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A comparison study of nonparametric imputation methods

Jianhui Ning, Philip E. Cheng
2010 Statistics and computing  
Empirical studies show that the nearest neighbor imputation method is most effective among these imputation methods for estimating a finite population mean and for classifying the species of the iris flower  ...  Two common approaches to imputing the missing values are the nonparametric regression weighting method and the Horvitz-Thompson (HT) inverse weighting approach.  ...  this comparison study.  ... 
doi:10.1007/s11222-010-9223-y fatcat:yicehjcltffenehecrizw4do54

Nonparametric autocovariance estimation from censored time series by Gaussian imputation

Jung Wook Park, Marc G. Genton, Sujit K. Ghosh
2009 Journal of nonparametric statistics (Print)  
Comparison of nonparametric and parametric imputations In general, it is well known that a nonparametric estimate loses some efficiency in comparison to a parametric estimate when a correctly specified  ...  Section 2 describes the nonparametric estimation of the autocovariance function and its implementation within the imputation method. Section 3 reports the results of a simulation study.  ... 
doi:10.1080/10485250802570964 pmid:20072705 pmcid:PMC2804993 fatcat:soetrvoiabbg7eg2jr5xow3oee

Nonparametric multiple imputation for receiver operating characteristics analysis when some biomarker values are missing at random

Qi Long, Xiaoxi Zhang, Chiu-Hsieh Hsu
2011 Statistics in Medicine  
The proposed imputation methods provide a platform for a full range of ROC analysis, and hence are more flexible than existing methods that primarily focus on estimating the area under the ROC curve (AUC  ...  While a direct application of standard nonparametric imputation is robust to model misspecification, its finite sample performance suffers from curse of dimensionality as the number of auxiliary variables  ...  While we focus on the K-NN nonparametric imputation, other nonparametric methods can be readily adopted for imputation, say, kernel methods [22] .  ... 
doi:10.1002/sim.4338 pmid:22025311 pmcid:PMC3205437 fatcat:cxefzryqtvfonphnlownbnanhy

Investigation of Missing Responses in Q-Matrix Validation

Shenghai Dai, Dubravka Svetina, Cong Chen
2018 Applied Psychological Measurement  
Number of attributes and items have an impact on performance of both methods as well. Results of a real data example are also discussed in the study.  ...  Results of the simulation study show that both validation methods perform better when missing responses are imputed using EM imputation or logistic regression instead of being treated as incorrect and  ...  Estimates of both validation methods for complete data (i.e., MR = 0%) were used as the baseline for comparison. Missing imputation approaches.  ... 
doi:10.1177/0146621618762742 pmid:30559573 pmcid:PMC6291893 fatcat:y4p4rut33bga3ae6abyligmb4a

Nonparametric comparison of two survival functions with dependent censoring via nonparametric multiple imputation

Chiu-Hsieh Hsu, Jeremy M. G. Taylor
2009 Statistics in Medicine  
Based on the imputing risk set, a nonparametric multiple imputation method, Kaplan-Meier imputation, is used to impute a future event or censoring time for each censored observation.  ...  We extend our previous work on estimation using auxiliary variables to adjust for dependent censoring via multiple imputation, to the comparison of two survival distributions.  ...  The simulation study shows that the use of this nonparametric multiple imputation method can lead to a valid log-rank or Wilcoxon test even in the presence of dependent censoring.  ... 
doi:10.1002/sim.3480 pmid:18991250 fatcat:d3aprvbj2nfa5f7twz4w6knvxy

Kernel smoothing as an imputation technique for right-censored data

Dursun AYDIN, Ersin YILMAZ
2020 Eskişehir Technical University Journal of Science and Technology A - Applied Sciences and Engineering  
A simulation study is conducted to show the benefits of the method, and it is also compared with Ordinary Least Squares (OLS) based imputation, which is one of the widely used imputation methods and works  ...  This study introduces the kernel smoothing method as an imputation method that takes into account the structure of the data and the individual effects of the accessible data points with kernel weights.  ...  A simulation study is conducted to show the benefits of the method, and it is also compared with OLS based imputation method, which is one of the widely used imputation methods and studies similar to the  ... 
doi:10.18038/estubtda.817979 fatcat:72c7hbwzwndprhzejtimg6hpda

Nonparametric imputation method for nonresponse in surveys [article]

Caren Hasler, Radu V. Craiu
2017 arXiv   pre-print
A new imputation method for item nonresponse in surveys is proposed based on a nonparametric estimation of the functional dependence between the variable of interest and the auxiliary variables.  ...  Many imputation methods are based on statistical models that assume that the variable of interest is a noisy observation of a function of the auxiliary variables or covariates.  ...  This research was supported by the Swiss National Science Foundation, project number P1NEP2 151904 (CH) and the Natural Science and Engineering Research Council of Canada (RVC).  ... 
arXiv:1603.05068v2 fatcat:mbmx5oiymfdfvakb2qoe4jnpui

AN EFFECTIVE TECHNIQUE OF MULTIPLE IMPUTATION IN NONPARAMETRIC QUANTILE REGRESSION

Hu
2014 Journal of Mathematics and Statistics  
In this study, we consider the nonparametric quantile regression model with the covariates Missing at Random (MAR).  ...  We propose an effective and accurate two-stage multiple imputation method for the model based on the quantile regression, which consists of initial imputation in the first stage and multiple imputation  ...  The work was supported by the Fundamental Research Funds for the Central Universities and the Research Funds of Renmin University of China (Grant No. 10XNL018).  ... 
doi:10.3844/jmssp.2014.30.44 fatcat:iu2o4whxzjgfvl2ihms3vmg5sy

