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Activity Number:
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103
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Type:
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Contributed
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Date/Time:
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Monday, August 7, 2006 : 8:30 AM to 10:20 AM
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Sponsor:
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Biometrics Section
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| Abstract - #305428 |
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Title:
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The LASSO Method for Variable Selection for Right-Censored Data
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Author(s):
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Lili Yu*+ and Dennis K. Pearl
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Companies:
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The Ohio State University and The Ohio State University
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Address:
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Trumbull Court, Columbus, 43210,
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Keywords:
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sieve likelihood ; LASSO ; model selection ; right censored data
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Abstract:
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Tibshirani proposed a variation of the "lasso" method that was to minimize the log partial likelihood subject to the sum of the absolute values of the parameters being bounded by a constant in Cox's proportional hazards model. Due to the nature of this constraint, it shrinks coefficients and produces coefficients that are exactly zero. We apply this method to a class of semiparametric models (linear transformation models) in which the response variable is right-censored and the error is symmetric at zero but its distribution is unknown. We propose to use sieve-likelihood method to calculate the log likelihood and the parameters simultaneously. Simulations indicate using sieve-likelihood to calculate the lasso criteria in this setting can pick approximately the correct number of zero coefficients.
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