role of threshold!

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role of threshold!

Bhupesh Rawat
Dear Sir,
İ would like to know the impact of threshold in any system. How could it effect the results if not considered.

--
Thanks & Regards
Bhupesh Rawat.
Ph.D Scholar
Department of Computer Science,Babasaheb Bhimrao Ambedkar University
Vidya Vihar,Rai Bareilly road(Lucknow)
Ph. No: +91-9897065948

...........................................................................................................................
*A man is the best judge of himself and he has to pay the price for what he
does.*
...........................................................................................................................





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Re: role of threshold!

Eibe Frank-3
Are you referring to the implicit threshold used to decide on a classification based on the estimated class probabilities in a two-class classification problem?

Predicting the class with maximum class probability in a two-class problem corresponds to applying a threshold of 0.5: whichever class exceeds this threshold is the one that is predicted. In some applications, this is not the best approach. If not all types of misclassifications are equally costly, you can use CostSensitiveClassifier to adjust the implicit threshold by specifying an appropriate cost matrix. If you are using an evaluation metric for which the default 0.5 threshold is not necessarily optimal, such as F-measure, you can use the ThresholdSelector class to adjust the threshold so that your chosen evaluation metric is optimized.

Cheers,
Eibe

On Wed, Feb 28, 2018 at 2:23 PM, Bhupesh Rawat <[hidden email]> wrote:
Dear Sir,
İ would like to know the impact of threshold in any system. How could it effect the results if not considered.

--
Thanks & Regards
Bhupesh Rawat.
Ph.D Scholar
Department of Computer Science,Babasaheb Bhimrao Ambedkar University
Vidya Vihar,Rai Bareilly road(Lucknow)
Ph. No: <a href="tel:+91%2098970%2065948" value="+919897065948" target="_blank">+91-9897065948

...........................................................................................................................
*A man is the best judge of himself and he has to pay the price for what he
does.*
...........................................................................................................................





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Re: role of threshold!

Bhupesh Rawat
thanks for the answer.<div id="DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2"><br />
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On 2/28/18, Eibe Frank <[hidden email]> wrote:

> Are you referring to the implicit threshold used to decide on a
> classification based on the estimated class probabilities in a two-class
> classification problem?
>
> Predicting the class with maximum class probability in a two-class problem
> corresponds to applying a threshold of 0.5: whichever class exceeds this
> threshold is the one that is predicted. In some applications, this is not
> the best approach. If not all types of misclassifications are equally
> costly, you can use CostSensitiveClassifier to adjust the implicit
> threshold by specifying an appropriate cost matrix. If you are using an
> evaluation metric for which the default 0.5 threshold is not necessarily
> optimal, such as F-measure, you can use the ThresholdSelector class to
> adjust the threshold so that your chosen evaluation metric is optimized.
>
> Cheers,
> Eibe
>
> On Wed, Feb 28, 2018 at 2:23 PM, Bhupesh Rawat <[hidden email]> wrote:
>
>> Dear Sir,
>> İ would like to know the impact of threshold in any system. How could it
>> effect the results if not considered.
>>
>> --
>> Thanks & Regards
>> Bhupesh Rawat.
>> Ph.D Scholar
>> Department of Computer Science,Babasaheb Bhimrao Ambedkar University
>> Vidya Vihar,Rai Bareilly road(Lucknow)
>> Ph. No: +91-9897065948 <+91%2098970%2065948>
>>
>> ............................................................
>> ...............................................................
>> *A man is the best judge of himself and he has to pay the price for what
>> he
>> does.*
>> ............................................................
>> ...............................................................
>>
>>
>>
>>
>>
>> _______________________________________________
>> Wekalist mailing list
>> Send posts to: [hidden email]
>> List info and subscription status: https://list.waikato.ac.nz/
>> mailman/listinfo/wekalist
>> List etiquette: http://www.cs.waikato.ac.nz/~
>> ml/weka/mailinglist_etiquette.html
>>
>>
>


--
Thanks & Regards
Bhupesh Rawat.
Ph.D Scholar
Department of Computer Science,Babasaheb Bhimrao Ambedkar University
Vidya Vihar,Rai Bareilly road(Lucknow)
Ph. No: +91-9897065948

...........................................................................................................................
*A man is the best judge of himself and he has to pay the price for what he
does.*
...........................................................................................................................
_______________________________________________
Wekalist mailing list
Send posts to: [hidden email]
List info and subscription status: https://list.waikato.ac.nz/mailman/listinfo/wekalist
List etiquette: http://www.cs.waikato.ac.nz/~ml/weka/mailinglist_etiquette.html