Results 41 to 50 of about 6,035,490 (336)
Bias due to participant overlap in two‐sample Mendelian randomization
Genetic Epidemiology, 2016 Mendelian randomization analyses are often performed using summarized data. The causal estimate from a one‐sample analysis (in which data are taken from a single data source) with weak instrumental variables is biased in the direction of the ...
S. Burgess, N. Davies, S. Thompson
semanticscholar +1 more source
Unbiased Analysis of Item-Specific Multi-Voxel Activation Patterns Across Learning
Frontiers in Neuroscience, 2018 Recent work has highlighted that multi-voxel pattern analysis (MVPA) can be severely biased when BOLD response estimation involves systematic imbalance in model regressor correlations.
Hannes Ruge +5 more
doaj +1 more source
Sequential monitoring with conditional randomization tests
, 2012 Sequential monitoring in clinical trials is often employed to allow for early stopping and other interim decisions, while maintaining the type I error rate.
Plamadeala, Victoria +1 more
core +1 more source
BMC Medical Research Methodology, 2016 Background Randomization procedure in randomized controlled trials (RCTs) permits an unbiased estimation of causal effects. However, in clinical practice, differential compliance between arms may cause a strong violation of randomization balance and ...
Annalisa Pezzi +4 more
doaj +1 more source
Conditioning on parental mating types can reduce necessary assumptions for Mendelian randomization
Frontiers in Genetics, 2023 Mendelian randomization (MR) has become a common tool used in epidemiological studies. However, when confounding variables are correlated with the instrumental variable (in this case, a genetic/variant/marker), the estimation can remain biased even with ...
Keisuke Ejima +8 more
doaj +1 more source
A Sim-Learnheuristic for the Team Orienteering Problem: Applications to Unmanned Aerial Vehicles
AlgorithmsIn this paper, we introduce a novel sim-learnheuristic method designed to address the team orienteering problem (TOP) with a particular focus on its application in the context of unmanned aerial vehicles (UAVs).
Mohammad Peyman +3 more
doaj +1 more source
Efficient randomized-adaptive designs
, 2009 Response-adaptive randomization has recently attracted a lot of attention in the literature. In this paper, we propose a new and simple family of response-adaptive randomization procedures that attain the Cramer--Rao lower bounds on the allocation ...
He, Xuming, Hu, Feifang, Zhang, Li-Xin
core +1 more source
Economics and Human Biology, 2014 Highlights • We model potential biases that may arise in Mendelian randomization analysis.• Genetic variants should robustly associate with exposures in independent samples.• If not, Mendelian randomization can suggest causality despite no true ...
Amy E Taylor +5 more
semanticscholar +1 more source
American options under stochastic volatility: control variates, maturity randomization & multiscale asymptotics [PDF]
, 2015 American options are actively traded worldwide on exchanges, thus making their accurate and efficient pricing an important problem. As most financial markets exhibit randomly varying volatility, in this paper we introduce an approximation of American ...
Agarwal, Ankush +2 more
core +1 more source
Fragment formation in biased random walks [PDF]
Journal of Statistical Mechanics: Theory and Experiment, 2008 6 pages, 2 ...
openaire +3 more sources