Robustness Properties Research Articles

Fire performance and characterization of geopolymer foams using fly ash and coal gangue

The paper introduces foamed geopolymers as effective thermal insulation materials for buildings, with the ability to withstand high temperatures. The production methods for achieving a porous microstructure in geopolymers are discussed, emphasizing the use of foaming agents like aluminium powder. The presented research focuses on developing geopolymer foams from industrial waste materials [fly ash and coal gangue] with enhanced thermal and fire resistance while maintaining robust mechanical properties. The novelty lies in evaluating these foams at a medium-sized panel scale [750 mm x 750 mm x thickness] and assessing their fire resistance through comprehensive tests, differentiating it from existing literature that primarily explores smaller-scale materials. Class F fly ash from Skawina power plant, Poland and waste rock from coal mining KWK Wieczorek, Katowice, Poland were used for preparation of geopolymer foam. The research aims to contribute insights into the fire performance of geopolymer foams under ISO 834-1 fire scenario, paving the way for potential applications as thermal insulation panels in building facilities. Results from fire exposure tests, post-fire mechanical property assessments, SEM observations, EDS analyses, XRD analyses, as well as ageing effects are presented and discussed. While foamed geopolymers demonstrate resilience and fire resistance, variations in their mechanical properties and microstructure due to fire exposure are highlighted. The research underlines the potential of employing geopolymer foams as a sustainable solution for thermal insulation in construction, opening up further exploration and application in the construction industry.

Peripheral Neuropathy Instruments for Individuals with Cancer: A COSMIN-Based Systematic Review of Measurement Properties

Although the literature on patient-reported outcomes (PROMs) continues to expand, challenges persist in selecting reliable and valid instruments for assessing peripheral neuropathy (PN) in patients with cancer. This systematic review aimed to identify all validated self-report PN scales and critically appraise their measurement properties. This review was conducted using the COSMIN methodology for PROMs and the PRISMA statement. Five databases were searched from inception to August 2024, identifying 46 eligible studies and 16 PROMs. Evidence quality ranged from “very low” to “moderate”, with notable inconsistencies in the content and structural validity phases of most instruments. Instruments such as the Chemotherapy-induced peripheral neuropathy assessment tool and the Functional Assessment of Cancer Therapy/Gynecologic Oncology Group–Neurotoxicity demonstrated moderate quality and potential utility in clinical practice, while others, including the Location-based assessment of sensory symptoms in cancer and the Measure of Ovarian Symptoms and Treatment, had insufficient evidence to support their use. Importantly, all PROMs focused on chemotherapy-induced peripheral neuropathy, highlighting a significant gap in instruments addressing other PN causes, such as radiotherapy or tumor-related nerve damage. Further research should prioritize developing and validating instruments for distinct cancer populations, ensuring robust psychometric properties and clinical applicability.

Measures of social connectedness in adult populations: a systematic review

BackgroundPoor social connectedness has been identified as a risk factor for poor mental health but there is a lack of standardisation in how it is measured. This systematic review aimed to identify suitable measures of social connectedness for use in UK adult general populations.MethodsSearches were undertaken in two stages to identify: (1) measures of social connectedness from review articles and grey literature and (2) studies reporting on the psychometric properties of the identified measures. Grey literature and five databases were searched: MEDLINE, Embase and PsycINFO; CINAHL and Web of Science. Studies based on UK adult general populations (16–65 years) or other English language speaking countries with similar cultures (US, Canada, Ireland, Australia and New Zealand) were included. Psychometric evidence was extracted relating to six general domains: conceptual model, content validity, reliability, construct validity, scoring and interpretability, and respondent burden and presentation. A narrative synthesis summarised these psychometric properties.ResultsStage (1) 2,396 studies were retrieved and, 24 possible measures of social connectedness were identified; stage (2) 6,218 studies were identified reporting on psychometrics of identified measures and 22 studies were included. These studies provided psychometric evidence for 10 measures, and we did not find psychometric studies for the other identified measures. Six measures (6/10, 60%) reported assessing loneliness and four (4/10, 40%) reported assessing social support but there was a degree of overlap between the assessments of each concept. There was good evidence of reliability across measures, 90% (9/10) had adequate internal consistency, but evidence of content validity was only available for one scale. Five measures (5/10, 50%) reported on at least half of the psychometric criteria, and these were: UCLA-3 (for loneliness), and MSPSS, F-SozU K-6, SPS-10 and SPS-5 (for social support).ConclusionsThis review identified ten social connectedness measures, and identified UCLA-3, MSPSS, F-SozUK-6, SPS-10, and SPS-5 as having the most robust psychometric properties for the UK adult population. Further testing is required to establish content validity, and to clarify the definition and conceptualisation of social connectedness, to enable standardisation in the approach to measuring social connectedness.

