FACT: FAQ

1. How to use ROI waveform to do correlation anaylsis?

2. How to use KCN/FCM cluster waveform to do correlation analysis?

3. How to use known paradigm to help to select KCN/FCM clusters?

4. Why FACT crashed when running KCN analysis?

5. FACT displayed big font so that options can't be selected.

1. How to use ROI waveform to do correlation anaylsis?

You can use an ROI waveform or any waveform you generated by Matlab or so as a reference waveform in correlation analysis. To use an ROI as a reference waveform, you can use the following procedure:

First, we save the ROI waveform we want:

1) select an ROI in the main window.

2) click "Show ROI" to display the waveform.

3) click "Save Value" on the right-hand-side of the Show ROI window.

4) Choose a desired format, e.g., TXT. (Note: using TXT can let you read it in MS Excel.)

5) Input a filename and click "OK".

Next, use the saved waveform in correlation analysis:

6) Choose "Analysis"-->"Correlation" on the main window.

7) On the left-hand-side of the Correlation Analysis window, change "Reference Waveform" to "User Define".

8) Input the path and filename, and select the correct waveform format, e.g., TXT.

9) Go to the right-hand-side of the Correlation Analysis window to set a proper threshold and click "Apply All".

2. How to use KCN/FCM cluster waveform to do correlation analysis?

An easy way to use KCN/FCM cluster waveform as a reference in correlation analysis is:

1) Display the KCN or FCM cluster waveform.

2) Select the waveform you want to do correlation analysis. (Note: you can only select one waveform at a time.)

3) On the menu bar, select the "Show"-->"Map by CorrCoef".

4) The correlation analysis window will show up and you can set a desired threshold. Then click on "Apply All".

3. How to use known paradigm to help to select KCN/FCM clusters?

1) Setup or load a paradigm.

2) Display the KCN or FCM cluster waveform.

3) On the menu bar, select "Show"-->"Show Paradigm". Then the paradigm and the cluster waveform will be shown together.

4) Furthermore, you can calculate the correlation between the cluster waveform and the paradigm by select "Sort"-->"by CorrCoef".

4. Why FACT crashed when running KCN analysis?

One possible cause of this problem is that the input data contained some pixels that were too noisy and made divide-by-zero or overflow problem during the processing. The latest version of FACT had added some mechanism to try to avoid this condition, or at least giving some error message instead of crash. If you saw the related message, please try to eliminate these pixels by smoothing or proper setting of background threshold.

4. FACT displayed big font so that options can't be selected.

This issue typically happens when you run FACT from remote, especially thru VNC. To solve this, run FACT by forcing it to use small font size with this option:

fact -Wx small

Last Update: 2004/02/25