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Below are the results of the 3 sampling strategies used in the virtual forest tutorial:
| Virtual Forest Assignment Table | Sampling Method | ||
| Species | Systematic | Random | Haphazard |
| Eastern Hemlock
True: 469.9 |
Estimated: 408.0
Percentage Error: 13.2% |
Estimated: 508.7
Percentage Error: 8.3% |
Estimated: 388.0
Percentage Error: 17.4% |
| Sweet Birch
True: 117.5 |
Estimated: 92.0
Percentage error: 21.7% |
Estimated: 130.4
Percentage Error: 11.0% |
Estimated: 160.0
Percentage Error: 36.2% |
| Yellow Birch
True: 108.9 |
Estimated: 96.0
Percentage Error: 11.8% |
Estimated: 78.3
Percentage Error: 28.1% |
Estimated: 156.0
Percentage Error: 43.3% |
| Chestnut Oak
True: 87.5 |
Estimated: 124.0
Percentage Error: 41.7% |
Estimated: 108.7
Percentage Error: 24.2% |
Estimated: 100.0
Percentage Error: 14.3% |
| Red Maple
True: 118.9 |
Estimated: 140.0
Percentage error: 17.7% |
Estimated: 126.1
Percentage Error: 6.1% |
Estimated: 108.0
Percentage Error: 9.2% |
| Striped Maple
True: 17.5 |
Estimated: 36.0
Percentage error: 105.7% |
Estimated: 13.0
Percentage Error: 25.7% |
Estimated: 28.0
Percentage Error: 60% |
| White Pine
True: 8.4 |
Estimated: 0.0
Percentage error: 100% |
Estimated: 0.0
Percentage Error: 100% |
Estimated: 8.0
Percentage Error: 4.8% |
- Based on the information provided, the fastest estimated sampling time was the random sampling method estimated at 12 hours and 19 minutes.
- The 2 most common species are the Eastern Hemlock and Sweet Birch. As you can see from the data presented above, the random sampling method yielded the lowest percentage error. For the 2 rarest species – Striped maple and White pine – the random sampling method yielded the lowest percentage error for only 1 of them (Striped maple), whereas the White pine’s lowest percentage error was in the hap hazardous sampling method. The accuracy did seem to change with species abundance generally speaking.
- After taking the mean percentage error of each sampling strategy these were my results – Systematic (44.5%), Random (29.1%) and Hap Hazardous (26.5%). This would be indicative that the Hap Hazardous Sampling Strategy is the most accurate out of all 3 strategies.
Your table did not show up properly on the blog, you should be able to preview and update if something doesn’t work quite right.
Was there much different in time between fastest and slowest sampling?
Hi Robyn, sorry for the delay in replying to this comment! I think the table has been fixed so that you are able to see it, correct?