇改市”是我国基层行政体制改革的试验,也是在新型城镇化过程中对基层行政区划改革做出的有益尝试。以构建大中小城市和小城镇协调发展的城镇化空间格局为目标指向,通过激活中小城市的发展“命脉”,改变单纯依靠经济推动乡镇发展的路径依赖,实现“农民城”向新型城镇的跨越,是中国经济发展的新探索。然而,随着改革的推进,缺位的行政规划设计、有限的乡镇管理能力、被异化的政绩观念、社会组织发育不成熟以及市民文化普及不到位等,对“镇改市”的推进造成一定程度的制约,成为“镇改市”过程中难以回避的现实问题。问题的化解离不开政策的引导、技术的支持和法治的保障,这三个维度相互联系、缺一不可,共同为“镇改市”改革的顺利实施“保驾护航”。     

On Bartlett correction of empirical likelihood for regularly spaced spatial data

Bartlett correction constitutes one of the attractive features of empirical likelihood because it enables the construction of confidence regions for parameters with improved coverage probabilities. We study the Bartlett correction of spatial frequency domain empirical likelihood (SFDEL) based on general spectral estimating functions for regularly spaced spatial data. This general formulation can be applied to testing and estimation problems in spatial analysis, for example testing covariance isotropy, testing covariance separability as well as estimating the parameters of spatial covariance models. We show that the SFDEL is Bartlett correctable. In particular, the improvement in coverage accuracies of the Bartlett‐corrected confidence regions depends on the underlying spatial structures. The Canadian Journal of Statistics 47: 455–472; 2019 © 2019 Statistical Society of Canada     

Vegetation on and around large-scale buildings positively influences native tropical bird abundance and bird species richness

High population growth in the tropics is driving urbanisation, removing diverse natural ecosystems. This is causing native species to suffer while introduced synanthropes flourish. City planners are developing urban greenspace networks, in part trying to address this issue. Architects contribute to these greenspace networks by designing elevated and ground level green spaces on large-scale buildings. However, little evidence is available on whether building green spaces support native fauna. This is true for birds in tropical Singapore that support important ecosystem services and have existence value. Therefore, in this study, we conducted bird surveys and statistical analyses to determine, if and how vegetation on three building green space types (ground gardens, roof gardens and green walls) have a positive impact on native or introduced bird species. We found that elevated greenery (roof gardens and green walls) on large-scale buildings supported a higher richness of birds and abundance of urban native birds than control roofs and walls without vegetation. Ground gardens supported similar levels of native species as roof gardens but also a larger proportion of generalist synanthropes. However, we found no tropical forest habitat specialists across any space type. Therefore, we recommend roof gardens and ground gardens as a potential space for urban natives outside of a less competitive ground-level urban environment. Our study also found certain building design elements (height of elevated space, presence of specific plants) supported different species groups. Therefore, we suggest that these ecological requirements for different species groups are considered when designing a building’s green space.

     

An increase in song pitch of eastern great tits (Parus minor) in response to urban noise at Seoul,Korea

Urban Ecosystems - Anthropogenic noise may mask effective vocal signal transmission by birds, particularly in notes occurring in lower frequencies. Previous studies have shown a correlation of...     

The risks and incentives of disciplinary neoliberal feminism: the case of microfinance

This article develops an analysis of the concept of disciplinary neo-liberal feminism through a focus on gendered poverty alleviation strategies and illustrates the value of this through a discussion of microfinance. By locating this study within an analysis of the expansion of global capital accumulation, the article argues that the liberal frameworks of female empowerment and entrepreneurialism that are central to these programs and to feminism in this form, mask their underlying political, social and economic objectives. In contrast, a Marxist Feminist approach more adequately explains the interplay of class and gender that underpins poverty alleviation strategies. This article argues that in the context of financial crisis and reduced social provision, women living in poverty in the Global South were identified as targets for the expansion of global finance. Their integration into global financial networks via microfinance and other pro-poor strategies has facilitated the expansion of markets for credit while at the same time disciplining market participation through the twin forces of risk and incentive. Disciplinary neo-liberal feminism has underpinned this incorporation of women into global capital accumulation creating profound effects for households and families, with microfinance programs representing important sites of contestation for the politics of class and gender.     

Father's Migration and Leaving the Parental Home in Rural Mozambique

Migration is an increasingly common global phenomenon and has important implications for the well‐being of family members left behind. Although extensive research has examined the impact of parental labor migration on school‐age children, less is known about its effect on adolescents. In this study, the authors used longitudinal survey data collected in rural Mozambique (N = 515) to assess the association between father's migration and adolescent children's leaving the parental home, an important component of the transition to adulthood. The results showed that father's migration delays home‐leaving for adolescent girls and that these effects are not mediated by school enrollment. The results for boys were inconclusive. The authors also found that remittances and longer durations of paternal migration were negatively associated with the transition out of the home. On the basis of the findings, they argue that father's migration delays girls' marriage.