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Activity Number:
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142
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Type:
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Contributed
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Date/Time:
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Monday, August 7, 2006 : 10:30 AM to 12:20 PM
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Sponsor:
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Section on Nonparametric Statistics
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| Abstract - #306214 |
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Title:
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A Comparative Study of Stage-1 and Stage-2 Semiparametric Estimation of Hemodynamic Response Function for fMRI Data
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Author(s):
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Chunming Zhang*+ and Yuan Jiang and Tao Yu
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Companies:
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University of Wisconsin-Madison and University of Wisconsin-Madison and University of Wisconsin-Madison
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Address:
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1300 University Ave., Madison, WI, 53706,
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Keywords:
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false discovery rate ; multiple comparison ; semiparametric test ; stimuli ; time resolution
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Abstract:
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The standard tool for analyzing functional magnetic resonance imaging (fMRI) data is some variant of the linear model, which is restrictive in modeling assumptions. We develop a semiparametric approach, based on the cubic smoothing splines, to obtain statistically more efficient estimates of the hemodynamic response function (HRF) associated with fMRI experiments. The hypothesis testing of HRF is conducted to identify regions of the brain which are activated when a subject performs a particular task. Furthermore, we compare stage-1 and stage-2 semiparametric estimates of HRF in significance tests for detecting the activated brain regions. Our simulation studies demonstrate that the stage-1 estimates combined with a bias correction procedure perform best in detecting the activated brain regions. We illustrate this method using a real fMRI dataset and compare with popular methods.
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