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arXiv · 1401.1631

Maximin and maximin-efficient event-related fMRI designs under a nonlinear model

Ming-Hung Kao·Dibyen Majumdar·Abhyuday Mandal·John Stufken
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Abstract

Previous studies on event-related functional magnetic resonance imaging experimental designs are primarily based on linear models, in which a known shape of the hemodynamic response function (HRF) is assumed. However, the HRF shape is usually uncertain at the design stage. To address this issue, we consider a nonlinear model to accommodate a wide spectrum of feasible HRF shapes, and propose efficient approaches for obtaining maximin and maximin-efficient designs. Our approaches involve a reduction in the parameter space and a search algorithm that helps to efficiently search over a restricted class of designs for good designs. The obtained designs are compared with traditional designs widely used in practice. We also demonstrate the usefulness of our approaches via a motivating example.

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Ming-Hung Kao, Dibyen Majumdar, Abhyuday Mandal, John Stufken. 2014-01-08. Maximin and maximin-efficient event-related fMRI designs under a nonlinear model. https://doi.org/10.1214/13-aoas658

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