2,179 research outputs found
Estimation and model selection in generalized additive partial linear models for correlated data with diverging number of covariates
We propose generalized additive partial linear models for complex data which
allow one to capture nonlinear patterns of some covariates, in the presence of
linear components. The proposed method improves estimation efficiency and
increases statistical power for correlated data through incorporating the
correlation information. A unique feature of the proposed method is its
capability of handling model selection in cases where it is difficult to
specify the likelihood function. We derive the quadratic inference
function-based estimators for the linear coefficients and the nonparametric
functions when the dimension of covariates diverges, and establish asymptotic
normality for the linear coefficient estimators and the rates of convergence
for the nonparametric functions estimators for both finite and high-dimensional
cases. The proposed method and theoretical development are quite challenging
since the numbers of linear covariates and nonlinear components both increase
as the sample size increases. We also propose a doubly penalized procedure for
variable selection which can simultaneously identify nonzero linear and
nonparametric components, and which has an asymptotic oracle property.
Extensive Monte Carlo studies have been conducted and show that the proposed
procedure works effectively even with moderate sample sizes. A pharmacokinetics
study on renal cancer data is illustrated using the proposed method.Comment: Published in at http://dx.doi.org/10.1214/13-AOS1194 the Annals of
Statistics (http://www.imstat.org/aos/) by the Institute of Mathematical
Statistics (http://www.imstat.org
Experimental analysis for the effect of dynamic capillarity on stress transformation in porous silicon
The evolution of real-time stress in porous silicon(PS) during drying is investigated using micro-Raman spectroscopy. The results show that the PS sample underwent non-negligible stress when immersed in liquid and suffered a stress impulsion during drying. Such nonlinear transformation and nonhomogeneneous distribution of stress are regarded as the coupling effects of several physical phenomena attributable to the intricate topological structure of PS. The effect of dynamic capillarity can induce microcracks and even collapse in PSstructures during manufacture and storage.This work is funded by the National Natural Science
Foundation of China Contract Nos. 10732080 and
10502014
Pride, prejudice and pragmatism: family language policies in the UK
In this study, we examine how mobility and on-going changes in sociocultural contexts impact family language policy (FLP) in the UK. Using a questionnaire and involving 470 transnational families across the UK, our study provides a descriptive analysis of different family language practices in England and establishes how attitudes influence the different types of FLP in these families. Complementing the descriptive analysis, we use interview data to understand the driving forces behind the different types of language practices and language management activities, and explore how ideological constructs of ‘pride’, ‘prejudice’ and ‘pragmatism’ are directly related to negative or positive attitudes towards the development of children’s heritage language. The findings indicate that migration trajectories, social values, raciolinguistic policing in schools, and linguistic loyalty have shaped family decisions about what languages to keep and what languages to let go. Our paper responds to the linguistic and demographic changes in British society, and makes an important contribution to our knowledge about multilingual development of children in transnational families. Critically, this study shows that FLPs alone cannot save the minority languages; institutionally sanctioned language practices and ideologies have to make a move from limiting the use of these languages in educational contexts to legitimising them as what they are: linguistic resources and languages of pride
Pride, prejudice and pragmatism:family language policies in the UK
In this study, we examine how mobility and on-going changes in sociocultural contexts impact family language policy (FLP) in the UK. Using a questionnaire and involving 470 transnational families across the UK, our study provides a descriptive analysis of different family language practices in England and establishes how attitudes influence the different types of FLP in these families. Complementing the descriptive analysis, we use interview data to understand the driving forces behind the different types of language practices and language management activities, and explore how ideological constructs of ‘pride’, ‘prejudice’ and ‘pragmatism’ are directly related to negative or positive attitudes towards the development of children’s heritage language. The findings indicate that migration trajectories, social values, raciolinguistic policing in schools, and linguistic loyalty have shaped family decisions about what languages to keep and what languages to let go. Our paper responds to the linguistic and demographic changes in British society, and makes an important contribution to our knowledge about multilingual development of children in transnational families. Critically, this study shows that FLPs alone cannot save the minority languages; institutionally sanctioned language practices and ideologies have to make a move from limiting the use of these languages in educational contexts to legitimising them as what they are: linguistic resources and languages of pride.<br/
Introduction:The changing faces of transnational communities in Britain
In this editorial introduction, we outline the key conceptualisations andoverarching questions of this collection of studies on the changing faces of thetransnational communities in Britain. Using the nexus of migration and languageas our critical lens, we examine the internal diversities within the transnationalcommunities in Britain, evident in the emergence of groups differing on migrationtrajectories, social and educational backgrounds, linguistic repertories and statusassigned to community languages. We also explore how language shapes, and isshaped by, these internal diversities and wider socio-cultural-political dynamicsand pay particular attention to the multilingual and translanguaging practices inthese communities. We demonstrate how these communities function as sites forcontestation of language and identity that can be conflictual as well as a source ofothering. The introduction concludes with an outline of the contributions made bythe studies in this special issue, highlighting the key claims put forward by thecontributors
Pride, prejudice and pragmatism:family language policies in the UK
In this study, we examine how mobility and on-going changes in sociocultural contexts impact family language policy (FLP) in the UK. Using a questionnaire and involving 470 transnational families across the UK, our study provides a descriptive analysis of different family language practices in England and establishes how attitudes influence the different types of FLP in these families. Complementing the descriptive analysis, we use interview data to understand the driving forces behind the different types of language practices and language management activities, and explore how ideological constructs of ‘pride’, ‘prejudice’ and ‘pragmatism’ are directly related to negative or positive attitudes towards the development of children’s heritage language. The findings indicate that migration trajectories, social values, raciolinguistic policing in schools, and linguistic loyalty have shaped family decisions about what languages to keep and what languages to let go. Our paper responds to the linguistic and demographic changes in British society, and makes an important contribution to our knowledge about multilingual development of children in transnational families. Critically, this study shows that FLPs alone cannot save the minority languages; institutionally sanctioned language practices and ideologies have to make a move from limiting the use of these languages in educational contexts to legitimising them as what they are: linguistic resources and languages of pride.<br/
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