Estimating density from surveys employing unequal-area belt transects
Fixed-width belt transects employed in surveys of irregular shaped regions will differ in length and, therefore, in area. When estimating density from such a sample, the unequal transect areas must be taken into account. A density estimator dividing the mean number of objects (e.g., plants or animals) per transect by the mean transect area is recommended. An alternative estimator, the mean density per transect, is applicable for equal-area transects but often has undesirable properties for unequal-area transects. The recommended density estimator is identified as a ratio estimator, and its standard error is derived from ratio estimation theory.
Key Wordsconsistent estimation quadrat sampling ratio estimator systematic sampling
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