Ben, On 7/22/08, Benjamin Johnston <[EMAIL PROTECTED]> wrote:
> > /Restating (not copying) my original posting, the challenge of effective >> unstructured learning is to utilize every clue and NOT just go with static >> clusters, etc. This includes temporal as well as positional clues, >> information content, etc. PCA does some but certainly not all of this, but >> considering that we were talking about clustering here just a couple of >> weeks ago, ratcheting up to PCA seems to be at least a step out of the >> basement./ >> > > You should actually try PCA on real data before getting too excited about > it. Why, as I have already conceded that virgin PCA isn't a solution? I would expect it to fail in expected ways until it is repaired/recreated to address known shortcomings, e.g. that it works on linear luminosity rather than logarithmic luminosity. In short, I am not ready for data yet - until I am first tentatively happy with the math. > Clustering and dimension reduction are related, but they are different and > equally valid techniques designed for different purposes. Perhaps you missed the discussion a couple of weeks ago, where I listed some of the UNstated assumptions in clustering that are typically NOT met in the real world, e.g.: 1. It presumes that cluster exist, whether or not they actually do. 2. It is unable to deal with data that has wildly different importance. 3. Corollary to 2 above, any random input completely trashes it. 4. It is designed for neurons/quantities where intermediate values have special significance, rather than for fuzzy indicators that are just midway between TRUE and FALSE. This might be interesting for stock market analysis, but has no (that I know of) parallel in our own neurons. > It is absurd to say that one is "ratcheting up" from the other. I agree that they do VERY different jobs, but I assert that the one that clustering does has nothing to do with NN, AGI, or most of the rest of the real world. I short, I am listening and carefully considering all arguments here, but in this case, I am still standing behind my "ratcheting up" statement, at least until I hear a better challenge to it. Steve Richfield ------------------------------------------- agi Archives: https://www.listbox.com/member/archive/303/=now RSS Feed: https://www.listbox.com/member/archive/rss/303/ Modify Your Subscription: https://www.listbox.com/member/?member_id=8660244&id_secret=108809214-a0d121 Powered by Listbox: http://www.listbox.com
