Abstract Detail



Floristics & Taxonomy

Williams , Justin Kirk [1].

Piecewise Regression Analysis of Herbarium Specimens: Finding a Breakpoint for the Botanist Effect.

Geo-referenced herbarium specimens from Herbarium across the globe were accessed and mapped in GIS. Using 10 km increments, the number of herbarium specimens at increasing distances from the corresponding herbarium was calculated. Results from linear regression analysis show a negative correlation between herbarium specimens and distance from herbarium. The data were then analyzed using piecewise regression analysis to determine a breakpoint/threshold distance where the number of herbarium collections significantly drops. The various herbaria analyzed have separate breakpoints that range between 110-180 kilometers. The results presented here provide evidence supporting an earlier observation, coined the “Botanist Effect,” which hypothesized that botanists concentrate their collecting effort in areas closer to the herbarium where they work.


1 - Sam Houston State University, Biological Sciences, Huntsville, TX, 77320-2116, USA

Keywords:
ascertainment bias
botanist effect.

Presentation Type: Oral Paper
Number:
Abstract ID:1021
Candidate for Awards:None


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