Impacts of sample ratio and size on the performance of random forest model to predict the potential distribution of snail habitats

Authors

• Yuanhua Liu, Fudan University
• Jun Zhang, Fudan University
• Michael P Ward, University of Sydney
• Wei Tu, Georgia Southern University
• Lili Yu, Georgia Southern UniversityFollow
• Jin Shi, Fudan University
• Yi Hu, Fudan University
• Fenghua Gao, Anhui Institute of Schistosomiasis Control
• Zhiguo Cao, Anhui Institute of Schistosomiasis Control
• Zhijie Zhang, Fudan University

Document Type

Article

Publication Date

7-3-2023

Publication Title

Geospatial health

DOI

10.4081/gh.2023.1151

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 (p0.05). 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.

Recommended Citation

Liu, Yuanhua, Jun Zhang, Michael P Ward, Wei Tu, Lili Yu, Jin Shi, Yi Hu, Fenghua Gao, Zhiguo Cao, Zhijie Zhang. 2023. "Impacts of sample ratio and size on the performance of random forest model to predict the potential distribution of snail habitats." Geospatial health, 18 (2). doi: 10.4081/gh.2023.1151
https://digitalcommons.georgiasouthern.edu/geo-facpubs/222

Copyright

This work is archived and distributed under the repository's Standard Copyright and Reuse License (opens in new tab). End users may copy, store, and distribute this work without restriction. For all other uses, permission must be obtained from the copyright owners or their authorized agents.