Difference between revisions of "Glossary"

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'''hRef''' is the reference smoothing parameter in kernel analyses ( SD / sixth root N )
 
'''hRef''' is the reference smoothing parameter in kernel analyses ( SD / sixth root N )
  
'''Hull''' is a polygon with vertices fitted to a set of locations
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'''Hull''' is a polygon with vertices fitted to a set of locations; a Convex Hull has all external angles greater than 180°.
  
 
'''Incremental analysis''' estimates and plots the change in range area as successive locations are added.
 
'''Incremental analysis''' estimates and plots the change in range area as successive locations are added.
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'''Location Qualifying Variables''' (LQVs) are time, activity, habitat, values associated with x,y coordinates.
 
'''Location Qualifying Variables''' (LQVs) are time, activity, habitat, values associated with x,y coordinates.
  
'''Nearest neighbour distances''' are the minimum distance between spatially separate locations.
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'''Nearest Neighbour distances''' are the minimum distance between spatially separate locations.
  
'''Neighbour Linkage Analyses''' estimate Hulls round locations whose individual or summed Nearest neighbour distances do not exceed a certain value.  
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'''Neighbour Linkage analyses''' estimate Hulls round locations whose individual or summed Nearest neighbour distances do not exceed a certain value.  
  
'''Objective Cores''' TODO
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'''Objective Cores''' exclude Locations more isolated than a criterion distance based on the distribution of all Nearest Neighbour distances.
  
'''OREP''' Objective Restrictive Edge Polygons TODO
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'''OREP''' Objective Restrictive Edge Polygons have maximum peripheral edge distances less than a criterion based on the distribution of all Nearest Neighbour distances.
  
'''Outlier locations''' are those beyond the main distribution of locations.
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'''Outlier locations''' are those more isolated than a criterion distance based on the distribution of all Nearest Neighbour distances.
  
 
'''Overlap matrices''' are formed as % overlaps of range A on B and B on A.
 
'''Overlap matrices''' are formed as % overlaps of range A on B and B on A.
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'''Partial area''' is the summed area of clusters divided by a single area encompassing all clusters.
 
'''Partial area''' is the summed area of clusters divided by a single area encompassing all clusters.
  
'''Polygons''' are formed by joining edge lines round a set of locations.
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'''Polygons''' are formed by lines round a set of vertices, which may be Locations, corners on Vector maps or equal values interpolated on a Density matrix.
  
 
'''RADA''' TODO
 
'''RADA''' TODO
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'''Vector maps''' are composed of lines and closed shapes defined by a sequence of x,y coordinates.
 
'''Vector maps''' are composed of lines and closed shapes defined by a sequence of x,y coordinates.
  
'''Width of a range''' is the maximum diagonal dimension of a polygon enclosing all the locations.
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'''Width of a range''' is the maximum diagonal dimension of a Convex Hull enclosing all the locations.

Revision as of 18:38, 10 November 2014

Accuracy ellipses are generated round locations from bearing data by some packages (e.g. LOCATE II).

Arithmetic mean is the mean x and y coordinates for a set of Locations.

Autocorrelation analysis estimates the degree of spatio-temporal dependence of Locations.

ASCII is American Standard Code, used to turn bytes into text characters.

Bivariate ellipses are based on Location distributions along a major and a minor axis.

Boundary strips round Locations in hulls have a width of half the tracking resolution.

Byte arrays are Ranges storage format for raster maps; each byte codes for 1 raster.

Centroid distance is from an Arithmetic mean to all the Locations in a cluster.

Cluster analysis joins locations in groups based on the Nearest neighbour distances between them.

Core denotes one or more high areas of high Location density in a range.

Contour analysis plots Isolines across a Density matrix to represent either on a probabilistic or Location-inclusive Utilisation distribution.

CSV files are composed of Comma Separated Values (other separators are Break/Space and Tab).

Density matrix values are estimated at intersections of an arbitrary grid in Contour analyses.

Dispersal detection provides an objective estimate of when animals leave an area.

Dispersion (in contour analyses) the peak density value (at the range centre location) divided by the standard deviation of the density value across all the locations.

Edge denotes an outline estimated round locations as a polygon or by contouring.

