Assimilation vs. multiculturalism: Views from a community in France

A recent American survey of attitudes toward societal multiculturalism vs. assimilation has found surprisingly widespread support for maintaining heritage cultures not only among immigrant minority groups but also among most subsamples of majority host groups, black and white. Working-class whites are the one exception. This pilot study explores the same attitude domain in a contrasting European setting. Randomly selected samples of middle- and working-class families (a mother, father, and teenage son or daughter) from a small city in France were interviewed. As a group, they were neutral to slightly favorable to immigrants maintaining heritage cultures and languages rather than losing them through assimilation. On measures of attitudes toward specific immigrant groups, there were marked intergroup dyfferunces with Maghrebian Arabs rated leist favorably and Southeast Asians, the model immigrants, most favorably. Comparisons of subgroups of respondents who varied in terms of (a) political left-right orientation, (b) social class standing, (c) degree of religiosity, and (d) generational level provide the base for a more general discussion of cultural assimilation and multiculturalism.     

Split Hamiltonian Monte Carlo

We show how the Hamiltonian Monte Carlo algorithm can sometimes be speeded up by “splitting” the Hamiltonian in a way that allows much of the movement around the state space to be done at low computational cost. One context where this is possible is when the log density of the distribution of interest (the potential energy function) can be written as the log of a Gaussian density, which is a quadratic function, plus a slowly-varying function. Hamiltonian dynamics for quadratic energy functions can be analytically solved. With the splitting technique, only the slowly-varying part of the energy needs to be handled numerically, and this can be done with a larger stepsize (and hence fewer steps) than would be necessary with a direct simulation of the dynamics. Another context where splitting helps is when the most important terms of the potential energy function and its gradient can be evaluated quickly, with only a slowly-varying part requiring costly computations. With splitting, the quick portion can be handled with a small stepsize, while the costly portion uses a larger stepsize. We show that both of these splitting approaches can reduce the computational cost of sampling from the posterior distribution for a logistic regression model, using either a Gaussian approximation centered on the posterior mode, or a Hamiltonian split into a term that depends on only a small number of critical cases, and another term that involves the larger number of cases whose influence on the posterior distribution is small.     

A new metamodel-based method for solving semi-expensive simulation optimization problems

In this article, a new algorithm for rather expensive simulation problems is presented, which consists of two phases. In the first phase, as a model-based algorithm, the simulation output is used directly in the optimization stage. In the second phase, the simulation model is replaced by a valid metamodel. In addition, a new optimization algorithm is presented. To evaluate the performance of the proposed algorithm, it is applied to the (s,S) inventory problem as well as to five test functions. Numerical results show that the proposed algorithm leads to better solutions with less computational time than the corresponding metamodel-based algorithm.     

Bi-objective multi-resource scheduling problem for emergency relief operations

Abstract

Resource scheduling for emergency relief operations is complex as it has many constraints. However, an effective allocation and sequencing of resources are crucial for the minimization of the completion times in emergency relief operations. Despite the importance of such decisions, only a few mathematical models of emergency relief operations have been studied. This article presents a bi-objective mixed integer programming (MIP) that helps to minimize both the total weighted time of completion of the demand points and the makespan of the total emergency relief operation. A two-phase method is developed to solve the bi-objective MIP problem. Additionally, a case study of hospital network in the Melbourne metropolitan area is used to evaluate the model. The results indicate that the model can successfully support the decisions required in the optimal resource scheduling of emergency relief operations.     

Association between serum levels of testosterone and biomarkers of subclinical atherosclerosis

Objective: To investigate the association between serum levels of testosterone and biomarkers of subclinical atherosclerosis based on data from 119 middle-aged men of the general population.

Methods: Testosterone, Apolipoprotein A-1 (ApoA-1), Apolipoprotein B (ApoB), Apolipoprotein B-to-Apolipoprotein A-1 ratio (ApoB-to-ApoA-1), high-sensitive C-reactive protein (hsCRP), and fibrinogen levels were measured. Data were also gathered based on age, BMI, waist circumference, smoking, alcohol consumption, and family history of cardiovascular diseases. Men were classified into two groups based on testosterone levels: hypogonadal (testosterone ≤12?nmol/L) and eugonadal men (testosterone >12?nmol/L).

