SOP #23: Statistical Data Analysis. Version 1.01. Pacific Island Network Focal Terrestrial Plant Communities Monitoring Protocol. Unpublished National Park Service Report, Pacific Island Inventory and Monitoring Network, Hawaii National Park, Hawaii.
Ainsworth A. 2021. SOP #23: Statistical Data Analysis. Version 1.01. Pacific Island Network Focal Terrestrial Plant Communities Monitoring Protocol. Unpublished National Park Service Report, Pacific Island Inventory and Monitoring Network, Hawaii National Park, Hawaii.
This SOP describes how to analyze Pacific Island Network (PACN) Focal Terrestrial Plant Communities (FTPC) monitoring data for both status and trends. Status is described primary with summary statistics including means and variances, while trends are evaluated using Chi-square tests, McNemar’s test of symmetry, paired t-tests, repeated measures ANOVA, or generalized linear models, depending on the type of data and its distribution. Note that a Type I error level of 0.10 is assumed. Testing at this level may be conservative for long-term monitoring. Since a Type I error occurs when we erroneously find a trend that is not real, the consequences are to take management action to conserve the resource for which the trend was detected. The consequences of a Type II error may be more severe if native plant vigor or recruitment are decreasing without detection. The relative cost of each error make the use of a large Type I error rate reasonable for monitoring (Buhl-Mortensen 1996; Gibbs, et al. 1998; Mapstone 1995).