Investigating Light Curve Modulation via Kernel Smoothing. I. Application to 53 fundamental mode and first-overtone Cepheids in the LMC

Recent studies have revealed a hitherto unknown complexity of Cepheid pulsation. We implement local kernel regression to search for both period and amplitude modulations simultaneously in continuous time and to investigate their detectability, and test this new method on 53 classical Cepheids from the OGLE-III catalog. We determine confidence intervals using parametric and non-parametric bootstrap sampling to estimate significance and investigate multi-periodicity using a modified pre-whitening approach that relies on time-dependent light curve parameters. We find a wide variety of period and amplitude modulations and confirm that first overtone pulsators are less stable than fundamental mode Cepheids. Significant temporal variations in period are more frequently detected than those in amplitude. We find a range of modulation intensities, suggesting that both amplitude and period modulations are ubiquitous among Cepheids. Over the 12-year baseline offered by OGLE-III, we find that period changes are often non-linear, sometimes cyclic, suggesting physical origins beyond secular evolution. Our method more efficiently detects modulations (period and amplitude) than conventional methods reliant on pre-whitening with constant light curve parameters and more accurately pre-whitens time series, removing spurious secondary peaks effectively.Comment: Re-submitted including revisions to Astronomy and Astrophysic

Income Inequality, Cohesiveness and Commonality in the Euro Area: A Semi-Parametric Boundary-Free Analysis

The cohesiveness of constituent nations in a confederation such as the Eurozone depends on their equally shared experiences. In terms of household incomes, commonality of distribution across those constituent nations with that of the Eurozone as an entity in itself is of the essence. Generally, income classification has proceeded by employing “hard”, somewhat arbitrary and contentious boundaries. Here, in an analysis of Eurozone household income distributions over the period 2006–2015, mixture distribution techniques are used to determine the number and size of groups or classes endogenously without resort to such hard boundaries. In so doing, some new indices of polarization, segmentation and commonality of distribution are developed in the context of a decomposition of the Gini coefficient and the roles of, and relationships between, these groups in societal income inequality, poverty, polarization and societal segmentation are examined. What emerges for the Eurozone as an entity is a four-class, increasingly unequal polarizing structure with income growth in all four classes. With regard to individual constituent nation class membership, some advanced, some fell back, with most exhibiting significant polarizing behaviour. However, in the face of increasing overall Eurozone inequality, constituent nations were becoming increasingly similar in distribution, which can be construed as characteristic of a more cohesive society

Partially Identified Poverty Status: A New Approach to Measuring Poverty and the Progress of the Poor.

Poverty measurement and the analysis of the progress (or otherwise) of the poor is beset with difficulties and controversies surrounding the definition of a poverty line or frontier. Here, using ideas from the partial identification literature and mixture models, a new approach to poverty measurement is proposed which avoids specifying a frontier, the price is that an agent's poverty status is only partially identified. Invoking variants of Gibrat's law to give structure to the distribution of outcomes for homogeneous subgroups of a population within the context of a finite mixture model of societal outcomes facilitates calculation of the probability of an agent's poverty status. From this it is straightforward to calculate all the usual poverty measures as well as other characteristics of the poor and non poor subgroups in a society. These ideas are exemplified in a study of 47 countries in Africa over the recent quarter century which reveals among other things a growing poverty rate and a growing disparity between poor and non poor groups not identified by conventional methods.Poverty Frontiers, Mixture Models, Gibrat\'s law, Partial Identification

Abatement and Allocation in the Pilot Phase of the EU ETS

We use historical industrial emissions data to assess the level of abatement and overallocation that took place across European countries during the pilot phase (2005-2007)of the European Union Emission Trading Scheme. Using a dynamic panel data model, we estimate the counterfactual (business-as-usual) emissions scenario for EU member states. Comparing this baseline to allocated and verified emissions, we conclude that both overallocation and abatement occurred, along with under-allocation and emissions inflation. Over the three trading years of the pilot phase we find over-allocation of approximately 376 million EUAs (6%) and total abatement at the member state level of 107 Mt CO2 (1.8%). However, due to over-allocation and possible uncertainty about future allocation methodologies, we calculate that emissions inflation of approximately 119 Mt CO2 (2%) occurred, resulting in emissions over the pilot phase being approximately 12 Mt CO2 (0.2%) higher than they would have been in the absence of the EU ETS.Emissions Trading Scheme, Climate Policy, Dynamic Panel Data Analysis

