Unbiased Systematic Sampling Plans for the Line Intercept Method Vegetation, Forest Floor

Abstract

Experimentors have been using cost-efficient systematically located transects in the line intercept method for some time with little support from mathematical statistics. In this paper, it is shown that for rectangular regions the usual line intercept estimators for cover, density, and other attributes are unbiased for certain systematic sampling plans. The estimators are approximately unbiased for "large" irregularly shaped study regions.