Post 4 – Sampling Strategies

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For the sample strategies, I used area based sampling techniques.  The sampling time was actually very close to the same for all three strategies, with systematic being the fastest at 12 hours, 37 minutes, random being second at 12 hours, 39 minutes, and finally haphazard at 13 hours, 1 minute.  The percentage error for the two most common species found systematic and random to be the most accurate.  But looking just at eastern hemlock, the most common species, Random was the most accurate, then systematic, and finally haphazard.  The percentage errors found in the two rare species varied more so, with systematic actually being the least accurate overall.  However, looking at just the most rare species, white pine, Random was the least accurate, as there were no white pine found in those sample plots, systematic was next, and haphazard was the most accurate.  The accuracy generally decreased as species abundance decreased, which is logical, as some sampling strategies found none of the rare trees, making their percentage of error 100%, which is more likely to happen the less frequent a species is.  When the species abundance is higher, systematic and random sampling appear to be more accurate, while haphazard just happened to more accurate in rare species.  The transect lines being used (systematic) for rare species is the least accurate as the area is large, and following a single bearing is unlikely to capture all that the area encompasses.  However, if the area was stratified before sampling, a transect line would be as accurate.  So, all the sampling strategies are likely close to the same accuracy, and if done properly, all strategies likely have very similar accuracy.

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