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University of Arizona (1972)

A statistical analysis of desert rock distributions

Heyman, Eugene Richard,

Titre : A statistical analysis of desert rock distributions

Auteur : Heyman, Eugene Richard,

Université de soutenance : University of Arizona

Grade : Master of Science (MS) 1972

A uniformity trial study, performed on two different six meter square sites, showed a half meter square quadrat to be the optimum size sampling’ unit in which desert rocks may be sampled. A nested sample was then taken from a typical Southern Arizona desert region. The data were taken as the observed frequencies of rocks in various size classes contained in each quadrat. The sample data and the uniformity trial data were fit to known theoretical distri butions. Rocks 45 mm and larger were found to fit conta gious distributions which showed that clumping existed among these rocks. The proportion of ground covered by rocks larger than 11.2 mm was estimated as 15.1$. The optimum sampling scheme appeared to be a stratified sample, since the ground coverage was divided into definite strata. Exact quantification of the strata was unable to be done, however. Therefore a simple random sample seemed to be the best approach as its variance was considerably lower than that of the nested sample.


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