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In the virtual forest I chose to use Distance Based sampling.
Systematic sampling was the most efficient in terms of time spent sampling, but only by about 15 and 30 minutes respectively.
The actual densities varied widely with my estimated data from sampling. Haphazard sampling was the most accurate sampling strategy for common species, with an average error margin of 12.5%. The most accurate for rare species was Systematic sampling, with an average error margin of only 2.3%. My results showed that accuracy was better for more common species, which was not surprising. Although not recorded in the table below, I noticed that systematic sampling showed closer results for the species that were neither common nor rare. Because of wide ranges in error margins, it would be ideal to sample more than 24 points for a more accurate estimate.
Tree Species | Actual Density | Distance Systematic | % error | Distance Random | % error | Distance Haphazard | % error | |
Most Common | Eastern Hemlock | 469.9 | 516.5 | 9.9 | 368.2 | 21.6 | 399.3 | 15 |
2nd Most Common | Sweet Birch | 117.5 | 42.3 | 64 | 108.3 | 7.8 | 105.9 | 9.9 |
Least Common | White Pine | 8.4 | 8.5 | 1.2 | 21.7 | 158 | 0 | 100 |
2nd Least Common | Striped Maple | 17.5 | 16.9 | 3.4 | 32.5 | 85.7 | 8.1 | 53.7 |
Estimated Time | 4h15m | 4h29m | 4h44m |