The inference shifting concept is an historical source of confusion.
Please read:

- 
https://github.com/numenta/nupic/wiki/Online-Prediction-Framework#shifting-inferences
- 
http://lists.numenta.org/pipermail/nupic_lists.numenta.org/2015-September/011579.html
---------
Matt Taylor
OS Community Flag-Bearer
Numenta


On Mon, Nov 2, 2015 at 6:29 AM, Wakan Tanka <[email protected]> wrote:
> Hello Pascal,
>
> Yes of course I mean not predictable by NuPIC not anything else ;) I should
> say "Can this be generalized that if NuPIC returns bouncing (non stable)
> anomaly score TOO OFTEN...". There is always question what "TOO OFTEN" means
> but it is for broader discussion.
>
> No I do not use inference shifter, I was just predicting one step ahead and
> when I plot the graph it was obvious what is going on ... I thought
> inference shifter is useful with larger prediction steps.
>
> If I understand correct then without inference shifter prediction made in
> time T is for data in time T+1. Anomaly score in time T represent the
> "confidence of prediction accuracy" in time T if I can say it like that.
> Assume one step prediction for above.
>
> If I understand you correct then inference shifter allows you to use
> "another column" which puts prediction T+1 to T? I did not catch it well
> from your last message. Sorry
>
> Thank you.
>
>
>
>
>
> On 11/02/2015 12:52 PM, Pascal Weinberger wrote:
>>
>>
>> Not predictable using nupic, but as Matt said, give it it's time, or
>> better data until you interpret or judge anything :)
>>
>> But one quick question regarding you first point, if you use the inference
>> shifter (as it is done in most tutorials) then the results of the model are
>> already shifted to where they belong. So nupic outputs prediction and
>> anomaly to (in your case) t+1 but the inference shifter puts them there as
>> well... So do you use it?
>>
>>
>> Best,
>>
>> Pascal Weinberger
>>
>> ____________________________
>>
>> BE THE CHANGE YOU WANT TO SEE IN THE WORLD ...
>>
>>
>>> On 02 Nov 2015, at 10:57, Wakan Tanka <[email protected]> wrote:
>>>
>>>> On 11/02/2015 06:12 AM, Matthew Taylor wrote:
>>>>>
>>>>> On Sun, Nov 1, 2015 at 2:26 PM, Wakan Tanka <[email protected]> wrote:
>>>>>   1. If this is one step ahead prediction then the prediction value on
>>>>>      line n should correspond to the original value on line n+1
>>>>>      (assuming that NuPIC made good prediction and not mistake)?
>>>>
>>>>
>>>> If the prediction is perfectly right, yes.
>>>>
>>>>>   2. If first question is true can you please explain me the 179 line?
>>>>> On
>>>>>      line 179 there is prediction which equals 0 and on line 180
>>>>> original
>>>>>      value equals to 0 which is OK. But why I get anomaly score 1 on
>>>>> line
>>>>>      179?
>>>>
>>>>
>>>> Just because the best prediction is correct does not mean that the HTM
>>>> is confident that it is correct. For example, NuPIC might only be 23%
>>>> confident in the best prediction it gives, in which case the anomaly
>>>> score could be very high.
>>>>
>>>>>   3. Or you can look at it vice versa: Prediction on line 180 is equal
>>>>> to
>>>>>      0 but the original value on line 181 is 3. So I assume prediction
>>>>>      was wrong. Why anomaly score on line 180 equals to 0? Does it
>>>>> means
>>>>>      that NuPIC believe that it is predicting the correct value but in
>>>>>      fact it was wrong?
>>>>
>>>>
>>>> I would not pay too much attention to the anomaly score (or
>>>> predictions for that matter) until the model has seen a few thousand
>>>> rows of data. It looks like it has seen less than 200 rows as this
>>>> point, so the anomaly scores can vary wildly until it establishes what
>>>> the data patterns are.
>>>>
>>>> Regards,
>>>> ---------
>>>> Matt Taylor
>>>> OS Community Flag-Bearer
>>>> Numenta
>>>
>>>
>>> Hello Matt,
>>>
>>> Can this be generalized that if NuPIC returns bouncing (non stable)
>>> anomaly score then it is either because NuPIC does not see enough data or
>>> because the data are not predictable?
>>>
>>> Thank you very much
>>>
>>
>
>

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