M-quantile models with application to poverty mapping

Over the last decade there has been growing demand for estimates of population characteristics at small area level. Unfortunately, cost constraints in the design of sample surveys lead to small sample sizes within these areas and as a result direct estimation, using only the survey data, is inappropriate since it yields estimates with unacceptable levels of precision. Small area models are designed to tackle the small sample size problem. The most popular class of models for small area estimation is random effects models that include random area effects to account for between area variations. However, such models also depend on strong distributional assumptions, require a formal specification of the random part of the model and do not easily allow for outlier robust inference. An alternative approach to small area estimation that is based on the use of M-quantile models was recently proposed by Chambers and Tzavidis (Biometrika 93(2):255–268, 2006) and Tzavidis and Chambers (Robust prediction of small area means and distributions. Working paper, 2007). Unlike traditional random effects models, M-quantile models do not depend on strong distributional assumption and automatically provide outlier robust inference. In this paper we illustrate for the first time how M-quantile models can be practically employed for deriving small area estimates of poverty and inequality. The methodology we propose improves the traditional poverty mapping methods in the following ways: (a) it enables the estimation of the distribution function of the study variable within the small area of interest both under an M-quantile and a random effects model, (b) it provides analytical, instead of empirical, estimation of the mean squared error of the M-quantile small area mean estimates and (c) it employs a robust to outliers estimation method. The methodology is applied to data from the 2002 Living Standards Measurement Survey (LSMS) in Albania for estimating (a) district level estimates of the incidence of poverty in Albania, (b) district level inequality measures and (c) the distribution function of household per-capita consumption expenditure in each district. Small area estimates of poverty and inequality show that the poorest Albanian districts are in the mountainous regions (north and north east) with the wealthiest districts, which are also linked with high levels of inequality, in the coastal (south west) and southern part of country. We discuss the practical advantages of our methodology and note the consistency of our results with results from previous studies. We further demonstrate the usefulness of the M-quantile estimation framework through design-based simulations based on two realistic survey data sets containing small area information and show that the M-quantile approach may be preferable when the aim is to estimate the small area distribution function.     

Asymptotic Properties and Variance Estimators of the M-quantile Regression Coefficients Estimators

M-quantile regression is defined as a “quantile-like” generalization of robust regression based on influence functions. This article outlines asymptotic properties for the M-quantile regression coefficients estimators in the case of i.i.d. data with stochastic regressors, paying attention to adjustments due to the first-step scale estimation. A variance estimator of the M-quantile regression coefficients based on the sandwich approach is proposed. Empirical results show that this estimator appears to perform well under different simulated scenarios. The sandwich estimator is applied in the small area estimation context for the estimation of the mean squared error of an estimator for the small area means. The results obtained improve previous findings, especially in the case of heteroskedastic data.     

Approximate Bayesian computation with composite score functions

Both approximate Bayesian computation (ABC) and composite likelihood methods are useful for Bayesian and frequentist inference, respectively, when the likelihood function is intractable. We propose to use composite likelihood score functions as summary statistics in ABC in order to obtain accurate approximations to the posterior distribution. This is motivated by the use of the score function of the full likelihood, and extended to general unbiased estimating functions in complex models. Moreover, we show that if the composite score is suitably standardised, the resulting ABC procedure is invariant to reparameterisations and automatically adjusts the curvature of the composite likelihood, and of the corresponding posterior distribution. The method is illustrated through examples with simulated data, and an application to modelling of spatial extreme rainfall data is discussed.     

Understanding foraging flexibility in urban vervet monkeys,Chlorocebus pygerythrus,for the benefit of human-wildlife coexistence

Urban Ecosystems - Generalist wildlife species often thrive in urban environments because of increased anthropogenic resources. However, human-wildlife interactions, especially if negative, raise...     

