Hi Giovanna,
> On Aug 3, 2011, at 6:00 AM, IMAGEJ automatic digest system wrote:
>
>>
>> ------------------------------
>>
>> Date: Tue, 2 Aug 2011 09:59:35 +0200
>> From: Giovanna delVecchio <
[hidden email]>
>> Subject: Re: question regarding Colocalization Threshold in Fiji - Coloc2
>>
>>
>> Can you send me the images for testing?
>>>
>>> Do you really mean negative or is this a mis-speak? The theoretical
>> range
>>> of p is 0 to 1.0
>>
>> no, the range for Pearsons r is -1 to +1
>>
>>> Thus, values lower than zero suggest that the code is
>>> broken or improperly applied.
>>
>> negative values are certainly possible,
>> but perhaps the issue here is that there is another related problem...
>>
>> let me have the images and i will investigate...
>>> Sorry the p values are Ok actually.My mistake:I mis-spelled..
>> I meant the r(rand) not the p values.
>
> My problem now is just that I can´t use coloc2 and I can´t
> rely too much on Colocalization threshold plugin that actually
> provides
> too low thresholds in some cases..
The thresholds that coloc2 and the old colcalization threshold plugin
give should be close to identical.
its the same method, but slightly diffrent implementation.
if you get very different thresholds ,
send me images so i can find out why.
The Costes autothreshold algorithm sets the thresholds
not where you might put thrm by eye subjectively,
but ojjectively according to a simple statistical criterion:
below thresholds Pearsons r is approx 0
If you dont like those thresholds, then the algorithm is asking
a different question than you want it to.
the selection of the region of interest is critical.
As is correct zero offset and limiting signal noise.
D
>
>>
>> did you use a region of interest?
>>
>>
>> cheers
>>
>> Dan
>>
>>>
>>> Rob
>>>
>>>
>>> ------------------------------------------
>>> Robert W. Baer, Ph.D.
>>> Professor of Physiology
>>> Kirksville College of Osteopathic Medicine
>>> A. T. Still University of Health Sciences
>>> 800 W. Jefferson St.
>>> Kirksville, MO 63501
>>> 660-626-2322
>>> FAX 660-626-2965
Dr. Daniel James White BSc. (Hons.) PhD
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