Antiplasmodial Potentials, Phytocompounds and the Possible Toxic Effects of Administration of Ethylacetate Extract of Spondias mombin Linn.

Malaria, caused by Plasmodium parasites, is a global health concern. Natural products, such as plant extracts, are investigated for new antimalarial agents. Spondias mombin, traditionally used for medicinal purposes, was examined for its effects on parasitemia, haematological parameters, antioxidant activities, liver function biomarkers, and serum electrolytes in Plasmodium berghei-infected mice. Mice received varying doses of the ethylacetate extract. Various dosages of the extract and the prescribed medication dramatically slowed the parasite's growth. The extract significantly improved red blood cell (RBC) and platelet counts, particularly at higher doses. Hemoglobin levels were decreased dose-dependently. Antioxidant analysis showed increased superoxide dismutase (SOD), glutathione peroxidase (GPx), and reduced catalase (CAT) activities and malondialdehyde (MDA) levels, indicating robust antioxidant properties. Liver function tests showed mixed effects, with elevated AST, ALP, and TB levels at some doses, yet decreased ALT at the highest dose, suggesting possible hepatoprotective effects. Serum electrolyte levels remained stable. Seventy-eight (78) bioactive components were identified in the extract by GC-MS analysis. The extract demonstrated substantial antimalarial and antioxidant capacities, with minimal liver stress and stable electrolyte levels, suggesting safety as an adjunct therapy for malaria. Further research is needed to ascertain the specific antimalarial bioactive constituents and their mechanisms of action.

Synthesis of silver-decorated titanium dioxide nanostructured films for enhanced visible light photocatalysis

Titanium dioxide (TiO2) has been extensively investigated for applications in photocatalysis due to its stability, nontoxicity, and robust photocatalytic properties. Although thin films of TiO2 are effective in wastewater treatment, their dense structure limits surface accessibility. The oblique angle deposition (OAD) technique can be used to create high surface area nanostructured thin films essential for photocatalytic applications. In this study, OAD was used to grow TiO2 thin films. To extend the activity to the visible light region, plasma-reduced silver (Ag) particles were coupled to the TiO2 surface. The Ag-decorated TiO2 (Ag-TiO2) nanostructured films were fabricated using a custom-built magnetron sputter deposition system with OAD technique capability. Different substrate angles of 0°, 35°, and 70° with respect to the target normal were used. The films were characterized for their structural, compositional, and optical properties. The photodegradation performance was evaluated using methylene blue (MB) as the test analyte under visible light irradiation. The results showed a significant improvement in degradation efficiency using plasma-reduced Ag-TiO2. Substrates tilted at 70° achieved the highest MB degradation efficiency of 89.84% after 5 h exposure. This tilt angle also revealed high surface roughness and high surface area. By tilting the substrate with respect to the target, high surface area thin films can be fabricated. This technique is ideal for applications that depend on the area of contact, such as photocatalysis.

Reliability, validity and developmental sensitivity of the Language Use Inventory (LUI) in the Spanish context

IntroductionThe Language Use Inventory (LUI) is a standardized parent-report questionnaire to assess pragmatic language development in children 18 to 47 months of age. The aim of this study is to describe the translation of the Language Use Inventory (LUI) from English to Spanish and to report findings on the Spanish version's reliability, validity and developmental sensitivity. MethodsThe original English version of the LUI was translated into Spanish. Parents of 236 typically developing children completed the inventory. A sub-sample of 107 participants completed the LUI-Spanish, again within 2 weeks, to assess test-retest reliability. ResultsResults showed that the LUI-Spanish demonstrates robust psychometric properties, exhibiting strong internal consistency and test-retest reliability, as well as good developmental sensitivity. Children's scores showed a decrease with age in the subscales that assess communication with gestures. In contrast, subscales that assess communication with sentences obtained significant higher scores with participants' age. No significant differences were found in terms of gender. ConclusionsFindings indicate that the LUI-Spanish is a suitable tool for assessing the pragmatic skills of toddlers and preschool-aged children.

Cellulose-based underwater superoleophobic coatings with robust anti-viscous oil-fouling property for complex oily wastewater remediation.

