Results 251 to 260 of about 83,949 (294)

Local likelihood density estimation in line transect sampling

Environmetrics, 2000
A novel semiparametric estimator for the probability density function of detected distances in line transect sampling is proposed. The estimator is obtained using a local likelihood density estimation approach, a technique recently proposed which affords the advantages of both parametric and nonparametric methods, i.e. accuracy and robustness. Moreover,
Lucio Barabesi
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A bias-corrected histogram estimator for line transect sampling

Communications in Statistics - Theory and Methods, 2018
ABSTRACTThe classical histogram method has already been applied in line transect sampling to estimate the parameter f(0), which in turns is used to estimate the population abundance D or the popula...
Omar Eidous, Fahid Al-Eibood
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On the Line Transect Sampling Method

Biometrics, 1974
Theory has been developed in the present paper for estimating wildlife density and its standard error by the line transect method of sampling using both right angle and radial distances and based on different assumptions than those made by Gates et al. [1968]. It is shown that relatively better fits are realized when the assumptions are tested with the
Sen, A. R., Tourigny, J., Smith, G. E. J.   +2 more
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Size Bias in Line Transect Sampling

Biometrics, 1987
Line transect sampling is used to estimate the number of individuals in a study area. It is usually assumed that the detections of individuals constitute independent events, and that the probability of detecting an item is a function of its perpendicular distance from the transect.
Drummer, Thomas D., McDonald, Lyman L.
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Some Mathematical Models for Line Transect Sampling

Biometrical Journal, 1985
AbstractANDERSON and POSPAHALA (1970) investigated the estimation of wildlife population size using the belt or line transect sampling method and devised a correction for bias, thus leading to an estimator with interesting characteristics. This work was given a uniform mathematical framework in BURNHAM and ANDERSON (1976).
Anderson, D. R., Burnham, K. P., Crain, B. R.   +2 more
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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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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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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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Adaptive kernel function using line transect sampling

AIP Conference Proceedings, 2018
The estimation of f(0) is crucial in the line transect method which is used for estimating population abundance in wildlife survey’s. The classical kernel estimator of f(0) has a high negative bias. Our study proposes an adaptation in the kernel function which is shown to be more efficient than the usual kernel estimator.
Baker Albadareen, Noriszura Ismail
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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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