Ellipses include circles.

Ellipse asymmetry is the ratio of the standard deviations along the major and minor axes.

End date in a Kaplan Meier Survival analysis is the date to which survival should be estimated; by default the last date for any animal, it may be set earlier to ensure an adequate sample in the last interval or to analyses a particular season; see also Start date.

Focal site denotes an attraction point in a range, such as a den or nest.

ESRI is the Environmental Systems Research Institute, which supplies GIS software.

Grid cells are as wide as the location resolution.

GIS is a Geographic Information System.

Grid edges are the eastmost, westmost, northmost and southmost coordinates in sets of locations.

Gridascii files are of ASCII values used by ESRI soft for transferring raster map data.

Habitat points are x,y coordinates associated with habitat codes for different trees, etc.

Habitat shapes are formed from a clockwise set of x,y values with the same start and end point.

Harmonic mean analyses are based on the inverse reciprocal mean of distances.

hRef is the reference smoothing parameter in kernel analyses ( SD / sixth root N )

Hull is a polygon with vertices fitted to a set of locations; a Convex Hull has all external angles greater than 180°.

Incremental analysis estimates and plots the change in range area as successive locations are added.

Isolines of equal location density are created during contour analysis and converted to polygons.

Jacob's index has values between -1 and +1 to indicate attraction versus avoidance.

Kaplan Meier Survival plots survival in intervals between Start dates and End dates in .srv files and tests for significance between cohorts.

Kernel analyses are based on estimating location density as functions of distance.

Kurtosis is an index of spread in the density distribution during harmonic mean & kernel contouring.

Location denotes x,y coordinates of an observation, often with associated qualifying variables.

Location centring is computed during harmonic mean contouring to remove location resolution effects.

Location resolution is the smallest distance that can be recorded between adjacent locations.

Location Qualifying Variables (LQVs) are time, activity, habitat, values associated with x,y coordinates.

Nearest Neighbour distances are the minimum distance between spatially separate locations.

Neighbour Linkage analyses estimate Hulls round locations whose individual or summed Nearest neighbour distances do not exceed a certain value.

Objective Cores exclude Locations more isolated than a criterion distance based on the distribution of all Nearest Neighbour distances.

OREP Objective Restrictive Edge Polygons have maximum peripheral edge distances less than a criterion based on the distribution of all Nearest Neighbour distances.

Outlier locations are those more isolated than a criterion distance based on the distribution of all Nearest Neighbour distances.

Overlap matrices are formed as % overlaps of range A on B and B on A.

Partial area is the summed area of clusters divided by a single area encompassing all clusters.

Polygons are formed by lines round a set of vertices, which may be Locations, corners on Vector maps or equal values interpolated on a Density matrix.

RADA TODO

Range variables are seven values that code ID, age, sex, month, year and focal site coordinates.

Raster maps are composed of equal-size rectangles with different habitat codes.

Schoener's index increases from 0 with decreasing spatio-temporal dependence between locations (= mean squared distances between locations / mean squared distance from each location to the arithmetic activity centre).

Shape files are the standard polygon format in an ESRI GIS.

Skew in the location density distribution is estimated during harmonic mean & kernel contouring ( the Euclidean distance between the arithmetic mean centre and the location with the peak density value, divided by the standard deviation of the density value across all the locations).

Simpson's index increases from 1 with increasing diversity between clusters.

Smoothing factor modulates the density function in kernel analyses to improve fit of contours.

Spread of a range is the grand mean of distances between all the locations.

Start date in a Kaplan Meier Survival analysis is the date from which survival should be estimated; by default the first date for any animal, it may be set later to ensure an adequate sample in the first interval or to analyses a particular season; see also End date.

Tracking resolution is the smallest distance that can be recorded between adjacent locations.

Utilisation plots are of range area against percentages of Location inclusion or location density.

UTM stands for Universal Transverse Mercator is a two-dimensional Cartesian coordinate system to give locations on the surface of the Earth.

Vector maps are composed of lines and closed shapes defined by a sequence of x,y coordinates.

Width of a range is the maximum diagonal dimension of a Convex Hull enclosing all the locations.