Information Processing in Living Systems

Gašper Tkačik, William Bialek · Annual Review of Condensed Matter Physics / arXiv · 2016 · biology · 10.1146/annurev-conmatphys-031214-014803 · record tkacik2016-information-living
tag layer · index · concepts · authors · עברית

Where this record's text came from. faceted 2026-08 by reading the locally held text (pdftext); every evidence string verified as an exact substring of that text before merging. Claim type is a forced fit: this is a review whose organising thesis is that life's mechanisms can be read as solutions to information-optimization problems, so 'mechanism' was chosen over 'existence'; the enum has no value for a synthesis. Claim relations is empty on purpose - the review reports and compares other people's results at length (Shannon, Barlow, Laughlin, Atick and Redlich, Smith and Lewicki, Kelly) but no verbatim sentence relates this article's own claim to a named prior work, and inferring one from a bare citation is what the rules forbid. The extracted text ends mid-sentence at 'These', so the closing discussion and reference list are missing; the arXiv line-noise header ('4 1 0 2 c e D 0 3 ...') is also part of the file. 2026-08-14, 2026-08-15 and 2026-08-17 schema-0.3 passes: every quote verified as an exact substring of the staged text and anchored at merge time; concept terms verified present; every edge endpoint an existing node.

This record’s own method is review, and the tags below follow from that. A review’s findings, quantities and statistics are things stated IN this paper, and some of them report results obtained elsewhere. No tag on this page names a different author. Measured across every review in this corpus, 81% of a review’s tags carry no citation at all — most of them are the review speaking. The corpus does not adjudicate the rest: read an unmarked tag as a claim this paper makes, not necessarily one it made first.

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Other fields define these differently the same word, defined another way in another discipline
noise 2 fields

Tags on this paper

Every tag the record carries, each linking to every other paper in the corpus that carries it. A tag appears here whether or not its words occur in the article — the spans below are only the ones a sentence in this paper licenses. Of the 8 concept tags on this paper, 5 are grounded in a quoted sentence.

