Results 151 to 160 of about 6,368,094 (187)

Kernel Methods in Line and Point Transect Sampling

Biometrics, 1998
Summary: We consider kernel estimation of population density based on size and distance data in line and point transect sampling. Asymptotic normality of the estimators is established in each setting, with very weak assumptions imposed on the random sample size.
Mack, Y. P., Quang, Pham X.
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Spatial models for line transect sampling

Journal of Agricultural, Biological, and Environmental Statistics, 2004
This article develops methods for fitting spatial models to line transect data. These allow animal density to be related to topographical, environmental, habitat, and other spatial variables, helping wildlife managers to identify the factors that affect abundance.
Sharon L. Hedley, Stephen T. Buckland
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Bayesian Estimation of Animal Abundance for Line Transect Sampling

Biometrics, 1995
Summary: This paper develops a Bayesian model for estimating the density of a closed animal population from data obtained by the line transect method. The detection function is assumed to be half-normal and the data are neither grouped nor truncated. A Bayes estimator is constructed with respect to a gamma prior density and two loss functions: relative
Karunamuni, Rohana J., Quinn, Terrance J. II.   +1 more
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Perpendicular Distance Models for Line Transect Sampling

Biometrics, 1985
Perpendicular distance line transect models are examined to assess whether any single model can provide a general procedure for analysing line transect data. Of the two-parameter models considered, the hazard-rate model appears promising, whereas the exponential power series and exponential quadratic models do not.
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Efficiency and Bias in Strip and Line Transect Sampling

The Journal of Wildlife Management, 1985
Efficiency and relative bias of strip transect and line transect (Fourier series estimator) survey methods were compared. Comparisons involved the negative exponential and half-normal detection functions for expected sample sizes of 40, 60, and 100 and three levels of spatial aggregation. Efficiency and bias were computed as functions of strip transect
Kenneth P. Burnham, David R. Anderson, Jeffrey L. Laake   +2 more
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Zigzag survey designs in line transect sampling

Journal of Agricultural, Biological, and Environmental Statistics, 2004
Zigzag survey lines are frequently used in shipboard and aerial line transect surveys of animal populations. Analysis proceeds assuming that coverage probability through the survey region is uniform. We show that the two types of zigzag design that are in wide use do not generally have this property, and explore the degree of bias in abundance ...
Samantha Strindberg, Stephen T. Buckland
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Line Transect Sampling with Unknown Probability of Detection along the Transect

Biometrics, 1989
SUMMARY A model is given for line transect sampling for the purpose of estimating animal population density which makes no assumption about the value of the detection probability along the transect or about the form of the detection probability function other than continuity.
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Adjusting for Group Size Influence in Line Transect Sampling

The Journal of Wildlife Management, 1990
In some line transect surveys, the population of interest consists of groups or clusters of individuals rather than single items. If group size influences the probability of detecting a group, then the observed group size data are size-biased. This can lead to overestimation of the true mean group size and hence could lead to overestimation of the ...
Thomas D. Drummer, Anthony R. Degange, Larry L. Pank, Lyman L. McDonald   +3 more
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Line-transects : Sampling application to a French Guianan rainforest Running head : line-transects sampling in French Guiana

mamm, 2000
La gestion des ressources naturelles est une preoccupation recente en Guyane. Les sites d'etude se multiplient dorenavant sur le territoire. L'evaluation des impacts de la chasse et de l'exploitation forestiere sur les populations de grands mammiferes et oiseaux constitue un axe de recherche privilegie. Les methodes d'inventaire par transects lineaires
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Confidence Intervals for Densities in Line Transect Sampling

Biometrics, 1990
We consider the problem of estimating the density D of a population of objects or animals with ungrouped data from line transect sampling. We present a method of deriving an approximate confidence interval for D. This confidence interval requires the estimation of a certain standard deviation by the bootstrap method.
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