Hi Subutai,

I'm adding a page to my blog (http://inbits.com) about this - it'll be live
shortly. Anyone please feel free to use this (or any other material - text
and images - on the blog) for the Wiki.

I'm using the blog instead of the Wiki, because I feel the latter should be
balanced and authoritative, whereas the blog is a good place to be
speculative and a little more opinionated about both the theory and NuPIC
itself.

Cheers,

Fergal Byrne


On Sun, Nov 24, 2013 at 1:31 AM, Subutai Ahmad <[email protected]> wrote:

>
> As Doug mentioned in another email, the quality of the discussion on this
> list has been very high. We are putting together a really nice collection
> of theoretical results on SDR’s. Marek, thanks for starting this thread. I
> would like to collect these in a more organized fashion. We have an initial
> page on the theory below:
>
> https://github.com/numenta/nupic/wiki/Sparse-Distributed-Representations
>
> Would someone like to take a crack at including some of the results and
> email discussions? The ideal format for me would be a summary list of the
> main points, plus hopefully a link to more detailed page for each result
> (maybe this could just link to the email).   We could include relevant
> results from Kanerva in the same format.
>
> Thanks,
>
> —Subutai
>
>
>
> On Fri, Nov 22, 2013 at 6:55 AM, Marek Otahal <[email protected]>wrote:
>
>> Guys,
>>
>> I want to run some benchmarks on the CLA, one of which includes what I
>> called (information) capacity.
>>
>> This is #number of patterns a spatial pooler (SP) (with a fixed number of
>> columns) (and probably fixed number of training rounds) can distinguish.
>>
>> So assuming I have a SP with 1000 columns and 2% sparsity (=20 cols ON at
>> all times) and an encoder big enough to express larege range of patterns
>> (say scalar encoder for 0...1.000.000.000).
>>
>> The top cap is (100 choose 20) which is some crazy number of 5*10^20. All
>> these SDRs will be sparse, but not distributed (right??) because a change
>> in one bit will already be another pattern.
>>
>> So my question is, what is the "usable" capacity where all outputs are
>> still sparse (they all are) and distributed (=robust to noice). Is there a
>> percentage of bits (say 20% bits chaotic and still recognizes the pattern
>> still considered distributed/robust?)
>>
>>
>> Or is it the other way around and the SP tries to maximize this robustnes
>> for the given number of patterns it is presented? I if I feed it huge
>> number of patterns I'll pay the obvious price of reducing the border
>> between two patterns?
>>
>> Either way, is there a reasonable way to measure what I defined a
>> capacity?
>>
>> I was thinking like:
>>
>> for 10 repetitions:
>>    for p in patterns_to_present:
>>       sp.input(p)
>>
>> sp.disableLearning()
>> for p in patterns_to_present:
>>    p_mod = randomize_some_percentage_of_pattern(p, percentage)  # what
>> should the percentage be? see above
>>    if( sp.input(p) == sp.input(p_mod):
>>         # ok, it's same, pattern learned
>>
>>
>> Thanks for your replies,
>> Mark
>>
>>
>> --
>> Marek Otahal :o)
>>
>> _______________________________________________
>> nupic mailing list
>> [email protected]
>> http://lists.numenta.org/mailman/listinfo/nupic_lists.numenta.org
>>
>>
>
> _______________________________________________
> nupic mailing list
> [email protected]
> http://lists.numenta.org/mailman/listinfo/nupic_lists.numenta.org
>
>


-- 

Fergal Byrne, Brenter IT

<http://www.examsupport.ie>http://inbits.com - Better Living through
Thoughtful Technology

e:[email protected] t:+353 83 4214179
Formerly of Adnet [email protected] http://www.adnet.ie
_______________________________________________
nupic mailing list
[email protected]
http://lists.numenta.org/mailman/listinfo/nupic_lists.numenta.org

Reply via email to