Hey all, Just a few quick questions about encoders I’d appreciate some feedback to.
1- Are there any specific properties that encoders need to have when designing one? What’s the rationale behind them if they exist? 2- The wiki refers to encoder outputs as SDRs. Is that necessarily the case and if so, to what properties of encoder design is that requirement attributed to? (i.e. why do I need an SDR to be the output of the encoder as opposed to a binary vector unconstrained in density?) 3- Is there a biological counterpart for encoders in the general sense? 4- Encoders perform quantization on the input stream by binning similar input patterns into hypercubes in feature space and assigning a single label (SDR or binary representation) to each bin. The encoder resolution determines the size of the hypercube. The SP essentially performs a very similar task by binning the outputs of the encoder in a binary feature space instead. City block distance determined by a threshold parameter controls the size of the hypercubes/bins. Why is this not viewed as a redundant operation by 2 consecutive modules of the HTM design? Is there a strong case for allowing for it? 5- Finally, is there any benefit to designing an encoding scheme that bins inputs into hyperspheres instead of hypercubes? Would the resulting combination of bins produce decision boundaries that might possibly allow for better binary classification performance for example? Thanks! Nick _______________________________________________ nupic mailing list [email protected] http://lists.numenta.org/mailman/listinfo/nupic_lists.numenta.org
