FIGURE 9.

Using points to estimate an area. The reference area (entire gray and blue areas of this figure) is probed with 25 randomly placed points to estimate the area of the blue circle within it. Twelve of the twenty‐five points fall onto the circle. The area of the circle can therefore be estimated to 12/25th of the reference area. In that we can arbitrarily choose the size of the reference area, we can calculate an estimate of the size of the circle [Color figure can be viewed at wileyonlinelibrary.com]