Continuing the discussion from The art of SDRs:
Some of you might be thinking…
Hey, you call this stuff HTM but there’s no Hierarchy? What gives?
The software architecture for hierarchies exists within both HTM.Java and NuPIC (and Comportex, right @floybix?). You can create models and link them together into a hierarchy, with lower levels passing data up into higher levels.
The algorithmic mechanism for creating an effective learned spatiotemporal hierarchy using one layer of an HTM is still very much a research topic. A good mechanism for temporal pooling within a hierarchical architecture is an active area of research, stay tuned for upcoming details.
Again, some of you might be thinking…
That’s false advertising to call your system HTM if there is no hierarchy implemented!
Numenta has created an effective hierarchy in the past (remember we’ve been working on this for over 10 years now). You can get some details about our old implementations of HTM (previously called “CLA” for Cortical Learning Algorithm) from @Subutai in this video from last year’s HTM Challenge:
We actually built a vision system with the first generation of algorithms that included hierarchy. Read more in this old mailing list post.
I just wanted to reassure those of you who might be new to this community that we know hierarchy works, and we know it is necessary to enable a lot more features of intelligence. We’ve spent most of our research time over the past several years ensuring that one node in the hierarchy is properly biologically-constrained.