An information theory framework for movement path segmentation and analysis
Data files
Aug 26, 2024 version files 242.87 MB
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list-DARsAsDataframes_owl.Rds
239.35 MB
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multi-DAR_sim.csv
3.52 MB
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README.md
2.39 KB
Abstract
Improved animal tracking technologies provide opportunities for novel segmentation of movement tracks/paths into behavioral activity modes (BAMs) critical to understanding the ecology of individuals and the functioning of ecosystems. Current BAM segmentation includes biological change point analyses and hidden Markov models. Here we use an elemental approach to segmenting tracks into µ‐step-long "base segments" and m-base-segment-long "words". These are respectively clustered into n statistical movement elements (StaMEs) and k "raw" canonical activity modes (CAMs). Once the words are coded using m extracted StaME symbols, those encoded by the same string of symbols, after a rectification processes has been implemented to minimize misassigned words, are identified with particular "rectified" CAM types. The percent of reassignment errors, along with information theory measures, are used to compare the efficiencies of coding both simulated and empirical barn owl data for a selection of parameter values and approaches to clustering.
README: Computational and dataset information
https://doi.org/10.5061/dryad.jm63xsjkv
Description of the data and file structure
Relocation data from an adult female barn owl (Tyto alba) is obtained using an ATLAS reverse GPS technology system at a relocation frequency of 0.25 Hz. It is available in the file list-DARsAsDataframes_owl.Rds. The simulation data (multi-DAR_sim.csv) has been generated using a two-mode movement simulator Numerus ANIMOVER_1 (Getz et al. (2023)).
Files and variables
File: list-DARsAsDataframes_owl.Rds
Description: This file corresponds to the adult female barn owl. Data is in the form of a list of dataframes, one for each diel activity routine (DAR; a 24 h period). The dataframes have several variables, the most relevant being the x and y position coordinates (in meters) and 'dateTime' (which represents time) in the 'POSIXct' format of R programming language.
File: multi-DAR_sim.csv
Description: This file has the two-mode relocation data simulated using Numerus ANIMOVER_1 (more details in Getz et al. (2023)).
Variables
- Day: Represents a "nominal day"; integer.
- Delta: Represents time, resets at the turn of each 'Day'; integer.
- X: Denotes x coordinate (initially X=0 with left-right continuity identification); numeric.
- Y: Denotes y coordinate (initially Y=0 with top-bottom continuity identification); numeric.
- Distance: Distance travelled (or speed) between previous and present relocation; numeric.
- Theta (Deg.): Heading angle in degrees; numeric.
- Resources: Quantifies how rich a resource patch is; numeric.
- Kernel: Represents movement modes; character.
Code/software
The codes can be found in Varun Sethi's GitHub repository Hierarchical-path-segmentation-II.
Access information
Other publicly accessible locations of the data:
- The barn owl individual GG41259 used for demonstrating the methods developed here is part of the population sample referenced here.
Data was derived from the following sources:
- Simulation data is generated from the software described in Getz et al. (2023)
Methods
The methods developed in this manuscript have been demonstrated on both empirical and simulated relocation data. The former corresponds to an adult female barn owl (Tyto alba) individual, which is part of a population tagged at our study site in the Harod Valley in northeast Israel. The simulated data has been generated using a two‐mode step‐selection kernel simulator called Numerus ANIMOVER_1 (Getz et al. (2023)).
Data processing has been carried out using a series of several machine learning and other algorithms presented in Varun Sethi's GitHub repository Hierarchical-path-segmentation-II.