Techniques for sampling employed in the virtual tutorial included random or systematic sampling. Systematic sampling along a topographic gradient had the quickest shown sampling time, that lasts 13 hours and 16minutes, whereas haphazard sampling took the longest, 16 hours and 12 minutes . For two common species- Eastern Hemlocks and sweet Birch , least species are yellow birch and red maple – the percentage errors of the different techniques are the following: The percentage error for the systematic or random sampling for Eastern Hemlock was 10.9%, while the haphazard sampling had a 13.5% error rate . The percent error for the Sweet Birch was 18.5% for haphazard sampling and 21.1% for systematic or random sampling. The percentage error for the Yellow Birch was 0.5% for haphazard sampling and 17.5% for systematic sampling. In the case of the red maple, the percentage error was 0% in case of haphazard sampling and 12.5% in case of systematic sampling.
Where there were few species, the accuracy dropped off tremendously. For example, in haphazard sampling,the red maple and yellow birch were both very low, but in systematic or random sampling, the yellow birch was high. In contrast to limited samples, when the presence or absence of a few samples might modify the sampling error, higher abundance of samples is likely to increase accuracy , necessitating a larger difference between estimated and actual.
In general, systematic sampling seemed to be more accurate than random sample.