Search found 26 matches

by EliGC
17 Sep 2010, 17:57
Forum: BCI Systems - Signal Processing
Topic: Coefficient of Determination
Replies: 1
Views: 2159

Coefficient of Determination

Good Morning, I Have two main questions about r^2: 1. If I am doing a P300 experiment with two subjects, and I found that one has a bigger value of r^2 than the other one, what this exactly means? That one can evoked stronger the P300? 2. In the dissertation that is posted here to find more informat...
by EliGC
07 Sep 2010, 10:49
Forum: BCI Systems - Signal Processing
Topic: r2 values
Replies: 21
Views: 13458

confussion about r^2

Good Morning, I Have two main questions about r^2: 1. If I am doing a P300 experiment with two subjects, and I found that one has a bigger value of r^2 than the other one, what this exactly means? That one can evoked stronger the P300? 2. In the dissertation that is posted here to find more informat...
by EliGC
15 Jul 2010, 15:46
Forum: BCI Systems - Brain Signals
Topic: Amplification with USBamp, real value in microV
Replies: 3
Views: 3514

Mr. Juergen Thank you for your answer :) . I am sorry but I am still having the same dude. :? Because one thing is the SourceChGain that you can configure for g.USBamp, but the other thing is the SourceChGain that you can configure in BCI2000. My point is, the SourceChGain that is apply in BCI2000 a...
by EliGC
14 Jul 2010, 12:30
Forum: BCI Systems - Brain Signals
Topic: Amplification with USBamp, real value in microV
Replies: 3
Views: 3514

Amplification with USBamp, real value in microV

Good Afternoon, I am using the USBamp with no amplification (gain per channnel=1), BCI2000 by default has as SourceChGain = 0.033. My question is, if I am getting a value of 1 (A/D units) when I analyze my signals in Matlab, then the real value of them will be: 1*0.033=0.033 microVolts? Thank you so...
by EliGC
02 Jun 2010, 09:25
Forum: BCI Systems - Brain Signals
Topic: signals and noise
Replies: 2
Views: 3110

Thank you so much for your answer. We are using USB.amp (g.tec) and we always check the impedances (and they are below 5KOhm), also we always use abrasive and conductive gel. For ground we are using Fpz and as reference, right ear lobe. We have been working with P300 since two years ago, and our sys...
by EliGC
28 May 2010, 12:58
Forum: BCI Systems - Brain Signals
Topic: signals and noise
Replies: 2
Views: 3110

signals and noise

Hello everyone!! :D I am working in sensorimotor rhythm BCI with this software, but I am not sure if my signals are adcquiring good or if I am still having lot of noise there. I don´t have enough experience to say if my signals are clean, respect the noise, or not. Can you help me with this? For the...
by EliGC
11 May 2010, 11:52
Forum: BCI Systems - Signal Processing
Topic: r2 values
Replies: 21
Views: 13458

question about r^2

Hello, I don´t know if you can answer my question but I will try to explain you what is my objective with the r^2. :oops: I am trying to make a time-frequency analysis for my data during a sensorimotor rhythm experiment. The point is that if I want to be sure that I found a desynchronization or sync...
by EliGC
10 May 2010, 09:23
Forum: BCI Systems - Signal Processing
Topic: r2 values
Replies: 21
Views: 13458

THANK YOU SO MUCH!! :D
by EliGC
07 May 2010, 09:21
Forum: BCI Systems - Signal Processing
Topic: r2 values
Replies: 21
Views: 13458

r^2 definition

Hello!
Can somebody help me with the thesis document where r^2 is described better?

The links that are posted here are not working any more.

Thank you so much :P
by EliGC
06 Apr 2010, 15:46
Forum: BCI Systems - Brain Signals
Topic: three mental tasks with mu-rhythm
Replies: 10
Views: 8616

Trying to find changes in mu and betha rhythms SM task

Hello. First of all, sorry about my long post. :? Since two weeks a go, I started with the mu tutorial, implementing the same 4 task stimulation that is showed there. :D (We already had experimented during two years with P300, but sensorimotor rhythms are new for us :oops: ). I have a couple of ques...
by EliGC
24 Mar 2010, 17:11
Forum: Known Issues
Topic: Using BCI200 with pic18f
Replies: 1
Views: 1674

Using BCI200 with pic18f

Hello, im trying to connect bci200 with a hommemade
electroencephalograph using usb connection with a microcontroller pic18f2550. i dont know how to get a driver for my device to be recognized by bci 2000. if anyone has an answer that would be very helpful for me
by EliGC
05 Feb 2010, 11:20
Forum: Known Issues
Topic: how to install bci2000
Replies: 7
Views: 3827

I´m sorry, I am trying to install the BCI2000 and I have the same error as Faisal.

BCI2000setup.exe is not supported

I am riding on windows windows xp.

Thanks,
by EliGC
05 Feb 2010, 10:16
Forum: Known Issues
Topic: Error in Matlab with offline analysis
Replies: 3
Views: 2004

When I try to execute load_bcidat.m Matlab says: - C:\...000\tools\OfflineAnalysis\load_bcidat.m is not found in the current directory or on the MATLAB path. But the function load_bcidat, as I told you is in the same directory of the offline analysis GUI. The other thing is that when I tried to use ...
by EliGC
01 Feb 2010, 16:12
Forum: Known Issues
Topic: Error in Matlab with offline analysis
Replies: 3
Views: 2004

Error in Matlab with offline analysis

Hello!! I have problems trying to read the data with the offline GUI. I have everything in the save directory, including the function load_bci and the .data files, but I´ve continued having the same error:; Error using ==> load_bcidat Out of memory when reading file name. Error in ==> OfflineAnalysi...
by EliGC
27 Oct 2008, 21:46
Forum: Data Analysis
Topic: SWLDA
Replies: 1
Views: 2535

SWLDA

HI everyone, my name is Eliana, i´m from Colombia- South America. We are developing a BCI Lab (is our final work of the career), and we made an EEG, and it works perfect with the BCI2000. But we want to make an algorithm based LDA, SWLDA. We are trying to understand the P300GUI, specially the SWLDA ...