How much does the average tree weigh in a forest To estimate

How much does the average tree weigh in a forest? To estimate the mean biomass of a tree in a forest, a researcher sampled 100 square plots (20 m by 20 m) by first marking a grid over a map for an entire forest and then randomly selecting grids using a random number generator. Within each plot, they assigned a number to each tree and then randomly selected 10 trees using a random number generator. Thus, in the study overall, there were 1000 trees sampled. The biomass of each tree was measured and the mean of these measurements was used to estimate the mean biomass of a tree in the forest. If ?T is the standard deviation for tree biomass in the population, and ?P is the standard deviation for the mean biomass of a tree among 20x20m plots, which of the following best represents the uncertainty in the mean biomass of a tree for the entire forest? Hint: decide whether plots or trees are the replicates. Question 8 options: SE=?T100? SE=?T1000? SE=?P100? SE=?P20

Solution

Standard error = s/vn

Answer: SE=?T1000