TIGAR: An Improved Bayesian Tool for Transcriptomic Data Imputation Enhances Gene Mapping of Complex Traits

Sini Nagpal, Xiaoran Meng, Michael P. Epstein, Lam C. Tsoi, Matthew Patrick, Greg Gibson, Philip L. De Jager, David A. Bennett, Aliza P. Wingo, Thomas S. Wingo, Jingjing Yang
2019 American Journal of Human Genetics  
Therefore, to improve on this, we employ a nonparametric Bayesian method that was originally proposed for genetic prediction of complex traits, which assumes a data-driven nonparametric prior for cis-eQTL  ...  The nonparametric Bayesian method is flexible and general because it includes both of the parametric imputation models used by PrediXcan and FUSION as special cases.  ...  ROS/MAP study data were provided by the Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago, IL.  ... 
doi:10.1016/j.ajhg.2019.05.018 pmid:31230719 pmcid:PMC6698804 fatcat:tp4ugbbt45eg5cbekl6xwlfcje

The Utility of Nonparametric Transformations for Imputation of Survey Data

Michael W. Robbins
2014 Journal of Official Statistics  
., they may be easily applied in conjunction with a wide array of imputation techniques), the proposed methodology is applied here with an algorithm for imputation in the USDA's Agricultural Resource Management  ...  Missing values present a prevalent problem in the analysis of establishment survey data.  ...  Further, the nonparametric transformations result in imputations that appear to adequately preserve the quantities studied here (though there may be evidence of a moderate decrease in the variance of P784  ... 
doi:10.2478/jos-2014-0043 fatcat:r5bc73l7rrhb5becihot7yveyy

Imputation Using the Singular Value Decomposition: Variants of Existing Methods, Proposed and Assessed

Sergio ArciniegArciniegas-Alarconas-Alarcon, Marisol Garcıa-Pena, Wojtek Janusz Krzanowski
2020 International Journal of Innovative Computing, Information and Control  
The aim of this study is to present new variants of the basic method and to determine which iterative scheme produces the higher quality imputations.  ...  For this a simulation study was performed, and from incomplete matrices the quality of the imputations was assessed by estimating their uncertainty and by other criteria such as variance, bias and mean  ...  The authors of this paper acknowledge the High Performance Computing Center -ZINE of Pontificia Universidad Javeriana for assistance during the simulation study.  ... 
doi:10.24507/ijicic.16.05.1681 fatcat:37zmgym4o5butopkkgdupcbjje

Estimation of Right-Censored Data with Partially Linear Models: A Comparison for Different Censorship Solution Methods

Yilmaz E
2019 Insights in Biomedicine  
In this paper, to handle the right-censored data which is the most common kind of censored data, three different solution methods are introduced.  ...  Therefore, it is hard modelling and analyzing datasets accurately especially in medical and clinical studies.  ...  kNN imputation method: Imputation is a class of methods that focuses to fill the censored observations with estimated ones.  ... 
doi:10.36648/2572-5610.4.1.55 fatcat:nk4oyrcilrbp5kqll6ngj4nvta

Estimating individual tree growth with nonparametric methods

S Sironen, A Kangas, M Maltamo, J Kangas
2003 Canadian Journal of Forest Research  
or underestimates Examination of different non-parametric imputation methods to reduce regional biases in growth estimates Comparison of localized estimates to estimates obtained with nonspatial imputation  ...  • Local non-parametric growth estimates for Kuusamo in Finnish Lapland • Localization of growth estimates using non-parametric imputation methodsComparison of different non-parametric growth imputation  ... 
doi:10.1139/x02-162 fatcat:7qc462wcsveonlnod5vymx36zu

Nonparametric spectral density estimation with missing observations

Thomas C. M. Lee, Zhengyuan Zhu
2009 2009 IEEE International Conference on Acoustics, Speech and Signal Processing  
The practical performance of the method is illustrated by a simulation study.  ...  In this paper this principle is applied to develop a new method for nonparametric spectrum estimation with missing data.  ...  SIMULATION STUDY A simulation study was conducted to evaluate the practical performance of the MCSC-Algorithm.  ... 
doi:10.1109/icassp.2009.4960265 dblp:conf/icassp/LeeZ09 fatcat:sqk242eqqbfmlnnxzvt5e4t4ke

Variance estimation when donor imputation is used to fill in missing values

Jean-François Beaumont, Cynthia Bocci
2009 Canadian journal of statistics  
We evaluate its performance in a simulation study when nearest-neighbour imputation is used.  ...  Our variance estimator is valid irrespective of the magnitude of the sampling fractions and the complexity of the donor imputation method.  ...  k μ and 2 k σ is clearly superior to Table 2 : 2 Comparison of variance estimation methods when k σ are estimated nonparametrically. k μ and 2 RB in % RRMSE in % Method LIN y NLIN  ... 
doi:10.1002/cjs.10019 fatcat:msut4kpi5vf55ilqr3rev2hxdu
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