Rank: 941 based on 149 downloads (last 30 days) and 3 files submitted
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James Conder

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Southern Illinois University
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Files Posted by James Conder View all
Updated   File Tags Downloads
(last 30 days)
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24 Sep 2014 Screenshot Gaussian smoothing filter Function to smooth a time series using a Gaussian filter. Author: James Conder gaussian filter, signal processing, smoothing 93 3
  • 4.0
4.0 | 2 ratings
14 Feb 2014 Screenshot Logistic curve fit Fit a time series to a best-fitting logistic function. Author: James Conder logistic, curvefitting 43 6
16 May 2013 F-Test Test whether addition of model parameters is warranted by improvement of data misfits. Author: James Conder statistics, ftest 13 0
  • 5.0
5.0 | 1 rating
Comments and Ratings by James Conder View all
Updated File Comments Rating
04 Sep 2014 Gaussian smoothing filter Function to smooth a time series using a Gaussian filter. Author: James Conder

jon, thanks for the feedback. I originally wrote the function for a non-uniformly spaced time vector, which conv would not handle correctly. That said, I expect most uses of this function will be for uniformly spaced time vectors, where your criticism is exactly right.

I uploaded an update that will look to do the convolution unless the spacing is variable, in which case it will use the (ugly) loop.

12 Feb 2014 Logistic curve fit Fit a time series to a best-fitting logistic function. Author: James Conder

Andrew, I spent some time looking at it, and think I have fixed the problem. I just uploaded a newer version. Once it is up, please try your dataset on it and let me know how it goes.

28 May 2013 Logistic curve fit Fit a time series to a best-fitting logistic function. Author: James Conder

Hi Darren,

Sorry about the plotting calls. I realized that I forgot to remove them just after resubmitting. I guess the follow up submission with those removed is still moving though the system.

Good catch on reversing t. It is one of those bugs introduced when addressing a different problem. I'll fix that bug and put a test example in the help comments in new submission later today.

23 May 2013 Logistic curve fit Fit a time series to a best-fitting logistic function. Author: James Conder

Thanks for the feedback, Darren. I've made a fix based on your idea of rescaling the vector internally, and submitted an update. It isn't completely obvious to me why Qpre goes to the mean of Q for some scalings of t. In any case, I hope my fix is general and not limited to your special case. Keep me posted.

16 May 2013 Fit Logistic Curve to a Data Set This is a Matlab GUI, that will try to fit a logistic function to a given set of data. Author: Varuna De Silva

I suspect the problem Rita and Michael were having is that their data describes a decreasing logistic and the program is set up to do an increasing logistic. I just uploaded a non-GUI fit_logistic function and at first it failed with Rita's data, too. Fortunately, it is an easy fix by making the time series negative.

Comments and Ratings on James Conder's Files View all
Updated File Comment by Comments Rating
04 Sep 2014 Gaussian smoothing filter Function to smooth a time series using a Gaussian filter. Author: James Conder James Conder

jon, thanks for the feedback. I originally wrote the function for a non-uniformly spaced time vector, which conv would not handle correctly. That said, I expect most uses of this function will be for uniformly spaced time vectors, where your criticism is exactly right.

I uploaded an update that will look to do the convolution unless the spacing is variable, in which case it will use the (ugly) loop.

03 Sep 2014 Gaussian smoothing filter Function to smooth a time series using a Gaussian filter. Author: James Conder jon erickson

Works fine, but implementation is could be improved/sped up by using conv(...) instead of a for loop to compute filtered waveform

06 Aug 2014 Gaussian smoothing filter Function to smooth a time series using a Gaussian filter. Author: James Conder Philippe

Great! Does what it advertise. Thanks for this submission.

12 Feb 2014 Logistic curve fit Fit a time series to a best-fitting logistic function. Author: James Conder James Conder

Andrew, I spent some time looking at it, and think I have fixed the problem. I just uploaded a newer version. Once it is up, please try your dataset on it and let me know how it goes.

10 Feb 2014 Logistic curve fit Fit a time series to a best-fitting logistic function. Author: James Conder Andrew

James,

Great function, thank you. I too have the issue with outputting a constant value for Qpre, and, as with Darren, changing the scaling of the value for t fixes this. My t values scale between 0 and 1 in steps of 0.001.

Many thanks

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