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Record W1480796957

A simple and effective forest stand mortality model

2009· article· en· W1480796957 on OpenAlexaff
Oscar Garcı́a

Bibliographic record

Venuenot available
Typearticle
Languageen
FieldEnvironmental Science
TopicForest ecology and management
Canadian institutionsUniversity of Northern British Columbia
Fundersnot available
KeywordsBasal areaThinningMathematicsStatisticsSet (abstract data type)ForestryApplied mathematicsGeographyComputer science
DOInot available

Abstract

fetched live from OpenAlex

Abstract. A whole-stand survival model is presented, that is parsimonious and well-behaved when extrapolated, making it particularly useful in data-poor situations. It is argued, on biological and systemtheoretical grounds, that a suitable differential equation for the mortality rate should contain number of trees and top height on the right-hand side, avoiding age, mean diameter, or basal area. Following Eichhorn’s hypothesis, site quality can be neglected by modelling rates relative to height growth. proposed model is dN/dH = −aN b H c,whereN is number of trees per unit area, H is top height, and a, b and c are parameters to be estimated. The equation can be integrated to predict mortality between any two points in time. Satisfactory performance is demonstrated with a white spruce data set from British Columbia. It is shown that the model generalizes concepts of relative spacing, and mortality models for radiata pine and Douglas-fir used by Beekhuis in New Zealand in the 1960’s. Asymptotic behaviour is related to the 3/2, Reineke, and relative spacing self-thinning laws. Limitations of the self-thinning theories and relationships among their various forms are discussed.

Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.

How this classification was reachedexpand

Full frame machine prediction

Teacher imitation

Not calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.

metaresearch head score (Codex)0.001
metaresearch head score (Gemma)0.001
Version: metacan-v3-hybrid-931329e0061cValidation status: machine_predicted_unvalidated
Candidate categoriesnone
Consensus categoriesnone
DomainCandidate signal: none · Consensus signal: none
Study designCandidate signal: Simulation or modeling · Consensus signal: Simulation or modeling
GenreCandidate signal: Empirical · Consensus signal: none
Teacher disagreement score0.007
Threshold uncertainty score0.024

Distilled classifier scores by category (both heads)

CategoryCodexGemma
Metaresearch0.0010.001
Meta-epidemiology (narrow)0.0010.000
Meta-epidemiology (broad)0.0010.001
Bibliometrics0.0010.001
Science and technology studies0.0000.000
Scholarly communication0.0010.001
Open science0.0030.001
Research integrity0.0010.001
Insufficient payload (model declined to judge)0.0070.001

Machine scores (provisional)

The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.

Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.

Opus teacher head0.007
GPT teacher head0.240
Teacher spread0.233 · how far apart the two teachers sit on this one work
Validation statusscore_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from it

Classification

machine, unvalidated

Machine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.

The models applied no category: nothing in the taxonomy fit this work.
Study designSimulation or modeling
Domainnot available
GenreEmpirical

How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".

Quick stats

Citations22
Published2009
Admission routes1
Has abstractyes

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