Sidebar 9.1
Definitions
Data and Information
Data exist as first-order information. This level represents unrelated
facts. Information is developed as data are related. The combination
of data and their relationships is information. Information flow up the
hierarchical chain to ecosystem managers must be focused into the
scope of things that the managers understand or the information will
be useless.
Communications theory
Claude Shannon of Bell Laboratories (1949) came up with a way of
measuring information that was based on the bandwidth needed to
transmit nonredundant data. Ecologists have adapted a form of this
measure (the Shannon–Weaver index) to measure diversity. This
index represents the most basic structure of data, namely the presence or absence of a given entity and the amount relative to the whole
of the entities measured. Information content is a representation of
data that has relationships to other data. This relationship can be in
time, space, or category.
Information content
The most basic information content of DNA expressed with the
Shannon-Weaver (SW) index is the representation of individual
nucleotides in DNA. This value is the sum of the logarithms of the
probability of four separate nucleotide bases (guanine, adenine, tyrosine, and cytosine, or GATC). The contextual informational content
of DNA is not just this simple index of the amount of GATC (firstorder information), but base-pair SW indices (second-order information) and triplicate SW indices (third-order information) give further
informational content to DNA. Because triplicates of nucleotides
code for amino acids, the triplicate–triplicate SW indices give information about protein coding. The informational content thus quickly
becomes a multiorder (interaction) phenomenon that can be difficult
to understand at much above the protein coding level. Higher-level
combinations of nucleotide sequences code for enzymes and other
complex biological compounds.
In the natural world, field measurements are often only first order
(quantity) because higher-order data measurements are usually difficult to make. Measuring all of the complex interactions in a swamp
or other natural system is out of the range of most biological studies.
By collecting pertinent and applicable data, models can be developed
that represent the complex nonlinear interactions that exist in the
natural world. Data collection must be able to support the level of
detail and interactions in the model.
Definitions
Data and Information
Data exist as first-order information. This level represents unrelated
facts. Information is developed as data are related. The combination
of data and their relationships is information. Information flow up the
hierarchical chain to ecosystem managers must be focused into the
scope of things that the managers understand or the information will
be useless.
Communications theory
Claude Shannon of Bell Laboratories (1949) came up with a way of
measuring information that was based on the bandwidth needed to
transmit nonredundant data. Ecologists have adapted a form of this
measure (the Shannon–Weaver index) to measure diversity. This
index represents the most basic structure of data, namely the presence or absence of a given entity and the amount relative to the whole
of the entities measured. Information content is a representation of
data that has relationships to other data. This relationship can be in
time, space, or category.
Information content
The most basic information content of DNA expressed with the
Shannon-Weaver (SW) index is the representation of individual
nucleotides in DNA. This value is the sum of the logarithms of the
probability of four separate nucleotide bases (guanine, adenine, tyrosine, and cytosine, or GATC). The contextual informational content
of DNA is not just this simple index of the amount of GATC (firstorder information), but base-pair SW indices (second-order information) and triplicate SW indices (third-order information) give further
informational content to DNA. Because triplicates of nucleotides
code for amino acids, the triplicate–triplicate SW indices give information about protein coding. The informational content thus quickly
becomes a multiorder (interaction) phenomenon that can be difficult
to understand at much above the protein coding level. Higher-level
combinations of nucleotide sequences code for enzymes and other
complex biological compounds.
In the natural world, field measurements are often only first order
(quantity) because higher-order data measurements are usually difficult to make. Measuring all of the complex interactions in a swamp
or other natural system is out of the range of most biological studies.
By collecting pertinent and applicable data, models can be developed
that represent the complex nonlinear interactions that exist in the
natural world. Data collection must be able to support the level of
detail and interactions in the model.