Jennifer A Miller, PhD

Entries Tagged as 'publication'

Book chapter on Tapir movement

January 28th, 2019 · No Comments

Jennifer and 2 of her former and current doctoral students (Cody Schank and Brendan Hoover, respectively) published a chapter on the impact of Hurricane Otto on Baird’s Tapir movement in Nicaragua in Movement Ecology of Neotropical Forest Mammals

Tags: GIS · grad students · movement pattern analysis · publication

New paper on Science of Movement in IJGIS

January 25th, 2019 · No Comments

Jennifer was a co-author on a new foresight paper with Harvey Miller, Somayeh Dodge, and Gil Bohrer: ‘Towards an integrated science of movement: converging research on animal movement ecology and human mobility science.” This paper was a result of two NSF-funded workshops on movement analysis in Nov. 2016 (UT-Austin) and May 2017 (OSU).

Tags: GIS · movement pattern analysis · publication

PhD student Cody Schank lead author in Diversity & Distributions paper

September 30th, 2017 · No Comments

Cody Schank (PhD expected 2018) is the lead author of a collaborative paper that compares different statistical methods to model the potential distribution of Baird’s Tapir. The abstract is below and the article can be found here:

Aim

We test a new species distribution modelling (SDM) framework, while comparing results to more common distribution modelling techniques. This framework allows for the combination of presence-only (PO) and presence-absence (PA) data and accounts for imperfect detection and spatial bias in presence data. The new framework tested here is based on a Poisson point process model, which allows for predictions of population size. We compared these estimates to those provided by experts on the species.

Species and Location

Presence data on Baird’s tapir (Tapirus bairdii) throughout its range from southern México to northern Colombia were used in this research, primarily from the years 2000 to 2016.

Methods

Four SDM frameworks are compared as follows: (1) Maxent, (2) a presence-only (PO) SDM based on a Poisson point process model (PPM), (3) a presence-absence (PA) SDM also based on a PPM and (4) an Integrated framework which combines the previous two models. Model averaging was used to produce a single set of coefficient estimates and predictive maps for each model framework. A hotspot analysis (Gi*) was used to identify habitat cores from the predicted intensity of the Integrated model framework.

Results

Important variables to model the distribution of Baird’s tapir included land cover, human pressure and topography. Accounting for spatial bias in the presence data affected which variables were important in the model. Maxent and the Integrated model produced predictive maps with similar patterns and were considered to be more in agreement with expert knowledge compared to the PO and PA models.

Main conclusions

Total abundance as predicted by the model was higher than expert opinion on the species, but local density estimates from our model were similar to available independent assessments. We suggest that these results warrant further validation and testing through collection of independent test data, development of more precise predictor layers and improvements to the model framework.

 

Tags: grad students · publication

New article on analyzing dynamic interactions

June 19th, 2015 · No Comments

A new paper that continues my research on analyzing dynamic interactions using GPS data has just been published. This article employs a null model approach to assess how six currently used dynamic interaction metrics vary in terms of the type and magnitude of interaction they measure. ‘Towards a better understanding of dynamic interaction metrics for wildlife: a null model approach‘ (also see ‘Using spatially explicit simulated data to analyze animal interactions: a case study with brown hyenas in northern Botswana‘). This work will be presented as part of a special Frontiers in GIScience Research session at the ESRI User Conference July 22, 2015.

This research is supported by NSF #1424920.

Tags: conference · GIS · movement pattern analysis · publication

Progress Report editorship at PiPG

August 4th, 2014 · No Comments

I was recently invited to serve as the Progress Report editor for Progress in Physical Geography.  This will entail commissioning short (5000 words max) papers that cover new developments in an area related to some aspect of geomorphology, climatology, biogeography & landscape ecology, or human-environment interaction.

 

Tags: publication

PiPG Progress Report

February 24th, 2014 · No Comments

Another SDM-related progress report in Progress in Physical Geography is coming out. This one is on the use of simulated data to assess models.

Tags: GIS · publication · simulated data · spatial analysis · species distribution models

Progress report in PiPG

January 3rd, 2014 · No Comments

The first in a series of progress reports on species distribution models I’ve been invited to contribute to Progress in Physical Geography was published in 2012. This report focused on spatial autocorrelation and nonstationarity (doi: 10.1177/0309133312442522), the second one is on using simulated data (estimated publication in early 2014).

Tags: autocorrelation · GIS · publication · spatial scale · species distribution models

Analyzing interactions between brown hyenas in N. Botswana

January 3rd, 2014 · No Comments

image350This project originated as an exploratory study to see how GIScience concepts and methods can be used to analyze and understand movement of and interactions between brown hyenas in Northern Botswana. Correlated random walks were used as a ’null model’ to study movement patterns and interaction rates and several different dynamic interaction metrics were compared. This work was recently published in Transactions in GIS and was supported by a UT Vice President of Research Grant.

 

Tags: GIS · movement pattern analysis · publication · simulated data