information theory channel capacity mutual information biological information processing utility efficient representation efficient coding sequence logos THE PAPER'S QUESTION IS WHETHER AN INTUITION CAN BE FORMALISED, AND IT IS ASKED IN THOSE WORDS: in all these cases INTUITION TELLS US that information is FLOWING from the environment to a representation internal to the organism - CAN THIS INTUITION BE FORMALIZED? IF SO, CAN IT BE CONNECTED, QUANTITATIVELY, TO EXPERIMENTAL DATA? The scare quotes on `flowing` are the paper's, and they mark exactly what has to be earned THE ABSTRACT VOCABULARY IS SHOWN TO BE NEEDED ONLY WHERE A CONCRETE ONE IS MISSING: in a ferromagnet what carries information over long distances is the ORDER PARAMETER - and PRECISELY BECAUSE WE CAN IDENTIFY THE ORDER PARAMETER, WE DON'T NEED TO SPEAK ABSTRACTLY ABOUT INFORMATION. Rather than turning CARRY INFORMATION into a precise mathematical statement, one just computes correlation functions. The general term is a substitute for a specific one that is absent AND THE CONDITIONS UNDER WHICH THE ABSTRACT VOCABULARY BECOMES NECESSARY ARE SPELLED OUT: for most biological systems finding something like an order parameter REMAINS A DISTANT HOPE, SYMMETRIES ARE ABSENT, and EVEN LOCALITY IS NOT MUCH OF A GUIDE - UNDER THESE CONDITIONS, some MORE GENERAL APPROACHES to formalizing the intuition WOULD BE USEFUL. The need for the general term is derived from three specific things the field does not have A DISCIPLINARY TRADITION IS NAMED AS THE REASON FOR A TRADE-OFF, AND THE COST IS STATED IN THE SAME SENTENCE: Quotation withheld What is being traded, and on whose authority, are both on the page WHICH PARTS OF A TRANSFERRED FORMALISM ARE USEFUL DEPENDS ON THE DESTINATION FIELD, AND THE MISMATCH IS STATED: the ideas MOST WIDELY USED in thinking about biological systems are NOT NECESSARILY THOSE THAT HAVE BEEN MOST USEFUL in the enormously successful application of information theory to communication technology - SO OUR PERSPECTIVE HERE IS SOMEWHAT DIFFERENT from the standard text's THE MEASURE IS FORCED BY POSTULATES RATHER THAN CHOSEN, AND THE POSTULATES ARE LISTED FIRST: ANY ACCEPTABLE MEASURE OF INFORMATION MUST OBEY SOME CONSTRAINTS - it must grow with the number of equally likely answers; it must ADD across independent parts; and it must be the weighted sum along the paths of a tree of choices - and REMARKABLY, THESE POSTULATES ALLOW ONLY ONE POSSIBLE MEASURE OF INFORMATION, THE ENTROPY. A definition derived from desiderata, not stipulated TWO SEEMINGLY DIFFERENT QUESTIONS TURN OUT TO HAVE THE SAME ANSWER, WHICH IS WHAT LICENSES ONE WORD FOR BOTH: A SEEMINGLY VERY DIFFERENT QUESTION concerns the amount of SPACE required to write down the answer - and THE ANSWER IS AGAIN THE ENTROPY. One formal object serving as the answer to a question about knowledge and to a question about storage AN AMBIGUITY IN THE UNITS IS NAMED, RESOLVED BY CONVENTION, AND THE NAME IS ATTACHED TO THE CONVENTION: THERE IS SOME AMBIGUITY ABOUT UNITS - the alphabet is a choice and the constant is arbitrary - BUT if a binary alphabet is chosen and the constant set to one, ALL OF THE AMBIGUITY IS RESOLVED, and measured in these units they ARE CALLED BITS. The familiar name names a settled convention, not a quantity THE SAME QUANTITY IS GIVEN TWO DESCRIPTIONS OF OPPOSITE VALENCE AND ONE IS PREFERRED: Shannon's theorem MAKES PRECISE THE VAGUE STATEMENT made in many statistical mechanics classes, that entropy is related to our LACK of information about the microscopic state - and THE MORE POSITIVE VERSION IS THAT THE ENTROPY IS THE INFORMATION WE WOULD GAIN upon learning the full state. One object, a lack and a gain, and the author says which framing he prefers A PREDICTION IS RATED BY WHAT IT DID NOT NEED RATHER THAN BY HOW WELL IT FIT: the measured input/output relation agreed REMARKABLY with the theory, ESPECIALLY CONSIDERING THAT THERE ARE NO FREE PARAMETERS - and the result is credited with having INSPIRED THE COMMUNITY TO TAKE THESE IDEAS MORE SERIOUSLY. The absence of adjustable quantities is what the agreement is worth entropy biological systems information flow optimization noise communication channel transcription factor small-noise approximation transcription factor concentration linear correlation coefficient Bayesian correlation correlation coefficient mean average value review

Legend

relation to other work	`claim_relations`	how this paper stands to another: agrees, contradicts, extends, qualifies
claim type	`claim_type`	the shape of the claim: existence, mechanism, method, critique, prediction, null
concept edge	`concept_edges`	an asserted relation between two concepts, with the sentence asserting it
concept	`concepts`	an idea the paper works with, quoted where the paper uses it
content tag	`content_tags`	a finding, definition, quantity, statistic or variable named in the paper
limitation	`limitations`	what the paper says its evidence cannot support
mechanism	`mechanisms`	how the reported effect is said to come about
method	`method`	how the paper produced its evidence
phenomenon	`phenomenon`	the effect or regularity under study
sense	`senses`	a distinct use of a term, quoted where the paper fixes it
transfer	`transfers`	a method or concept carried in from another field
unrecordable relation	`unhoused_relations`	a relation the paper asserts that this vocabulary cannot express, with the reason

The paper

The full text is not reproduced here. This article is not cleared for redistribution, so the page carries the tag layer only. Its evidence sentences are withheld; the grounding status remains with each tag, and the article itself is at https://doi.org/10.1146/annurev-conmatphys-031214-014803. The reading view exists for the papers whose licence permits it.

