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. Author manuscript; available in PMC: 2015 Apr 1.
Published in final edited form as: Neuroimage. 2013 Dec 16;89:314–330. doi: 10.1016/j.neuroimage.2013.12.013

Table 4.

Reliability of the proposed optimization method using a single data set

data set used for estimation data set used for validation μ a1 a2 a3 a4 a5 a6 α MSE
TR 700 TR 800 6.1 0.0934 2.0061 3.0154 0.0546 13.9663 16.2603 21.2708 0.010
TR 1600 TR 1700 4.8 0.0776 2.0115 3.5521 0.0427 14.8203 16.0985 20.0637 0.134
TR 2500 TR 2600 7.2 0.0977 2.0252 2.7860 0.0588 13.4378 16.4564 22.1770 0.0004
data1 data2 7.0 0.0984 2.0208 2.8143 0.0584 13.4949 16.2035 21.8294 0

Note: Rows 1 to 3 list the estimated parameters {a1 a2, a3, a4, a5, a6, α} of the cardiac response function for subject #1 from a single data set for estimation (see first column) and another single data set for validation (see second column). The last row contains the parameters for the full run using datal and data2 (see Fig.1, Table 2). The third column lists the optimum curvature μ=030sd2hC(t)dt2dt where the minimum of the objective function occurred using the validation data set. The final column list the mean-squared error (MSE) of each estimated cardiac response function to the optimized cardiac response function using all available fMRI data as listed for subject #1 in the last row and Table 2.