In:
Geospatial Health, PAGEPress Publications, Vol. 18, No. 2 ( 2023-07-03)
Abstract:
Few studies have considered the impacts of sample size and sample ratio of presence and absence points on the results of random forest (RF) testing. We applied this technique for the prediction of the spatial distribution of snail habitats based on a total of 15,000 sample points (5,000 presence samples and 10,000 control points). RF models were built using seven different sample ratios (1:1, 1:2, 1:3, 1:4, 2:1, 3:1, and 4:1) and the optimal ratio was identified via the Area Under the Curve (AUC) statistic. The impact of sample size was compared by RF models under the optimal ratio and the optimal sample size. When the sample size was small, the sampling ratios of 1:1, 1:2 and 1:3 were significantly better than the sample ratios of 4:1 and 3:1 at all four levels of sample sizes (p 〈 0.01) and there was no significant difference among the ratios of 1:1, 1:2 and 1:3 (p 〉 0.05). The sample ratio of 1:2 appeared to be optimal for a relatively large sample size with the lowest quartile deviation. In addition, increasing the sample size produced a higher AUC and a smaller slope and the most suitable sample size found in this study was 2400 (AUC=0.96). This study provides a feasible idea to select an appropriate sample size and sample ratio for ecological niche modelling (ENM) and also provides a scientific basis for the selection of samples to accurately identify and predict snail habitat distributions.
Type of Medium:
Online Resource
ISSN:
1970-7096
,
1827-1987
DOI:
10.4081/gh.2023.1151
Language:
Unknown
Publisher:
PAGEPress Publications
Publication Date:
2023
detail.hit.zdb_id:
2276179-2
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