Underwater superoleophobic coatings, known for their anti-oil-fouling properties, have garnered significant interest in the context of oily wastewater remediation. However, these coatings encounter challenges in preventing viscous oil contamination and structural damage, and easily become ineffective when treating crude oil/water pollutants. Additionally, the non-renewable and non-biodegradable components pose a huge risk to environmental safety and sustainable development. Herein, a cellulose-based coating that combines robust underwater superoleophobicity with anti-viscous oil-fouling characteristic is designed via the extraction of micro/nanoscale heteromorphic cellulose crystals (EHCC) and subsequent crosslinking with carboxymethyl chitosan (CCS). Leveraging the hierarchical micro/nanostructures constructed by EHCC and intensified hydration capability facilitated by multiple hydrogen bonding interactions, the EHCC-CCS coating demonstrates excellent superhydrophilicity/underwater superoleophobicity and ultralow-viscous oil-adhesion property. Moreover, the EHCC-CCS coating exhibits robust chemical resistance and mechanical tolerance. Importantly, it adapts effectively to various flat and porous substrates, offering outstanding anti-oil-fouling and self-cleaning performances. Notably, the EHCC-CCS-coated textile is applied in separating immiscible oil/water mixtures with varying oil viscosities, and the EHCC-CCS-coated PVDF membrane achieves to purify surfactant-stabilized crude oil/water emulsion. The findings provide a straightforward and cost-effective approach for large-scale production of fully biobased coatings with durable underwater superoleophobicity and excellent anti-viscous oil-fouling capability for complex oily wastewater remediation.

Optimal Sliding Gaussian Control of Quadrotor with a Flexible Structure

Optimal sliding Gaussian control of a quadrotor aerial vehicle with a flexible structure has been demonstrated in six-degree-of-freedom flight simulation to be more robust to structural excitation than a standard proportional-derivative control scheme. A general derivation of the optimal sliding Gaussian controller, including an optimal gain selection algorithm and observer design, is presented. Additionally, a brief development of the equations of motion for a quadrotor with a flexible structure is provided as background for the nonlinear six-degree-of-freedom flight simulation results. Robustness properties of the optimal sliding Gaussian controller are evaluated using singular value analysis of linearized models of the closed-loop quadrotor with a flexible structure. Flight simulation and singular value analysis results illustrate the robustness improvements of optimal sliding Gaussian control over the standard proportional-derivative controller design.

BlockGuard: Advancing digital copyright integrity with blockchain technique

In the swiftly advancing media sector, piracy remains a significant challenge, eroding consumer willingness to pay, undermining rightful economic gains for copyright holders, and diluting creative incentives for content creators. Existing copyright protection mechanisms are inadequate for robust intellectual property safeguarding within complex digital environments, especially lacking in lifecycle tracking, authenticity verification, and dispute resolution. This paper introduces BlockGuard, a pioneering blockchain-based credible digital copyright management system designed to mitigate these issues through strategic use of blockchain and digital watermarking techniques. Furthermore, it enhances issue resolution via the application of Non-Fungible Token (NFT) contracts. BlockGuard aims to achieve three primary objectives. Firstly, it enables comprehensive lifecycle tracking of digital assets, ensuring visibility from content creation to its diverse applications. Secondly, by employing digital watermarking, it provides stringent authenticity verification to drastically reduce copyright infringements. Lastly, leveraging blockchain’s immutability and transparency, it streamlines dispute resolution processes. BlockGuard presents an efficient, secure, and transparent approach for managing digital copyrights in today’s media landscape. It showcases a detailed protection center and public appraisal workflow, and verifies the effectiveness of three originality detection processes. In terms of performance, BlockGuard requires 88% of the storage space on secondary storage compared to conventional solutions (that store only the original image) and incurs minimal storage overhead at the kilobyte level on blockchain storage. Furthermore, its most resource-intensive operation consumes no more than 200,000 gas, with other operations requiring no more than 100,000 gas, equivalent to a standard Ethereum transaction.