Every tag on this page

claim_relations 1 · claim_type 1 · concept_edges 1 · concepts 5 · content_tags 16 · limitations 8 · mechanisms 10 · method 1 · phenomenon 1 · senses 3 · transfers 1 · unhoused_relations 2

Relations on this page carry a quotation for the claim. Where a relation was separately evidenced — and so tested against the vocabulary for its type — the row says so; none of 1 relation here carry that mark. The rest are the tagger’s reading of the sentence quoted beside them.

This record holds no controls. A layer is empty when the tagger recorded nothing in it — which is not the same as the paper having nothing to record.

facet	tag	field	conf.	whose words
claim_type	mechanism Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above.	`claim_type`		the paper's words
phenomenon	information flow in biological systems Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above.	`phenomenon`		the paper's words
method	review Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. also in: review	`method`		the paper's words
mechanisms	mechanisms Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. also in: THE PAPER'S QUESTION IS WHETHER AN INTUITION CAN BE FORMALISED, AND IT IS ASKED IN THOSE WORDS: in all these cases INTUITION TELLS US that information is FLOWING from the environment to a representation internal to the organism - CAN THIS INTUITION BE FORMALIZED? IF SO, CAN IT BE CONNECTED, QUANTITATIVELY, TO EXPERIMENTAL DATA? The scare quotes on `flowing` are the paper's, and they mark exactly what has to be earned	`mechanisms[0]`	0.95	the tagger's words
mechanisms	mechanisms Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. also in: THE ABSTRACT VOCABULARY IS SHOWN TO BE NEEDED ONLY WHERE A CONCRETE ONE IS MISSING: in a ferromagnet what carries information over long distances is the ORDER PARAMETER - and PRECISELY BECAUSE WE CAN IDENTIFY THE ORDER PARAMETER, WE DON'T NEED TO SPEAK ABSTRACTLY ABOUT INFORMATION. Rather than turning CARRY INFORMATION into a precise mathematical statement, one just computes correlation functions. The general term is a substitute for a specific one that is absent	`mechanisms[1]`	0.95	the tagger's words
mechanisms	mechanisms Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. also in: AND THE CONDITIONS UNDER WHICH THE ABSTRACT VOCABULARY BECOMES NECESSARY ARE SPELLED OUT: for most biological systems finding something like an order parameter REMAINS A DISTANT HOPE, SYMMETRIES ARE ABSENT, and EVEN LOCALITY IS NOT MUCH OF A GUIDE - UNDER THESE CONDITIONS, some MORE GENERAL APPROACHES to formalizing the intuition WOULD BE USEFUL. The need for the general term is derived from three specific things the field does not have	`mechanisms[2]`	0.95	the tagger's words
mechanisms	mechanisms Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. also in: A DISCIPLINARY TRADITION IS NAMED AS THE REASON FOR A TRADE-OFF, AND THE COST IS STATED IN THE SAME SENTENCE: Quotation withheld What is being traded, and on whose authority, are both on the page	`mechanisms[3]`	0.95	the tagger's words
mechanisms	mechanisms Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. also in: WHICH PARTS OF A TRANSFERRED FORMALISM ARE USEFUL DEPENDS ON THE DESTINATION FIELD, AND THE MISMATCH IS STATED: the ideas MOST WIDELY USED in thinking about biological systems are NOT NECESSARILY THOSE THAT HAVE BEEN MOST USEFUL in the enormously successful application of information theory to communication technology - SO OUR PERSPECTIVE HERE IS SOMEWHAT DIFFERENT from the standard text's	`mechanisms[4]`	0.95	the tagger's words
mechanisms	mechanisms Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. about this quote: EXTENDED: the first cut stopped four words short of "the entropy" - the answer the tag is about. Widening rather than weakening. The span ends on a comma because the next token is a footnote marker glued to a displayed formula ("answers,1 S[p] ="). also in: THE MEASURE IS FORCED BY POSTULATES RATHER THAN CHOSEN, AND THE POSTULATES ARE LISTED FIRST: ANY ACCEPTABLE MEASURE OF INFORMATION MUST OBEY SOME CONSTRAINTS - it must grow with the number of equally likely answers; it must ADD across independent parts; and it must be the weighted sum along the paths of a tree of choices - and REMARKABLY, THESE POSTULATES ALLOW ONLY ONE POSSIBLE MEASURE OF INFORMATION, THE ENTROPY. A definition derived from desiderata, not stipulated	`mechanisms[5]`	0.85	the tagger's words
