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For the virtual forest tutorial, I used the area sampling technique. The random sampling strategy had by far the fastest estimated sampling time at 4hours 51minutes compared to the systematic strategy (12 hours 37 minutes) and the haphazard sampling times (13 hours 2 minutes).
For the two most common tree species, the eastern hemlock and sweet birch, the percentage error was low for the systematic strategy (7% and 5%) and was highest for the random strategy (19% and 36%) (Figure 1). The percent error from the haphazard strategy varied with the eastern hemlock having the lowest percent error at 6% and a high percent error of 21% for the sweet birch (Figure 1). Based on the percent errors for the most common species, the systematic strategy seems to be the most accurate, the random being the least accurate and the haphazard being unpredictable with one of the percent errors being low and the other being high.
When looking at the percent error for the two most rare species, the striped maple and the white pine, all the sampling strategies had large percent errors for at least one of the species; this shows that accuracy increases with species abundance and decreases with species rarity. The systematic strategy had large percent errors (178% and 100%) as well as the random strategy (185% and 48%) (Figure 1). The haphazard strategy had a comparatively lower percent error for the striped maple at 14% but the white pine had a large percent error at 138% (Figure 1). All the strategies for rare species were not able to accurately represent the population and the haphazard strategy having a high and low value again shows it is an unpredictable sampling strategy.
I think the systematic strategy was the most accurate when looking at the percent errors for all the tree species. Surprisingly the haphazard strategy had lower percent errors overall than the random strategy which had the largest overall percent errors.
