Plot design examples

Latest revision as of 13:04, 26 October 2013

These are some self-stuy test questions that might be relevant in context of planning a suitable plot design in national forest inventories or for the test in forest inventory:

• Explain why a major statistical planning criterium for the choice of a plot design is to capture as much of the given variability of the target variable as possible!

• List some target variables that could be estimated based on one dimensional lines as observation units!

• Explain the rational of a nested plot design, in which trees of different diameter classes are included in sub-plots of different area size (smaller trees in small plots, large trees in large plots)!

• What sources of information might be a suitable basis for the decision on plot design options if you carry out a NFI for the first time?

• Planning for field protocols and plot designs is very much a compromise between statistical considerations and feasability in practical field implementation. Explain why compact circular (sub-) plots are common, even if elongated rectagular plots might be more suitable from a pure statistical point of view!

• You are responsible to allocate a limited budget for the implementation of a national forest inventory. Would you rather opt for a small number of large plots or a large number of rel. small plots? Explain!

• A decision maker is arguing on your report: „you observed only 0.05 % of the forest area of our country in the field, i can‘t believe that these results are reliable!“ How can you defend your results? (describe how sampling intensity and sample size are affecting precision)