mechanisms	mechanisms Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. also in: TWO SEEMINGLY DIFFERENT QUESTIONS TURN OUT TO HAVE THE SAME ANSWER, WHICH IS WHAT LICENSES ONE WORD FOR BOTH: A SEEMINGLY VERY DIFFERENT QUESTION concerns the amount of SPACE required to write down the answer - and THE ANSWER IS AGAIN THE ENTROPY. One formal object serving as the answer to a question about knowledge and to a question about storage	`mechanisms[6]`	0.95	the tagger's words
mechanisms	mechanisms Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. also in: AN AMBIGUITY IN THE UNITS IS NAMED, RESOLVED BY CONVENTION, AND THE NAME IS ATTACHED TO THE CONVENTION: THERE IS SOME AMBIGUITY ABOUT UNITS - the alphabet is a choice and the constant is arbitrary - BUT if a binary alphabet is chosen and the constant set to one, ALL OF THE AMBIGUITY IS RESOLVED, and measured in these units they ARE CALLED BITS. The familiar name names a settled convention, not a quantity	`mechanisms[7]`	0.95	the tagger's words
mechanisms	mechanisms Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. also in: THE SAME QUANTITY IS GIVEN TWO DESCRIPTIONS OF OPPOSITE VALENCE AND ONE IS PREFERRED: Shannon's theorem MAKES PRECISE THE VAGUE STATEMENT made in many statistical mechanics classes, that entropy is related to our LACK of information about the microscopic state - and THE MORE POSITIVE VERSION IS THAT THE ENTROPY IS THE INFORMATION WE WOULD GAIN upon learning the full state. One object, a lack and a gain, and the author says which framing he prefers	`mechanisms[8]`	0.95	the tagger's words
mechanisms	mechanisms Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. about this quote: EXTENDED BACKWARDS so the span carries the method as well as the verdict. NOTE ON HOW THIS NEARLY WENT WRONG: my first attempt at the start key was "By MEASURING natural scenes" and the paper says "By SAMPLING natural scenes". I typed the verb from memory instead of slicing it, the uniqueness assertion caught it, and the correct word came from the file. Slice, never type - including the words you are certain of. also in: A PREDICTION IS RATED BY WHAT IT DID NOT NEED RATHER THAN BY HOW WELL IT FIT: the measured input/output relation agreed REMARKABLY with the theory, ESPECIALLY CONSIDERING THAT THERE ARE NO FREE PARAMETERS - and the result is credited with having INSPIRED THE COMMUNITY TO TAKE THESE IDEAS MORE SERIOUSLY. The absence of adjustable quantities is what the agreement is worth	`mechanisms[9]`	0.85	the tagger's words
limitations	The review deliberately favours theoretical unity over biological detail. Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. what this limits: the level of biological detail in every claim: WE FOLLOW THE PHYSICS TRADITION OF EMPHASIZING THE UNITY OF THEORETICAL IDEAS AT THE EXPENSE OF SOME OF THE BIOLOGICAL COMPLEXITY	`limitations[0]`		the tagger's words
limitations	Entropy and mutual information are hard to estimate from finite samples, which limits the whole programme. Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. what this limits: every entropy or mutual-information estimate: THE DIFFICULTY OF ACTUALLY ESTIMATING THE ENTROPY OF A PROBABILITY DISTRIBUTION FROM A LIMITED SET OF SAMPLES	`limitations[1]`		the tagger's words
limitations	Information-theoretic quantities may not capture everything that matters biologically, since not all bits are equally useful to an organism. Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. what this limits: the sufficiency of the information-theoretic framing itself: ITS UNIVERSALITY IS ITS STRENGTH, BUT IT ALSO LEAVES ONE WITH AN UNCOMFORTABLE FEELING THAT THERE IS MORE TO THE STORY - not all bits are equal	`limitations[2]`		the tagger's words
limitations	The maximum-entropy approach to protein folding rests on data sufficiency and approximations that remain open questions. Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. what this limits: the maximum-entropy protein-folding results: THERE ARE MANY OPEN QUESTIONS ABOUT THE SUFFICIENCY OF THE AVAILABLE DATA AND THE APPROXIMATIONS	`limitations[3]`		the tagger's words
limitations	The connection between learning, statistical mechanics and field theory is explicitly out of scope. Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. what this limits: the scope of the review: the links to statistical mechanics and field theory ARE BEYOND THE SCOPE OF THIS REVIEW	`limitations[4]`		the tagger's words
limitations	The under-appreciation of the theory's limits is attributed to the title of the paper that founded it. Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. what this limits: the scope of information-theoretic claims about biology: the authors suggest it is not widely appreciated what the theory does and does not cover, perhaps because Shannon titled his work a mathematical theory of communication	`limitations[5]`	1.0	the tagger's words
