You're getting very low VRFs because of the sub-TR estimation (TR=1.5, but TER=0.5), so you reduce your power to about 1/3. This is not a problem unless you analyze your data using an FIR. If you assume a shape, then the power will come back. doug
On 05/15/2012 11:41 AM, Andrew Valdespino wrote:
(1) Version: optseq2.c,v 2.21.2.1
(2) Computer operating system: Mac OS X Version 10.7.3
(3) Command line: optseq2 --ntp 230 --tr 1.5 --psdwin 0 24 0.5 --ev go 7 36 --ev nogo 7 12 --nkeep 4 --o gonogo --nsearch 1000
(4) Description of the problem: This is in reference to a go/no-go paradigm. I am getting very low Eff and VRFAvg values. Is this an issue/ is common with go/no-go paradigms? If this is an issue, any recommendations for appropriate modifications. A trial in my experiment involves a countdown (duration 2 seconds) followed by the event of interest (0.5 seconds) followed by a blank screen (3.5 seconds). I set dPSD at 0.5 because this number is divisible by both the --tr and trial length (7 seconds).
(5) Log and/or summary files:
Searched 1000 iterations for 0.002500 hours Rate: 111.111 iterations per second INFO: 211/1000 schedules were ill-conditioned Number of iterations since last substitution 310 Cost Avg/Std: 0.0105840 0.0060667 Max Eff Encountered: 0.0154867 Max VRFAvg Encountered: 1.6717 Eff of Nominal Ideal XtX: 0.177183
Rank Cost ZCost NthIter Eff CB1Err VRFAvg VRFStd VRFMin VRFMax VRFRng IXtXErr 1 0.0155 0.808 597 0.015 0.157407 1.67 0.61 0.80 4.13 3.33 4723.04 2 0.0150 0.732 218 0.015 0.009259 1.58 0.50 0.87 3.03 2.15 4749.02 3 0.0149 0.708 82 0.015 0.009259 1.54 0.46 0.91 3.15 2.24 4882.85 4 0.0148 0.703 539 0.015 0.175926 1.56 0.52 0.94 3.86 2.91 4752.15 ____________
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