Paper · 1975 · Forest Science

Evaluating Accuracy of Tree Measurements made with Optical Instruments

David Bruce

3
claims
6
verbatim quotes
12
citations
2
research areas
✓
Open access · cc-by

Abstract

Abstract Several steps are needed to assay accuracy of optical instruments used to measure tree height and upper-stem diameter. Preliminary tests establish basic instrumental and observer accuracy under easy measuring conditions. In the forest, accuracy deteriorates because visibility is impaired. By use of controls and comparison with accurate linear measures, sources and size of most bias and blunders can be identified. Accuracy is limited by an interaction of instrument, observer, and conditions of measurement. Forest Sci. 21:421-426.

Abstract from the paper’s OpenAlex record; open copy licensed cc-by. Read at the source ↗

The text the model read, with the source record’s inline markup (italics, sub- and superscripts) rendered and its character entities decoded; quote offsets refer to the raw text.

Claims 3

Method / resourceobservedoriginal resultnegativemeasured

Claim · model-written summary

Optical instrument measurement accuracy deteriorated in forests when visibility was impaired.

Taxon
Treet0
Outcome
accuracye0
Direction
deterioratese0
Setting
foreste0

Not reportedComparatorValue

Verbatim

e0

“In the forest, accuracy deteriorates because visibility is impaired”

✓ located verbatim in the source · abstract, characters 230–297 · show in text ↑
t0

“Tree Measurements”

✓ located verbatim in the source · title, characters 23–40 · show in text ↑
Method / resourceobservedoriginal resultpositivemeasured

Claim · model-written summary

Controls and accurate linear measures identified sources and size of most measurement bias and blunders.

Taxon
Treet0
Outcome
sources and size of most bias and blunders can be identifiede0
Comparator
accurate linear measurese0

Not reportedValue

Verbatim

e0

“By use of controls and comparison with accurate linear measures, sources and size of most bias and blunders can be identified”

✓ located verbatim in the source · abstract, characters 299–424 · show in text ↑
t0

“Tree Measurements”

✓ located verbatim in the source · title, characters 23–40 · show in text ↑
Method / resourceobservedoriginal resultnegativemeasured

Claim · model-written summary

Instrument, observer and conditions of measurement jointly limited accuracy.

Taxon
Treet0
Outcome
Accuracy is limitede0
Qualifier
interaction of instrument, observer, and conditions of measuremente0

Not reportedComparatorValue

Verbatim

e0

“Accuracy is limited by an interaction of instrument, observer, and conditions of measurement”

✓ located verbatim in the source · abstract, characters 426–518 · show in text ↑
t0

“Tree Measurements”

✓ located verbatim in the source · title, characters 23–40 · show in text ↑