limitations	The method is chosen precisely because it does not require knowing what matters. Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. what this limits: the use of information-theoretic measures here: they are adopted because one may be unsure which features are most relevant and may not know the biologically meaningful metric, and these measures are completely general	`limitations[6]`	1.0	the tagger's words
limitations	The strongest semantic claim in the review is made in a form that declines to assert it. Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. what this limits: the claim that information-theoretic clustering recovers meaning: the authors write that it is hard to resist saying so, which reports the temptation rather than making the claim	`limitations[7]`	1.0	the tagger's words
transfers	quantifying information processing in living systems using mutual information and entropy Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above.	`transfers[0]`		the tagger's words
concepts	mutual information Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. also in: mutual information	`concepts[2]`		the paper's words
concepts	utility Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. also in: utility	`concepts[4]`		the paper's words
concepts	efficient representation Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. also in: efficient representation	`concepts[5]`		the paper's words
concepts	efficient coding Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. also in: efficient coding	`concepts[6]`		the paper's words
concepts	sequence logos Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. also in: sequence logos	`concepts[7]`		the paper's words
unhoused_relations	adaptation → nonlinear transient response Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. NO BOUNDARY CAN BE DRAWN - the CONCEPTUAL form of the negative relation / This is a claim about the concepts themselves, not about this study's data. No edge type can express it: all eight assert that a relation HOLDS. The boundary fails because of a TIMESCALE - the response adjusts so fast that the two cannot be told apart - so the distinction is real in principle and unusable in practice.	`unhoused_relations[0]`		the tagger's words
unhoused_relations	Shannon’s theorem → the vague statement that entropy is related to our lack of information Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. THREE PAPERS, THREE DIFFERENT VERDICTS ON WHETHER A FORMALISM CAN BE SHOWN TO CAPTURE THE INFORMAL NOTION IT REPLACES - and no type in the vocabulary can express a disagreement about what KIND OF CLAIM something is. This paper reports that a theorem DID make a vague statement precise - the one made in many statistical mechanics classes - and then states the more positive version of it. turing1936-computable-numbers argues the identification rather than proving it; shor1997-factoring says making it a theorem would weaken it. 'same-as' and 'distinct-from' are both false here: the three are not making one claim or two, they are ruling differently on whether the identification is the sort of thing a proof can settle. All eight edge types assert that a relation holds between two concepts. Recorded per record, each row quoting only its own paper; the cross-paper half is this paraphrase, checkable by opening the other two., and the third case for an earlier note of ours - which by the rule that one is an observation and three make a proposal is the point at which the gap should be put to Shir.	`unhoused_relations[1]`	0.95	the tagger's words
senses	a bit - NOT A UNIT OF VALUE: the universality of information-theoretic quantities is called their strength, and in the same breath the authors note that bits may not be of equal value or utility to the organism, so a count of bits is silent about which of them the animal needed Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above.	`senses[0]`	1.0	the tagger's words
senses	information - AS A DELIBERATELY CONTENT-FREE MEASURE: chosen because the relevant features and the biologically meaningful metric may both be unknown, so generality is the reason for the choice rather than a side effect of it Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above.	`senses[1]`	1.0	the tagger's words
senses	meaning - CLAIMED ONLY BY NOT QUITE CLAIMING IT: an information-theoretic clustering produces semantic rather than merely syntactic coherence and the authors say it is hard to resist saying the approach extracts meaning, which leaves the assertion unmade while the reader makes it Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above.	`senses[2]`	1.0	the tagger's words
