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Which GRS statistic is appropriate for cross-sectional tests of linear multi-factor pricing models?
No full textFama and French (2015, 2017) introduce the five-factor asset pricing model in the former paper and test their model on data from international financial markets in the latter paper. Each paper tests whether the five-factor model represents returns by way of the Gibbons, Ross and Shanken (1989) (hereafter GRS) statistic. That statistic’s null hypothesis jointly sets all cross-section intercepts (alpha) to zero. The GRS statistic developed and presented in equation (4) on page 1124 of GRS (1989) is a cross-section test of the one-factor capital asset pricing model. Using the same data as Fama and French (2015, 2017), we show that the latter authors did not use the GRS (1989) statistic given in equation (4) on page 1124. In fact, they used a version of that statistic appropriate for the five-factor model. To provide clarity on this issue, this paper provides a detailed mathematical derivation of the cross-sectional variance of the OLS estimators of the intercepts when N versions of the K-factor model are estimated. This variance is then used to construct the enhanced version of the GRS statistic. Its finite sample distribution is then rigorously established. To obtain that distribution, restrictions are made on cross-sectional variances and covariances of the errors of pricing models that are inconsistent with times series data. We derive the variance-covariance of the estimated intercepts of the K-factor model without making these restrictions. An almost sure approximation to that estimator is constructed here which is then used to obtain the asymptotic distribution of the GRS statistic. We call it the robust GRS statistic. Using data of Fama and French (2015, 2017), we use the robust GRS statistic to reconstruct their Tables 5 and 4, respectively. As the distribution of the robust GRS does not change with the number of factors, in contrast to the finite sample version of this statistic, it allows for a more nuanced comparison of three-, four- and five-factor models. The power functions of the GRS (1989) statistic is compared with the enhanced version of the GRS appropriate for K factors
Beyond ‘dust and mud’ : citizenship, governance, and the politics of peri-urban road infrastructure in Kumasi
No full textThis article explores the governance of peri-urban road infrastructure and its implications for citizenship and agency of urban residents in Kumasi, Ghana. It focuses on understanding the reasons behind the prolonged neglect of peri-urban roads, the resulting precarious living and working conditions, the agency of residents in responding to these challenges and the transformative impact of newly constructed roads. It draws on 33 qualitative interviews and the theoretical frameworks of the right to the city, infrastructural citizenship and insurgent citizenship. The article reveals that road improvement decisions are shaped not only by physical conditions (dusty or muddy nature) but also traffic volume, political interests, resource constraints and multi-level governance. Infrastructure neglect exacerbates socio-economic vulnerabilities, disrupting business activities, constraining mobility and generating public health risks, reflecting decaying citizenship. In response, communities mobilize through self-help initiatives and protest to assert their infrastructural rights. While road improvements can catalyze socio-economic transformation, they may also introduce new risks such as increased road crashes caused by speeding vehicles. The article contributes to understanding road governance, community resilience and urban transformation in rapidly urbanising African cities
Who cares? Opportunities and challenges posed by agile working practices for carers employed in a higher education faculty in the South-East of England
No full textCaring responsibilities increasingly impact workforces. Expanding agile working practices presents a potential solution to address competing demands between familial and employment responsibilities. This study aimed to explore the perceptions of academic staff with caring responsibilities and their managers regarding the benefits and challenges of agile working. Nineteen participants (n = 10 staff, n = 9 managers) took part in focus groups conducted in a faculty at a Higher Education Institution (HEI) in South-east England between March and July 2022. Data was reflexively thematically analyzed. Staff and manager groups had similar experiences of agile working and perceived multi-generational caring challenges. The benefits of agile working were flexibility, improved professional outputs, and better physical and mental well-being. Challenges included professional relationships and unmet technology and infrastructure needs. A desire to continue and optimize agile working was expressed. There was recognition that further guidance was needed to define expectations for carers. Faculty-wide recommendations generated from this study offer a first step in developing infrastructure to support academic staff with caring responsibilities at one HEI. These may, with development, inform HEI policy development and frameworks, and have wide-reaching implications
Mechanical and in situ thermal-related behavior during directed energy deposition additive manufacturing of a high-performance Al alloy
Full text linkDirected energy deposition (DED) additive manufacturing (AM) can fabricate, repair, and join near-net-shaped components for high-performance engineering applications, including biomedical, energy, and transport sectors. The broader adoption of DED remains constrained by the limited number of alloys available that can be reliably manufactured without imperfections, hence limiting mechanical properties. Here, we designed an Al–Ni–Ce–Mn–Fe AM alloy that can achieve an ultra-fine microstructure (<5 μm), uniform distribution of intermetallics, low residual stress (<32 MPa), and superior mechanical properties in as-built DED components. Compared to DED AlSi10Mg in the as-built state using the same conditions, the yield increased by 70%, and the ultimate tensile strength by 50%. DED-AM involves rapid cooling and complex thermal conditions, which largely influence the property of the final components. Post-characterization cannot capture the time resolved thermal behavior, hence offer limited mechanism-based guide for alloy design. In this study, we develop a novel multimodal characterization methodology for correlative in situ X-ray imaging, X-ray diffraction, and infrared imaging, enabling quantification of the in situ thermal-related behavior, including phase evolution, temperature distribution, and stress accumulation during DED. We elucidated key mechanisms driving the structure refinement and stress development in this alloy. The insights gained into the interplay between alloy composition, thermal-related behavior, and performance under specific AM conditions inform next-generation material design tailored for AM technologies
Stakeholders' interpretations and responses to research as a feature of advanced practice : a scoping review
Full text linkBackground.