Response of Glass and Liquid Phases in the Vortex lattice to an external AC magnetic field at different frequencies

We individuated a method to distinguish a glass phase from a highly viscous liquid phase in a lattice of vortices, established in type-two superconductors. Our analysis is based on the study of the temperature dependence of numerically obtained 1st and 3rd harmonics curves of the AC magnetic susceptibility, by changing the frequency of the applied AC magnetic field. The harmonics are obtained by integrating the non-linear diffusion equation for the magnetic field, with different voltage-current characteristics, corresponding to the two different phases. This method could be applied to the analysis of experimental curves in order to determine if the detected magnetic response of superconducting samples may be interpreted in terms of vortex glass or Kim-Anderson model.Comment: 6 pages, 5 figures, to be published on Physica

Impact assessment of food policy research a stocktaking workshop: synthesis report

"This stocktaking workshop provided an opportunity for several groups with active interest in impact assessment relating to agricultural policy research to share experiences and views about what constitutes good practice in this field. The sponsoring organizations have had a long-standing concern for the relevance and effectiveness of agricultural and food policy research in general and at IFPRI in particular. That concern has been addressed in past meetings and the time seemed right for a further stocktaking. The focus of this 2004 meeting was on impact assessment experience at IFPRI. IFPRI has, since the mid-1990s, carried out a variety of activities aimed at assessing the impact of its policy research, capacity strengthening, and policy communications programs. The workshop brought together practitioners of such impact assessment work, users of such information, as well as researchers whose activities have been the subject of impact assessment. The cogency and necessity of such impact accounting work was reaffirmed in general terms. There was constructively critical commentary on the merits of particular approaches and instruments, such as narrative recordings and more quantitative methods of attempting to measure effects of research investments. The perennial issue of challenging counterfactuals was necessarily addressed, and the practicality of experimental and quasi-experimental methods considered. The need for consistency of assessment approaches between ex post studies (which have been the bulk of IFPRI's experience to date) and ex ante assessment efforts that represent an increasing share of the assessment portfolio was also discussed. There has long been a commitment to work towards a strong impact-orientation “culture” within IFPRI; the workshop concluded that, while there has been progress in working toward mainstreaming such a culture, there is still far to go, and efforts must continue in this direction." from Author's AbstractImpact assessment, Agricultural policy, Food policy Research, Capacity strengthening, Research methods,

Examining the Psychosocial Impacts of Transgenerational Trauma: A Phenomenological Study of Parenting Styles Among African American Women

This qualitative phenomenological study aimed to examine the psychosocial impacts of unresolved grief and trauma within the dynamics of parenting styles of African American women. The theories used to guide this study include family systems theory, first introduced by Murray Bowen in the 1950s, and attachment theory, developed by John Bowlby in 1969, as they intersect and provide a foundation for understanding emotional bonds, social relationships, and parent-child attachment wounds at the core. This phenomenological qualitative study answered the following central research question: “How has trauma exposure affected African American women’s awareness of their traumas within their lived experience and parenting practices?” Data were collected from 15 African American women. Criteria for this study were participants who were born in the United States, at least 25 years of age, a parent, stepparent, or adoptive parent to one or more children, and have adverse childhood experiences. Audio recordings, participant observations, and a reflective journal were used to collect, organize, and analyze the data. The research findings identified eight themes and 12 subthemes to address awareness of trauma and barriers to counseling. Each theme answered the research questions of this phenomenological study. Results from the study suggested that African American women experience contextually multiple psychosocial and intergenerational factors that influence self-perception, interpersonal relationships, help-seeking attitudes, and parenting practices. The research from this study contributed to the gap in the literature on parenting styles, parent-child attachment across generations, and stress-related disorders in the family dynamics of African American mothers. This study provided recommendations for future research on transgenerational trauma and the psychosocial factors related to the lived experiences of African American women in the parenting role. This study could benefit the field of family counseling to help expand access to culturally appropriate counseling interventions for African American women, their families, the church, and governmental agencies to create culturally responsive mentorship programs. Also, this study could prove particularly beneficial for trauma-informed mental health therapists who work with individuals in this population to improve help-seeking behaviors. Overall, the research findings lead to a more insightful understanding of the impact of unresolved trauma in the family systems of African American women to halt transgenerational trauma