Results 141 to 150 of about 30,733 (250)
Nonparametric instrumental variables estimation of a quantile regression model [PDF]
We consider nonparametric estimation of a regression function that is identified by requiring a specified quantile of the regression "error" conditional on an instrumental variable to be zero.
Joel Horowitz, Sokbae 'Simon' Lee
core
Development and validation of MethylCog, a blood DNA methylation proxy for cognition
Alzheimer's &Dementia, Volume 22, Issue 5, May 2026.Abstract INTRODUCTION Heterogeneity in cognitive ability increases with age and predicts mild cognitive impairment (MCI) and dementia, but scalable blood‐based biomarkers are lacking. We developed and validated MethylCog, a parsimonious DNA methylation (DNAm) marker of general cognitive ability (g).
Deirdre M. O'Shea +9 more
wiley +1 more source
Impact of Income on Calorie and Nutrient Intakes: A Cross-Country Analysis [PDF]
The relationship between income and nutrient intake is explored. Nonparametric, panel, and quantile regressions are used. Engle curves for calories, fat, and protein are approximately linear in logs with carbohydrate intakes exhibiting diminishing ...
Balcombe, Kelvin George +2 more
core +1 more source
Crop Science, Volume 66, Issue 3, May/June 2026.Abstract We tested the hypothesis that metaxylem phenotypes influence drought adaptation in maize (Zea mays L.) through in silico modeling and empirical studies under water deficit in controlled environments and in the field. Substantial genotypic variation for metaxylem vessel element length (MVEL) was observed. Longer MVEL was correlated with reduced
Christopher F. Strock +4 more
wiley +1 more source
The Role of Price‐Volatility Cojumps in Volatility Forecasting
Journal of Futures Markets, Volume 46, Issue 5, Page 931-951, May 2026.ABSTRACT This paper investigates whether simultaneous jumps in prices and volatility improve volatility forecasting. Using up‐to‐date high‐frequency S&P 500 and VIX data, we identify price‐volatility cojumps at the intraday granularity and construct upside, downside, and asymmetric measures.
Kefu Liao
wiley +1 more source
Nonparametric quantile regression for spatio-temporal processes
33 pages, 2 figures and accompanying supplementary ...
Deb, Soudeep +2 more
openaire +2 more sources
International Journal of Climatology, Volume 46, Issue 6, May 2026.Drought spatiotemporal propagation and direct driving variables are assessed at multiple time steps with high spatial resolution using various drought indices (SPI, SPEI and SPDI) and entropy based mutual information under an ensemble of climate change projections over Tunisia. ABSTRACT Projecting drought occurrence and spatiotemporal propagation under
Haykel Sellami
wiley +1 more source
An Ensemble Classifier for Ordinal Outcomes in High‐Dimensional Genomics Data
Pharmaceutical Statistics, Volume 25, Issue 3, May/June 2026.ABSTRACT Analysis of genomics data for predicting disease outcomes is a fast‐growing field in medical research. There often exist categorical, specifically, ordinal outcomes that need to be predicted based on genomic profiles. This has led to recent development of some high‐dimensional ordinal classification methods that can address the large ...
Heranga K. Rathnasekara, Sinjini Sikdar
wiley +1 more source
Efficient Estimation of Semiparametric Conditional Moment Models with Possibly Nonsmooth Residuals [PDF]
This paper considers semiparametric efficient estimation of conditional moment models with possibly nonsmooth residuals in unknown parametric components (theta) and unknown functions (h) of endogenous variables.
Demian Pouzo, Xiaohong Chen
core
Multi‐Level Variable Selection Using a BART‐Enhanced Mixed‐Effects Framework
Statistics in Medicine, Volume 45, Issue 10-12, May 2026.ABSTRACT Selecting important individual‐ and cluster‐level predictors has become increasingly critical in healthcare research, where data often exhibit hierarchical structures due to collection from multiple clusters. Mixed‐effects models, which account for within‐cluster correlation and between‐cluster heterogeneity, are a natural approach for ...
Keming Zhang +5 more
wiley +1 more source