Although clinical practice has been prioritised and operationalised globally, research activities remain underdeveloped and inconsistently supported in advanced practice roles. A focus on clinical tasks limits the growth of advanced practitioners as research leaders, negatively impacting job satisfaction, retention, and progression into consultant-level practice. Stakeholder attitudes and actions are central to shaping advanced practitioners’ engagement with research and their professional development. However, the interpretation and response to research as a core component remain poorly understood. This knowledge gap risks ineffective efforts to strengthen the research pillar of advanced practice, highlighting the need to better understand stakeholder perspectives to integrate research more effectively into advanced practice.
Objective.
This scoping review aims to map how stakeholders interpret and respond to research within advanced practice and identify gaps in the conceptual, methodological, and theoretical aspects of the literature.
Information Sources.
A systematic search was conducted in CINAHL, MEDLINE, and the British Nursing Database, focusing on English-language literature published between 2013 and 2025.
Methods.
Following the Joanna Briggs Institute method for scoping reviews and informed by the Patterns, Advances, Gaps, Evidence for Practice, and Research Recommendations framework, data were extracted, analysed, and synthesised. Data were presented in tabular form and supplemented with a narrative synthesis.
Results.
The findings were mapped into four categories: 1) Research as a Role Expectation, 2) Contextual Factors Shaping Research, 3) Educational Preparation for Research, and 4) Interventions Supporting Research. While research is an expected feature of advanced practice, its engagement is often hindered by time constraints, heavy clinical workloads, lack of leadership, insufficient education, and limited clinical-academic collaboration. Research activities are commonly assessed using traditional metrics, such as publications, while neglecting ‘soft’ outcomes, including increased confidence, skill development, and influence on team culture. Furthermore, many studies lacked theoretical frameworks, limiting their explanatory power.
Conclusions.
Research appears underdeveloped but is narrowly defined in advanced practice, often measured by traditional outputs rather than processes and impacts on learning and development. This review highlights the need for a comprehensive, theory-informed approach to understanding research in advanced practice. Such insights are crucial for shaping educational curricula, professional development, and organisational strategies to better support advanced practitioners as leaders and contributors to healthcare innovation
Revisiting cost of poor quality in the digital era : evidence from global survey organisations
No full textPurpose: This study investigates contemporary practices in measuring and managing the Cost of Poor Quality (COPQ), the distribution of costs across the four classic Cost of Quality (COQ) categories, the influence of COPQ information on managerial decisions, and the continuing relevance of Mikel Harry's COPQ benchmarks in a digitalised context. Methodology: Data were collected via an online global survey (175 respondents) and analysed using descriptive statistics, chi-square tests, and Random Forest classification. Findings: The findings show that COPQ is often measured only in selected functions; many organisations struggled to analyse COPQ as a percentage of sales revenue; and internal and external failure costs frequently remain in double-digit ranges, while prevention costs spending is relatively low. COPQ information is most strongly used at the operational level and less in strategic and tactical decisions. Moreover, Mikel Harry's benchmark figures (COPQ is equal to 1% at Six Sigma quality level, 25% at Three Sigma quality level of the sales revenue) are viewed more as heuristics than as universal truths. Originality: The study offers new evidence on COPQ measurement, links COPQ to Operational Excellence (OpEx) and Quality 4.0 (Q4.0) initiatives and demonstrates the value of predictive analytics for understanding departmental drivers of quality costs.
Rewired gene interactions during evolution of the analia and genitalia in Drosophila
No full textDrosophila ventral appendages are considered to be serially homologous derived from a ventral appendage ‘ground state’ and shaped by different Hox inputs. The male and female terminalia (analia and genitalia) are highly derived ventral structures defined by Abdominal-B and the sex-determination pathway. In the legs and antennae a combination of the transcription factors (TF) C15, LIM1 homeobox 1 (Lim1) and Al (Aristaless) is required for tarsal claw and arista development, respectively. However, the roles of these TFs in terminalia development remained unexplored. We investigated the expression and function of C15, Lim1 and Al during male and female terminalia development. We found that C15 plays distinct roles in males and females, repressing male clasper bristles while promoting bristles on the female epiproct. Contrasting with antennae and legs, C15, Lim1 and Al are not all simultaneously co-expressed in any terminal structure in either sex, indicating interactions among these factors have diverged across these appendages. Nevertheless, we inferred interactions between C15 and other factors reflecting similarities between leg and male clasper development. Finally, we identified a male-specific C15 enhancer active in male claspers but not in the female epiproct, legs or antennae. This C15 enhancer modularity may underpin tissue- and sex-specific regulatory logic
Quality improvement and the UNSDGs : mapping industry contributions at the goal, target and indicator levels
No full textThe study examines the extent to which industry-led quality improvement projects contribute to the United Nations Sustainable Development Goals (UNSDGs). The objective is to map these contributions to the UNSDGs, targets, and indicators to provide a detailed understanding of sustainability alignment through quality management (QM) projects. A qualitativequantitative content analysis was conducted on 41 award-nominated Indian case studies submitted to the International Academy for Quality (IAQ) Quality Sustainability Award. Each project was mapped to primary and secondary SDG goals and aligned with relevant SDG targets and indicators. The study found that SDG 12 and SDG 9 were the most frequently addressed goals. Even though most projects primarily targeted environmental and economic SDGs, direct attention to social goals was comparatively limited and was more often reflected as secondary contributions than as the primary focus. Approximately one-third of projects submitted to the IAQ award demonstrated cross-SDG contributions, suggesting the multidimensional benefits of integrated quality and sustainability initiatives. The study provides new empirical insights into the contribution of QM to UNSDGs