Materials for “ Evaluating independent component analyses with an application to resting - state fMRI
نویسندگان
چکیده
We are not aware of functions or packages in R that implement the Infomax algorithm (Bell and Sejnowski 1995). We offer an alternative to Matlab code (http://cnl.salk. edu/~tewon/ICA/code.html), but with a few modifications that decrease computation time. First, we use the full data (the so-called offline algorithm) in each iteration rather than an online algorithm with batches. Secondly, we use an adaptive method to choose the step size (based upon Bernaards and Jennrich 2005), which speeds up convergence. We also omitted the bias term (intercept) included in the original formulation because we centered our data. R code implementing the Infomax algorithm and example simulations are available in and in the Supplementary Materials.
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