Bayesian evaluation of smartphone applications for forest inventories in small forest holdings

Ficko, Andrej (author)

There are increasingly advanced mobile applications for forest inventories on the market. Small enterprises and nonprofessionals may find it difficult to opt for a more sophisticated application without comparing it to an established standard. In a small private forest holding (19 ha, 4 stands, 61 standing points), we compared TRESTIMA, a computer vision-based mobile application for stand inventories, to MOTI, a smartphone-based relascope, in measuring the number of stems (N) and stand basal area (G). Using a Bayesian approach, we (1) weighted evidence for the hypothesis of no difference in N and G between TRESTIMA and MOTI relative to the hypothesis of difference, and (2) weighted evidence for the hypothesis of overestimating versus underestimating N and G when using TRESTIMA compared to MOTI. The results of the Bayesian tests were then compared to the results of frequentist tests after the p-values of paired sample t-tests were calibrated to make both approaches comparable. TRESTIMA consistently returned higher N and G, with a mean difference of +305.8 stems/ha and +5.8 m$^2$/ha. However, Bayes factors (BF$_{10}$) suggest there is only moderate evidence for the difference in N (BF$_{10}$ = 4.061) and anecdotal evidence for the difference in G (BF$_{10}$ = 1.372). The frequentist tests returned inconclusive results, with p-values ranging from 0.03 to 0.13. After calibration of the p-values, the frequentist tests suggested rather small odds for the differences between the applications. Conversely, the odds of overestimating versus underestimating N and G were extremely high for TRESTIMA compared to MOTI. In a small forest holding, Bayesian evaluation of differences in stand parameters can be more helpful than frequentist analysis, as Bayesian statistics do not rely on asymptotics and can answer more specific hypotheses.

• Language: English
• Keywords: forest inventory, mobile applications, Bitterlich relascope, private forest owners, Bayesian informative hypotheses, accuracy, forest management planning
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: BF - Biotechnical Faculty
• Publication status: Published
• Publication version: Version of Record
• Year: 2020
• Number of pages: 16 str.
• Numbering: Vol. 11, iss. 11, art. 1148
• PID: 20.500.12556/RUL-122443
• UDC: 630*6
• ISSN on article: 1999-4907
• DOI: 10.3390/f11111148
• COBISS.SI-ID: 38901763
• Publication date in RUL: 11.12.2020

Record is a part of a journal

• Title: Forests
• Shortened title: Forests
• Publisher: MDPI
• ISSN: 1999-4907
• COBISS.SI-ID: 3872166

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.
• Licensing start date: 01.11.2020

Secondary language

• Language: Slovenian
• Keywords: gozdna inventura, zasebni gozdovi, gozdnogospodarsko načrtovanje

Projects

• Funder: Other - Other funder or multiple funders
• Funding programme: Republic of Slovenia, Ministry of Agriculture, Forestry, and Food
• Project number: 2330-17-000077
• Acronym: FOREXCLIM

• Funder: ARRS - Slovenian Research Agency
• Project number: P4-0059
• Name: Gozd, gozdarstvo in obnovljivi gozdni viri