Results: When compared to eugonadal, the hypogonadal men were significantly older (56?years vs. 55?years, p?=?.03), had greater BMI (28?kg/cm² vs. 26?kg/cm², p?=?.01), and higher waist circumference (104?cm vs. 100?cm, p?=?.01). Moreover, ApoB, ApoB-to-ApoA-1 ratio, and hsCRP were significantly higher in hypogonadal men compared to eugonadal men (1.1?g/L vs. 1.0?g/L, p?=?.03), (0.8 vs. 0.7, p?=?.03), (3.3?mg/L vs. 2.0?mg/L, p?=?.01), respectively. On the other hand, ApoA-1 and fibrinogen levels did not differ significantly between groups (p?>?.05). In an adjusted multivariate regression analysis model, only ApoB showed a significant negative association with testosterone levels (β?=??0.01; 95% CI?=??0.02, ?1.50; p?=?.04).

Conclusion: Testosterone levels showed an inverse relation to ApoB, a biomarker implicated in subclinical atherosclerosis. These findings support the hypothesis that low testosterone levels play a role in atherosclerosis.     

Hamiltonian Monte Carlo acceleration using surrogate functions with random bases

For big data analysis, high computational cost for Bayesian methods often limits their applications in practice. In recent years, there have been many attempts to improve computational efficiency of Bayesian inference. Here we propose an efficient and scalable computational technique for a state-of-the-art Markov chain Monte Carlo methods, namely, Hamiltonian Monte Carlo. The key idea is to explore and exploit the structure and regularity in parameter space for the underlying probabilistic model to construct an effective approximation of its geometric properties. To this end, we build a surrogate function to approximate the target distribution using properly chosen random bases and an efficient optimization process. The resulting method provides a flexible, scalable, and efficient sampling algorithm, which converges to the correct target distribution. We show that by choosing the basis functions and optimization process differently, our method can be related to other approaches for the construction of surrogate functions such as generalized additive models or Gaussian process models. Experiments based on simulated and real data show that our approach leads to substantially more efficient sampling algorithms compared to existing state-of-the-art methods.     

A Desire to Return to the Country of Birth as a Function of Language Preference: An Empirical Study with Iranian Immigrants in the United States

It was hypothesized that bilingual Iranian immigrants in the United States who prefer to use the Persian language, compared to Iranians who prefer to use English, would be more likely to express a desire to return to Iran to live. Participants were 292 bilingual Iranian immigrants in the United States (128 men, 164 women) who completed a questionnaire with a similar content, prepared in Persian on one side and in English on the other side. Participants were given the option to either complete the Persian or English version of the questionnaire. Results confirmed the research hypothesis suggesting that the immigrants’ preference in using their native language serves as a “pull” factor that increases the probability of a desire to return to the country of birth. It was also found that women and younger respondents were less likely to express a desire to return to Iran. Level of education, marital status, years of living in the United States, and attitudes toward marriage and the family did not predict such a desire. Implications for acculturation research and for counseling culturally diverse clients are discussed. Policy implications to attract immigrants back to their country of birth were also discussed.     

CROSSING TEHRAN AVENUE

The online city magazine TehranAvenue.com (TA) occupies the transnational crossroad of digital and urban space. It thus provides an important case study of how urban studies, postcolonial theory and critical cyber studies can be combined fruitfully to explain the potentialities and limits of digital and social networks in transnational Middle Eastern contexts. The article explores metaphors of the Internet as city, theories of transnational urban space and recent studies of the Internet and its politico-cultural uses in Iran to establish a theoretical method that can explain the simultaneity of local and transnational in digital and urban spaces. Qualitative data (email and telephone interviews with TA's founder, editor and contributors), combined with content analysis of the site, supports the claim that the city as metaphor and metonym can account for the intersection between contemporary North African and Middle Eastern digital spaces and national and diasporic urban spaces. The digital city – or blogabad – expands physical urban space into transnational networks. But there are important limits to the transnational reach of mediated social networking practices. In fact, the located identifications of web users are often much more important than the global reach of the technologies they use.     

A solution to an open problem on lower against number in graphs

In Wang (Appl Anal Discret Math 4:207–218, 2010) the problem of finding a sharp lower bound on lower against number of a general graph is mentioned as an open question. We solve the problem by establishing a tight lower bound on lower against number of a general graph in terms of order and maximum degree.