Thank you Sergey,

> 1) Are you trying to predict or detect anomalies?
I want to detect anomalies, not predict.

> 2) How are you encoding ECG data?
I use Adaptive Scalar Encoder.

Here is model params,
https://github.com/iizukak/ecg-htm/blob/master/model_params/model_params.py

And sample data (It’s big CSV File)
https://github.com/iizukak/ecg-htm/blob/master/data/normal.csv

> Also, make sure to resetSequenceStates every time you start feeding in data 
> from
> a new person.
OK, I keep in mind.

> Finally, you might want to shuffle the data
Shuffling the data is sound good.
I’ll try if person1, person2, person3, …
one after another of learning data dose not make enough good model.

I think I don’t have a trouble with extracting data,
but I'll read the paper you suggested.

Hope this answers your question.
Thanks a lot!


2015-10-22 18:18 GMT+09:00 Sergey Alexashenko <[email protected]>:
> Actually, I can write out the scenarios here.
>
> NuPIC should definitely be able to learn different people's heartbeats in
> one model. You have to give it plenty of data to learn on. Also, make sure
> to resetSequenceStates every time you start feeding in data from a new
> person. Finally, you might want to shuffle the data so that you don't feed
> it person 1, then person 2, then person 3, but rather a mixture of all the
> data to reduce bias towards the latest people (but I don't think that this
> is necessary to be honest).
>
> There is, however, the issue of encoding. I'm assuming that you are using a
> scalar encoder produced by swarming. That's fine, that's a quick approach
> and it might work (in fact I would bet that it will produce usable results -
> be mindful of swarming on a data set including different people's data,
> though!).
>
> However, if you think about the data type - ECG data, unlike, say, EEG data,
> consists of almost perfectly discrete steps (heartbeats) which could be
> matched to NuPIC timesteps very well. If you run through the trouble of
> extracting features from your data (there is ample literature on how to do
> it - see [1] for example), and creating encoders for all the
> intervals/amplitudes, I think that NuPIC would do a marvelous job. Note that
> this approach condenses the time interval per step to one per heartbeat and,
> thus, is not going to work if you are trying to do super-rapid detection or
> prediction (on a time scale shorter than one heartbeat). It is also more
> time-consuming for you - once again, swarming could work well enough.
>
> Hope this helps,
>
> Sergey
>
> [1] http://arxiv.org/pdf/1005.0957.pdf
>
>
>
> On Thu, Oct 22, 2015 at 1:58 AM, Sergey Alexashenko
> <[email protected]> wrote:
>>
>> Hello Kentaro,
>>
>> I think that NuPIC can definitely work with ECG data, but I need a little
>> more information about your project to make any helpful suggestions. Two
>> questions:
>>
>> 1) Are you trying to predict or detect anomalies? You use both terms, but
>> they involve somewhat different mechanisms.
>>
>> 2) How are you encoding ECG data?
>>
>> Best,
>>
>> Sergey
>>
>>
>> On Wed, Oct 21, 2015 at 10:07 PM, Kentaro Iizuka
>> <[email protected]> wrote:
>>>
>>> Hello NuPIC.
>>>
>>> Thank you Matt for post.
>>>
>>> Here is my question detail. (It is same as gitter post)
>>> https://gist.github.com/iizukak/72526863d3f504f2ff5e
>>>
>>> I hope somebody have good idea for that.
>>>
>>> Thank you!
>>>
>>>
>>> 2015-10-22 13:29 GMT+09:00 Matthew Taylor <[email protected]>:
>>> > Hello NuPIC,
>>> >
>>> > Check this out:
>>> > https://gitter.im/numenta/htm-challenge/archives/2015/10/21
>>> >
>>> > Watch the ECG anomaly in the video:
>>> > https://youtu.be/5KdwV-trMhE?t=1m41s
>>> >
>>> > He has an interesting question about how to train a model on a healthy
>>> > heartbeat, and it is expressed well with pictures in the link above. He
>>> > wants to train a model with the ECG history of more than one person to
>>> > get a
>>> > representation of a "healthy heartbeat". The problem is that every
>>> > person's
>>> > heartbeat is a little different. Is it feasible to train a model on
>>> > multiple
>>> > heartbeats in sequence? I'm not sure if it will work, but maybe someone
>>> > has
>>> > a better idea?
>>> >
>>> > Solving this problem would help in a lot of different signal analysis
>>> > applications of HTM...
>>> >
>>> > ---------
>>> > Matt Taylor
>>> > OS Community Flag-Bearer
>>> > Numenta
>>>
>>>
>>>
>>> --
>>> Kentaro Iizuka<[email protected]>
>>>
>>> Github
>>> https://github.com/iizukak/
>>>
>>> Facebook
>>> https://www.facebook.com/kentaroiizuka
>>>
>>
>



-- 
Kentaro Iizuka<[email protected]>

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