Newly completed constituents are placed on an agenda, and items are successively taken off the agenda and used if possible as left corners of new, higher-level constituents, and to extend partially completed constituents.
Individually or in groups, successive hidden states model the more abstract, higher-level constituents to be extracted from observed noisy sequences, such as phonemes from phones, words from phonemes, or parts of speech from words.
There is typically a layer of input units (nodes), one or more layers of hidden units, and an output layer, where each layer has (excitatory and inhibitory) connections forward to the next layer, typically conveying evidence for higher-level constituents to that layer.
Models of explanatory reduction typically assume that reductive explanation is causal explanation, where a higher level feature is explained by the interaction of constituent parts.
Hence, the individual constituents of a system inform its higher level functions [ 1- 4].
This is a hierarchy in which entities at each level are constituents of entities at the next higher level.
Pixar emphasizes the team effort, having developed a "creative culture" -- a term Catmull uses repeatedly -- culminating in high-level all hands meetings at which movies or their constituent parts are torn apart, but in a respectful manner, and then rebuilt on a higher level.
Moreover, a cleanup step is frequently needed because of high level of other constituents accompanying the analyte.
Reproducible depletion of major protein constituents allows deeper penetration into the proteome, with low level constituents identified.
Follow another higher level.
Biological levels are often defined as levels of composition or organization, where higher levels are composed by lower-level constituents (Oppenheim and Putnam [1958]; Wimsatt [1994]).