'You cannot get enough of them!’ The rise (and fall) of complementary therapies in British nursing practice in the 1980s and 1990s

This paper examines the emerging use of complementary therapies in British nursing practice at the end of the twentieth century. Many nurses turned to complementary therapies as a means to provide a closer therapeutic relationship with their patients and this paper will establish how nurses were informed and empowered. The paper places complementary practices in the context of nursing developments in the closing decades of the twentieth century and concludes that the extent of the supporting networks that encouraged nurses to incorporate these therapies into their work was more significant than has been previously recognised and exemplifies a distinct period in the history of modern nursing.     

Urban ecosystem Services in Latin America: mismatch between global concepts and regional realities?

Urban Ecosystems - Latin America and the Caribbean (LAC) is one of the most urbanized and biologically diverse regions in the world but is often characterized by weak environmental governance and...     

Challenges of operationalizing trauma‐informed practice in child protection services in New Zealand

New Zealand is undergoing major change in service delivery to children and families. A new Ministry for Children Oranga Tamariki has been established to oversee 5 work streams, one of which provides intensive intervention with families requiring a statutory response to child protection concerns. The government minister responsible promised that the service would be child‐centred and trauma‐informed. To date, these terms remain undefined, and there is no shared understanding of their meaning. Practice frameworks to support the work of the new ministry are still being developed, creating something of a vacuum in the meantime. The focus of this paper is the challenge of implementing trauma‐informed practice in the child protection service provided by the Intensive Intervention work stream. Limited research or commentary on trauma‐informed practice in this context currently exists. Drawing on the relevant available literature, the concept and its application in child protection social work is explored. An ecological framework is used to discuss the changes needed to achieve this. Particular attention is paid to the impact of historical trauma for indigenous people due to New Zealand's colonial history and their over‐representation in care and protection services.     

Male dominance and sexism on YouTube: results of three content analyses

This study conceptually and empirically extends a study by Wotanis and McMillan in which the authors claimed that female video producers are underrepresented on YouTube and receive much more negative (including hostile and sexist) feedback than male YouTubers. Using quantitative content analysis, this study supported the claim of female underrepresentation. Among the top 100 most subscribed YouTube channels in nine different countries (N = 900 channels), with a statistically significant proportion of only 25%, female video producers were strongly underrepresented. Additionally, a second content analysis of N = 2,400 video comments directly replicated the original study’s main quantitative results. This analysis confirmed that the popular female US comedy YouTuber Jenna Mourey (“JennaMarbles”) received much more negative (including hostile and sexist) feedback than her male counterpart Ryan Higa (“nigahiga”). However, a third content analysis of N = 6,000 video comments from five other pairs of comparable comedy YouTubers did not reveal that women’s videos generally attract a larger number of negative video comments. Possibly, women attract more negative comments only if they display their sexuality (like Jenna Mourey) or address feminist topics, but not if they conform to gender role expectations. Future research directions and practical implications are discussed.     

Assessing Prejudice Toward Two-Father Parenting and Two-Mother Parenting: The Beliefs on Same-Sex Parenting Scale

This article describes two interrelated studies that investigated beliefs and stereotypes on two-father parenting and two-mother parenting through the development and validation of the Beliefs on Same-Sex Parenting (BOSSP) scale. The BOSSP captures two beliefs: (1) prejudices toward same-sex couples’ inherent inability to parent and (2) concerns about same-sex parenting that are not necessarily related to homonegativity. In Study 1 (301 heterosexual participants), exploratory factor analysis (EFA) suggested an 11-item scale for attitudes toward both two-father families and two-mother families, with two factors: parenting skills, which evaluates beliefs on same-sex couples’ ability to take care of their children; and parental adjustment, which assesses beliefs on the impact of challenges related to same-sex parenting on children’s well-being. Support for convergent validity between BOSSP factor scores and those of theoretically related measures were provided. In Study 2 (346 heterosexual participants surveyed in two time points), CFA indicated that the two-factor model provided the best fit. Test-retest reliability and longitudinal invariance were documented. Finally, results revealed that more negative attitudes toward same-sex parenting were held by men than by women and were associated with negative opinions on reproductive techniques. The innovative characteristics of the BOSSP and implications for future practice are discussed.