How do immigrants spend their time? The process of assimilation

Sharp differences in time use by nativity emerge when activities are distinguished by incidence and intensity in recent US data. A model with daily fixed costs for assimilating activities predicts that immigrants are less likely than natives to undertake such activities on a given day; but those who do will spend relatively more time on them. Activities such as purchasing, education, and market work conform to the model. Other results suggest that fixed costs for assimilating activities are higher for immigrants with poor English proficiency or who originate in less developed countries. An analysis of comparable Australian data yields similar results.     

‘At last the family is together’: reproductive futurism in March of the Penguins

This paper offers a resistant reading of the nature documentary March of the Penguins, interrogating its humanist and anthropocentric assumptions. It focuses on the film's reiteration of a politics of reproductive futurism, the belief that children are the future. The figurative association March of the Penguins creates between penguin chick and human child demonstrates the politics of reproductive futurism in manifold ways, but also creates some remarkable ambiguities that can suggest the limitations of such a politics.     

The Accuracy of Age-specific Population Estimates for Small Areas in Britain

Population estimates play an important role in the allocation of resources at many levels of government and commerce but little is known about the accuracy of age-specific population estimates. Such knowledge is crucial, as resource allocation is often targeted at populations of particular age, and decisions need to be based on the reliability of the estimates. This paper presents a multi-level statistical analysis of the accuracy of age-specific population estimates made for British local authorities in 1991. The aim of this work is to identify the factors that influence accuracy, and to investigate how these influences interact. Our analyses show that the following area characteristics are key factors: true population size; intercensal population change; and percentages of unemployed residents, armed forces residents, and students. In addition, we find that the overall type of method used to calculate estimates is important, and that its effect varies both with area characteristics and with age-group. Local census methods are found to be generally superior, but a low-cost apportionment method, if implemented well, may be as effective.     

Distance constrained vehicle routing problem to minimize the total cost: algorithms and complexity

Journal of Combinatorial Optimization - Given $$\lambda >0$$ , an undirected complete graph $$G=(V,E)$$ with nonnegative edge-weight function obeying the triangle inequality and a depot...     

Foreign aid,public investment,and the informal economy

This paper examines the absorption of foreign aid in the presence of formal and informal production. Calibrating a two-sector open economy model to 67 aid-recipient countries for 1990–2019, we show that an increase in foreign aid drives resources into the informal sector, and away from the formal sector. With untied aid, the expansion of the informal sector can lead to an economic contraction through the Dutch Disease effect. An economic expansion with an increase in the share of formal production can be attained by re-allocating existing aid to public investment rather than an increase in the aggregate level of aid.     

Effects of Social Context on Deliberate Facial Expressions: Evidence from a Stroop-like Task

Journal of Nonverbal Behavior - Facial expressions contribute to nonverbal communication, social coordination, and interaction. Facial expressions may reflect the emotional state of the expressor,...     

Associations between acoustic features of maternal speech and infants’ emotion regulation following a social stressor

Caregiver voices may provide cues to mobilize or calm infants. This study examined whether maternal prosody predicted changes in infants’ biobehavioral state after the still face, a stressor in which the mother withdraws and reinstates social engagement. Ninety-four dyads participated in the study (infant age 4–8 months). Infants’ heart rate and respiratory sinus arrhythmia (measuring cardiac vagal tone) were derived from an electrocardiogram (ECG). Infants’ behavioral distress was measured by negative vocalizations, facial expressions, and gaze aversion. Mothers’ vocalizations were measured via a composite of spectral analysis and spectro-temporal modulation using a two-dimensional fast Fourier transformation of the audio spectrogram. High values on the maternal prosody composite were associated with decreases in infants’ heart rate (β = ?.26, 95% CI: [?0.46, ?0.05]) and behavioral distress (β = ?.23, 95% CI: [?0.42, ?0.03]), and increases in cardiac vagal tone in infants whose vagal tone was low during the stressor (1 SD below mean β = .39, 95% CI: [0.06, 0.73]). High infant heart rate predicted increases in the maternal prosody composite (β = .18, 95% CI: [0.03, 0.33]). These results suggest specific vocal acoustic features of speech that are relevant for regulating infants’ biobehavioral state and demonstrate mother–infant bi-directional dynamics.     

Exemplar or matching: modeling DCJ problems with unequal content genome data

The edit distance under the DCJ model can be computed in linear time for genomes with equal content or with Indels. But it becomes NP-Hard in the presence of duplications, a problem largely unsolved especially when Indels (i.e., insertions and deletions) are considered. In this paper, we compare two mainstream methods to deal with duplications and associate them with Indels: one by deletion, namely DCJ-Indel-Exemplar distance; versus the other by gene matching, namely DCJ-Indel-Matching distance. We design branch-and-bound algorithms with set of optimization methods to compute exact distances for both. Furthermore, median problems are discussed in alignment with both of these distance methods, which are to find a median genome that minimizes distances between itself and three given genomes. Lin–Kernighan heuristic is leveraged and powered up by sub-graph decomposition and search space reduction technologies to handle median computation. A wide range of experiments are conducted on synthetic data sets and real data sets to exhibit pros and cons of these two distance metrics per se, as well as putting them in the median computation scenario.     

Tabu search for the real-world carpooling problem

Carpooling is a flexible shared transportation system which can effectively reduce the vehicle numbers and fuel consumption. Although many carpooling systems have been proposed, most of them lack practicality, veracity, and efficiency. In this paper, we propose a new useful variant model of the long-term carpooling problem which involves multiple origins and one destination. Such problems commonly occur in a wide number of carpooling situations in real-world scenarios. Our work is motivated by the practical needs to solve environmental pollution, parking problems, traffic jams and low utilization of resources. A Tabu search algorithm is proposed in this paper to solve the carpooling problem. The proposed algorithm aims at a wide range of passenger distribution and routing problems. The computational results based on real world user data show the effectiveness of the proposed algorithm. Moreover, we developed a mobile application based on our carpooling model.