Evaluating citrus juice: A comparative study of physicochemical, nutraceutical, antioxidant, and antimicrobial properties of citrus juices from Nepal

Citrus fruit juice is highly beneficial to human health, providing essential nutrients like carbohydrates, vitamins, phytochemicals, and antioxidants. Juices from citrus fruit varieties grown in various regions of Nepal were analyzed for their physicochemical properties, nutraceutical content, antioxidant and antimicrobial properties. The pH of the juices ranged between 2.09 and 3.62, while total soluble solids (TSS) varied from 7° Brix to 12.3 °Brix. Among varieties, C. aurantifolia exhibited the highest titratable acidity at 7.39 g/100 mL. C. limon showed the highest moisture content (94.74 %), C. reticulata had the highest carbohydrate content (14.6 ± 0.4 g/100 mL, n = 3), and C. aurantifolia presented the highest protein content (34.1 ± 0.7 mg/100 mL). C. sinensis recorded the highest flavonoid content (91.4 ± 0.3 mg/100 mL), C. reticulata had the highest phenolic content (65.8 ± 0.6 mg/100 mL), and C. limon exhibited the highest ascorbic acid content (45.1 ± 0.4 mg/100 mL). The methanolic extracts of all citrus fruit juices demonstrated robust antioxidant properties, as determined by DPPH assay. Notably, C. limon and C. aurantifolia juice extracts demonstrated significant antimicrobial activity against a wide range of microbes. This study highlights the variation in nutrient and phytochemicals compositions among different citrus fruit juices, underscoring the nutritional and medicinal benefits of citrus species.

Restraining Planar Gliding in Single-Crystalline LiNi0.9Co0.05Mn0.05O2 Cathodes by Combining Bulk and Surface Modification Strategies.

The delamination cracking from planar gliding along the (003) facets and anisotropic lattice strain perpendicular to the (003) facets inevitable lead to degradation of Ni-rich single-crystal cathode materials, adversely affecting their cyclability. Herein, we rationally design a single-crystal LiNi0.9Co0.05Mn0.05O2 (SC90) cathode with robust chemo-mechanical properties, in which coherently grown MgO6 octahedra and BO4 tetrahedra are incorporated into the lattice, and a stabilizing Mg3(BO3)2 layer is concurrently formed on the particle surface. Multiscale in/ex situ characterizations and theoretical calculations indicate that introducing the MgO6 and BO4 units leads to a "pinning effect" within the layered structure. This in turn strongly mitigates mechanical degradation by reducing planar gliding and delamination cracking over extended cycling. Moreover, the Mg3(BO3)2 coating maintains fast lithium diffusion by suppressing parasitic reactions at the cathode|electrolyte interface. The tailored SC90 cathode exhibits a capacity retention of ~88% after 300 cycles at 5C rate, significantly outperforming the pristine counterpart (~60%). Additionally, a pouch-type full cell with a graphite anode sustains a specific discharge capacity of 177 mAh g-1 after 500 cycles, with 90% capacity retention. This work highlights the "pining effect" in preventing unfavorable slab sliding and structural deterioration, offering new insights for designing advanced ultrahigh Ni single-crystal cathodes.

Bayesian information criteria for multiple regression models: A study of robustness and comparisons

It is recommended to employ robust versions of selection criteria for variables in linear regression when extreme outliers and high leverage points present. This article investigates the robust version of the Bayesian information criterion based on the MM-estimation scale BICMM . Furthermore, the robustness properties of the proposed BICMM criterion are examined via its breakdown point, influence function, and gross-error sensitivity. Performance of the proposed criterion is compared to existing non-robust and robust Bayesian information criterion, robust Akaike’s information criterion, robust Mallows’ C p , and robust Schwarz information criterion, based on the least-trimmed squares estimator. Simulation studies and applications on real data reveal that BICMM selects more suitable models in situations where there are outliers or leverage points. Consequently, when multicollinearity exists, the proposed robust BICMM can be used to select the tuning parameter in shrinkage regression methods such as ridge and lasso regression.

The Evolution of Underwater Microelectronic Encapsulation: An Universal Marine Wearable Hydrogel

AbstractLong‐term access to undersea information is of critical importance for undersea sensing. However, the paramount challenge in marine wearable technology lies in achieving durable and stable adhesion, coupled with biocompatibility, for devices submerged in the saline conditions of the ocean. Here, a self‐healing, seawater‐resistant hydrogel is reported that exhibits robust adhesion to diverse biotic and abiotic surfaces. Remarkably, the presented hydrogel is augmented with octopus sucker‐inspired microstructures, a feature that markedly improves its capability of organism adhesion underwater. The hydrogel exhibits robust mechanical properties in water, with over 20‐fold elongation in a fully swollen state, and a mechanical healing efficiency exceeding 90% after healing for 30 min. The hydrogel is applied toward several representative undersea scenes. Specifically, the hydrogels equipped with flexible pressure sensors are reliably affixed to fish and turtles for sensing hydraulic pressure for more than 20 days, while the hydrogels featuring a compact camera are mounted on corals and crabs for constant monitoring of surroundings. Furthermore, the hydrogel is molded into a mesh structure for integrating multiple sensors, functioning as multi‐node marine wearable platforms. The underwater hydrogel, with its broad applicability, introduces an approach to real‐time undersea monitoring and non‐invasive marine life internet construction.

