[astro] Re: bug in likelihood estimation

[Malik Magdon-Ismail]

Hi,

I still say that the first order of business should be to test the faulty 
points locally to see if that behavior reproduces.

-Malik

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Have Faith in Probability

Malik Magdon-Ismail
Associate Professor of Computer Science
Rensselaer Polytechnic Institute (RPI)

  Office: Rm 312 Lally           mail:   Rm 207, Lally Building,
  email:  magdon at cs.rpi.edu              CS Department, RPI,
  tel:    518-276-4857                   110 8th Street,
  fax:    518-276-4033                   Troy, NY 12180-3590.
  web:    http://www.cs.rpi.edu/~magdon
  key:    http://www.cs.rpi.edu/~magdon/MalikMagdon-Ismail.PublicKey.asc
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On Wed, 21 Jan 2009, Travis Desell wrote:

> An update on this situation.  Some of our users using their own compiled apps 
> have found that they're not getting credit for bad results which only happens 
> when the application checkpoints.  This could be causing the bad results, so 
> I'm going to look into the checkpointing code and see if i can recreate bad 
> results with it.
>
> --Travis
>
> Travis Desell wrote:
>> It would be in all the other ones as well.  Having the results only be from 
>> our app at least shows that the bug is in our code (and not someone elses 
>> version).
>> 
>> Malik Magdon-Ismail wrote:
>>> hi,
>>> 
>>> In that case, how can there be a bug in that application and not in all 
>>> the others?
>>> 
>>> -Malik
>>> 
>>> -------------------------------------------------------------------------- 
>>> Have Faith in Probability
>>> 
>>> Malik Magdon-Ismail
>>> Associate Professor of Computer Science
>>> Rensselaer Polytechnic Institute (RPI)
>>> 
>>>  Office: Rm 312 Lally           mail:   Rm 207, Lally Building,
>>>  email:  magdon at cs.rpi.edu              CS Department, RPI,
>>>  tel:    518-276-4857                   110 8th Street,
>>>  fax:    518-276-4033                   Troy, NY 12180-3590.
>>>  web:    http://www.cs.rpi.edu/~magdon
>>>  key:    http://www.cs.rpi.edu/~magdon/MalikMagdon-Ismail.PublicKey.asc
>>> -------------------------------------------------------------------------- 
>>> 
>>> On Tue, 20 Jan 2009, Dave Przybylo wrote:
>>> 
>>>> A stock application is an application that we compiled ourselves. As in 
>>>> it is not modified by anyone outside the CS department because we release 
>>>> our code for others to view/modify.
>>>> 
>>>> Regards,
>>>> 
>>>> ----------------------------------------------------------------------------------------------- 
>>>> Dave Przybylo    <przybd at cs.rpi.edu>
>>>> Undergraduate Researcher
>>>> Worldwide Computing Laboratory ( http://wcl.cs.rpi.edu/ )
>>>> Department of Computer Science
>>>> Rensselaer Polytechnic Institute, 110 8th Street, Troy NY 12180, USA
>>>> 
>>>> ----------------------------------------------------------------------------------------------- 
>>>> 
>>>> On Jan 20, 2009, at 3:14 PM, Malik Magdon-Ismail wrote:
>>>> 
>>>>> Hi,
>>>>> 
>>>>> What is a stock application?
>>>>> 
>>>>> -Malik
>>>>> 
>>>>> 
>>>>> -------------------------------------------------------------------------- 
>>>>> Have Faith in Probability
>>>>> 
>>>>> Malik Magdon-Ismail
>>>>> Associate Professor of Computer Science
>>>>> Rensselaer Polytechnic Institute (RPI)
>>>>> 
>>>>> Office: Rm 312 Lally           mail:   Rm 207, Lally Building,
>>>>> email:  magdon at cs.rpi.edu              CS Department, RPI,
>>>>> tel:    518-276-4857                   110 8th Street,
>>>>> fax:    518-276-4033                   Troy, NY 12180-3590.
>>>>> web:    http://www.cs.rpi.edu/~magdon
>>>>> key:    http://www.cs.rpi.edu/~magdon/MalikMagdon-Ismail.PublicKey.asc
>>>>> 
>>>>> -------------------------------------------------------------------------- 
>>>>> 
>>>>> On Tue, 20 Jan 2009, Travis Desell wrote:
>>>>> 
>>>>>> I've been analyzing the data coming in from our stock applications and 
>>>>>> it looks like there's some kind of bug in the likelihood calculation. 
>>>>>> Here are plots of points along the direction generated by the hessian 
>>>>>> for stripes 79, 82 and 86:
>>>>>> 
>>>>>> files with _darwin are points only from os/x clients,  _linux is linux 
>>>>>> clients, and _stock is linux/windows/os x.  As you can see they're all 
>>>>>> having the same issue. It almost seems like two distinct lines are 
>>>>>> being made.
>>>>>> 
>>>>>> Does anyone have any idea what might be causing this?  Again, these are 
>>>>>> points only coming from our stock application, so it's not a matter of 
>>>>>> a bad application being out there.  I have a feeling this is what's 
>>>>>> throwing off the hessian calculation.
>>>>>> 
>>>>>> -- 
>>>>>> 
>>>>>> 
>>>>>> ---------------------------------------------------------------------------------------------------------- 
>>>>>> Travis Desell
>>>>>> <deselt @ cs.rpi.edu>
>>>>>> 1-518-878-7424
>>>>>> Worldwide Computing Laboratory ( http://wcl.cs.rpi.edu/ )
>>>>>> MilkyWay at Home ( http://milkyway.cs.rpi.edu/ )
>>>>>> Rensselaer Polytechnic Institute, 110 8th Street, Troy NY 12180, USA
>>>>>> 
>>>>>> 
>>>>>> ---------------------------------------------------------------------------------------------------------- 
>>>>> 
>>>> 
>>>> 
>>> 
>>> 
>> 
>
> -- 
> ----------------------------------------------------------------------------------------------------------
> Travis Desell
> <deselt @ cs.rpi.edu>
> 1-518-878-7424
> Worldwide Computing Laboratory ( http://wcl.cs.rpi.edu/ )
> MilkyWay at Home ( http://milkyway.cs.rpi.edu/ )
> Rensselaer Polytechnic Institute, 110 8th Street, Troy NY 12180, USA
> ---------------------------------------------------------------------------------------------------------- 
>
>