claim_relations	builds-on → Shannon information theory (1948) Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above.	`claim_relations[0]`		the tagger's words
concept_edges	mutual information —distinct-from→ utility Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. strength of the relation: 1 Audit 2026-09-28: DOUBTFUL - read against its full span and kept, but the span says not all bits MAY be of equal value or utility; hedged. also in: mutual information · utility	`concept_edges[0]`		the tagger's words
content_tags	1 — information a pianist's brain processes Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above.	`content_tags.quantities[0]`		the tagger's words
content_tags	1948 — when Shannon quantified information Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above.	`content_tags.quantities[1]`		the tagger's words
content_tags	1 — bacterial chemotaxis response time Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above.	`content_tags.quantities[2]`		the tagger's words
content_tags	life depends on information flow as much as on energy flow Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above.	`content_tags.findings[0]`		the tagger's words
content_tags	biological systems may have evolved to optimize information gathering Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above.	`content_tags.findings[1]`		the tagger's words
content_tags	mutual information is zero exactly when the variables are independent Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above.	`content_tags.findings[2]`		the tagger's words
content_tags	mutual information is the unique sensible measure of correlation Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above.	`content_tags.findings[3]`		the tagger's words
content_tags	transcription factor concentration Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. also in: transcription factor concentration	`content_tags.variables[1]`		the tagger's words
content_tags	linear correlation coefficient Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. also in: linear correlation coefficient	`content_tags.variables[2]`		the tagger's words
content_tags	mutual information Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. also in: mutual information	`content_tags.definitions[0]`		the tagger's words
content_tags	channel capacity Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. also in: channel capacity	`content_tags.definitions[1]`		the tagger's words
content_tags	entropy Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. also in: entropy	`content_tags.definitions[2]`		the tagger's words
content_tags	small-noise approximation Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. also in: small-noise approximation	`content_tags.definitions[3]`		the tagger's words
content_tags	Bayesian Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. about this quote: QUOTE REPAIRED: the extractor split a hyphen-space and the quote was recorded faithfully with the damage in it, which made it unanchorable. The repaired string is an EXACT SUBSTRING of the staged text - that is why it was accepted, not because a rule produced it. The text as originally recorded is kept in evidence as extracted. also in: Bayesian	`content_tags.statistics[0]`		the tagger's words
content_tags	correlation Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. about this quote: QUOTE RECOVERED FROM THE PAPER'S OWN CHARACTERS. The recorded quote was LETTERS-ONLY IDENTICAL to this stretch of the staged text but not an exact substring of it - spaces, hyphens, ligature glyphs or mathematical operators differed, so it could never anchor. This is the file's own text between the same two letters: not produced by a rule about the damage, copied out of the file. Round-trip checked (the recovered span is letters-only equal to the original) and length-checked. The text as originally recorded is kept in evidence as extracted. also in: correlation	`content_tags.statistics[1]`		the tagger's words
content_tags	mean Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. about this quote: QUOTE REPAIRED: the extractor split a ligature and the quote was recorded faithfully with the damage in it, which made it unanchorable. The repaired string is an EXACT SUBSTRING of the staged text - that is why it was accepted, not because a rule produced it. The text as originally recorded is kept in evidence as extracted. also in: mean	`content_tags.statistics[2]`		the tagger's words

Interpretive choices

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