Insect-derived bacteria as biocontrol tool and a potent suppressor of plant pathogenic fungi in tomato cultivation

Sustainable agriculture is increasingly emphasized, focusing on microorganisms' role in maintaining soil fertility and inhibiting plant pathogens. Seeking novel sources of plant-beneficial bacteria, our study explores insects due to their established associations with plants and bacteria. The insect gut, hosting various bacteria, may hold microbes protecting against fungal infections, particularly plant pathogens. Traditional sources of plant growth-promoting bacteria are the rhizosphere and host plant tissues; however, insects serve as diverse bacterial reservoirs in the environment. This study aimed to identify insect-gut-derived bacteria with antifungal properties and cellulase enzyme production, predicting high plant tissue colonization abilities. Cellulase, crucial for breaking down cellulose, is essential for both industry and the environment. We sought to assess the potential of these bacteria as biocontrol agents against plant pathogenic fungi, with a focus on tomato plants. Bacterial isolates from insect bodies, including Lactococcus lactis, Pantoea ananatis, and Serratia liquefaciens, exhibited robust antifungal properties and cellulase activity. In vitro tests and glasshouse tests, confirmed their ability to inhibit the growth of plant-pathogenic fungi, indicating potential for biological control. Moreover, selected strains demonstrated high cellulase enzyme activity, vital for nutrient competition and rapid colonization of plant surfaces. The study introduces insect-gut-derived bacteria as promising biocontrol agents against plant pathogenic fungi. The identified strains, capable of inhibiting fungal growth and producing cellulase, offer sustainable alternatives to synthetic fungicides for protecting tomato plants. The findings advance agricultural practices by harnessing insect-associated bacteria, contributing to eco-friendly and efficient pest management strategies in modern agriculture.

The therapeutic effect of antioxidant postbiotic cocktail in colitis mice: A promising approach to alleviate oxidative stress in two high-fat and normal-diet feeding mice

It seems that postbiotics as a byproduct of fermentation of probiotic bacteria could be more effective in health benefits context. Therefore, in this study we aimed to assess the effectiveness of a novel postbiotic resulted from native probiotic Lactobacillus strains with robust antioxidant properties in ameliorating colitis in murine models fed with Normal-Diet or High Fat-Diet. Material and methodsEighty-eight strains of Lactobacillus and Bifidobacterium sourced from human feces and milk were screened for antioxidant activity. Six potent strains were selected to formulate a postbiotic cocktail, with its major compounds identified through gas chromatography. ResultsIn an animal study, mice with dextran sulphate sodium (DSS)-induced colitis that received the postbiotic cocktail showed significant improvements in phenotypical indices compared to the DSS group. Mice on both dietary regimens exhibited reduced adverse effects associated with DSS consumption, as indicated by lower Disease Activity Index (DAI) and Pathological Score metrics, along with increased intestinal mass and length(p<0.05). Additionally, mice receiving the postbiotic cocktail demonstrated elevated levels of antioxidant enzymes and anti-inflammatory cytokines(p<0.05). ConclusionThis suggests that the postbiotic not only mitigates inflammation but also enhances antioxidant defenses, particularly in those on a normal diet. Overall, these findings indicate that this novel postbiotic mixture has potential for effectively managing colitis, especially when combined with a healthy dietary regimen, while also highlighting opportunities to optimize environmental factors to enhance its antioxidant capabilities.

Fault Estimation and Tolerant Anti‐Disturbance Switching Control for Switched Systems With Its Application to Circuit Systems

ABSTRACTThis study proposes a fault estimation and tolerant anti‐disturbance switching control (ADSC) approach for the switched systems subject to the system fault and multiple disturbances. The fault dose not required to have a model. The disturbances contain the modeled unmeasurable part and the unmodeled measurable part. First, a composite switching estimator is constructed to simultaneously estimate the unavailable system state, fault and modeled disturbance. Then, by means of the estimator, a switching controller is developed to tolerant the fault and complement the modeled disturbance. Further, under the average dwell time relevant switching signals, criteria are established to ensure the fault estimation performance and robustness property for the switched systems. Finally, via implementing the presented fault estimation and tolerant ADSC scheme on a switched circuit system to regulate the charge and flux, the reasonability of the established result is verified.

Robust Cd(4,5-Imdb)-MOF for Lewis-Acid Assisted Catalysis and Selective Sensing of 2,4,6-Trinitrophenol.

Developing multifunctional metal-organic frameworks (MOFs) for effective catalysis and sensing remains a significant challenge. This study presents the synthesis of an imidazole-based angular linker, 4,4'-(1-methyl-1H-imidazole-4,5-diyl)dibenzoic acid (4,5-H2Imdb), which is used in the synthesis of the Cd(4,5-Imdb)-MOF. This MOF demonstrates robust and recyclable properties, making it suitable for solvent-free Strecker synthesis and in the detection of the secondary explosive 2,4,6-trinitrophenol (TNP) molecule, with a limit of detection (LOD) of 7.5 ppb in methanol. The material's hydrolytic stability and reusability are thoroughly evaluated. Additionally, density functional theory (DFT) calculations provide insights into the selective detection mechanism of TNP. These findings highlight the potential of Cd(4,5-Imdb)-MOF in catalysis and sensing applications.

Robust and Antifouling Composite Hydrogels Enhanced by Directional Freeze-Casting and Salting-Out for Highly Efficient Solar Evaporation.

Hydrogels have been identified as a promising material platform for solar-driven interfacial evaporation. However, designing durable hydrogel solar evaporators that can combine effective photothermal conversion, superior water transport, salt resistance, and robust mechanical properties to ensure stable and efficient evaporation remains a significant challenge. Herein, a robust and antifouling hydrogel-based solar evaporator composed of poly(vinyl alcohol), sodium alginate, and MXene is successfully constructed through directional freeze-casting and salting-out processes. The directional freeze-casting aids in forming vertically aligned, well-interconnected channels within the hydrogel that facilitate rapid upward water transfer and effective salt ion discharging, while the optimized salting-out process promotes the cross-linking of polymer chains, creating a sponge-like porous structure that enhances key mechanical properties such as high elasticity and exceptional flexibility. The developed hydrogel evaporator achieves an impressive evaporation rate of 2.53 kg m-2 h-1 with an energy efficiency of 93%, as well as excellent salt resistance and long-term evaporation stability even when desalinating high-concentration brines. These exceptional characteristics make this composite hydrogel evaporator highly suitable for practical applications in seawater desalination and wastewater purification.

The Short Warwick-Edinburgh Mental Well-being Scale (SWEMWBS): an Italian validation using confirmatory factor analysis and Rasch analysis

The present study examined the psychometric properties of the Short Warwick-Edinburgh Mental Well-being Scale (SWEMWBS). A total of 742 Italian participants (84.6% female), with a mean age of 33.08 years (SD = 12.44) took part in a cross-sectional survey study. Confirmatory factor analysis and Rasch analysis were used to examine the psychometric properties. The CFA showed that the SWEMWBS had a unidimensional structure with robust psychometric properties and showed good internal consistencies (Cronbach’s alpha 0.88; McDonald’s omega 0.91). Overall, most items showed no substantial differential item functioning in the Rasch analysis, except for Item 7, indicating that female participants reported more difficulty with this item than the male participants. The SWEMWBS was positively associated with life satisfaction and negativity associated with general psychological distress (i.e., anxiety, stress, and depression). In sum, the SWEMWBS showed robust psychometric properties capable of assessing positive aspects of mental health and well-being among Italian-speaking adults.

On Rosenbaum’s Rank-based Matching Estimator

Summary In two influential contributions, Rosenbaum (2005, 2020a) advocated for using the distances between component-wise ranks, instead of the original data values, to measure covariate similarity when constructing matching estimators of average treatment effects. While the intuitive benefits of using covariate ranks for matching estimation are apparent, there is no theoretical understanding of such procedures in the literature. We fill this gap by demonstrating that Rosenbaum’s rank-based matching estimator, when coupled with a regression adjustment, enjoys the properties of double robustness and semiparametric efficiency without the need to enforce restrictive covariate moment assumptions. Our theoretical findings further emphasize the statistical virtues of employing ranks for estimation and inference, more broadly aligning with the insights put forth by Peter Bickel in his 2004 Rietz lecture (Bickel, 2004).