A directional counterpart of Ripley's \(K\) function,
 in which pairs of points are counted only when the
 vector joining the pair happens to
 lie in a particular range of angles.

Ksector

Functionality for exploratory data analysis and nonparametric analysis of
spatial data, mainly spatial point patterns,
in the 'spatstat' family of packages.
(Excludes analysis of spatial data on a linear network,
which is covered by the separate package 'spatstat.linnet'.)
Methods include quadrat counts, K-functions and their simulation envelopes, nearest neighbour distance and empty space statistics, Fry plots, pair correlation function, kernel smoothed intensity, relative risk estimation with cross-validated bandwidth selection, mark correlation functions, segregation indices, mark dependence diagnostics, and kernel estimates of covariate effects. Formal hypothesis tests of random pattern (chi-squared, Kolmogorov-Smirnov, Monte Carlo, Diggle-Cressie-Loosmore-Ford, Dao-Genton, two-stage Monte Carlo) and tests for covariate effects (Cox-Berman-Waller-Lawson, Kolmogorov-Smirnov, ANOVA) are also supported.

Adrian Baddeley

spatstat.explore

Exploratory Data Analysis for the 'spatstat' Family

Rolf Turner

Ege Rubak

Kasper Klitgaard Berthelsen

Warick Brown

Achmad Choiruddin

Ya-Mei Chang

Jean-Francois Coeurjolly

Lucia Cobo Sanchez

Ottmar Cronie

Tilman Davies

Julian Gilbey

Jonatan Gonzalez

Yongtao Guan

Ute Hahn

Martin Hazelton

Kassel Hingee

Abdollah Jalilian

Frederic Lavancier

Marie-Colette van Lieshout

Greg McSwiggan

Robin K Milne

Tuomas Rajala

Suman Rakshit

Dominic Schuhmacher

Rasmus Plenge Waagepetersen

Hangsheng Wang

Tingting Zhan

Ksector function

Sector K-function — Ksector

<dl>

 <dt>X</dt>
<dd>The observed point pattern, 
 from which an estimate of \(K(r)\) will be computed.
 An object of class <code>"ppp"</code>, or data
 in any format acceptable to <code>as.ppp()</code>.</dd>

 <dt>begin,end</dt>
<dd>Numeric values giving the range of angles inside which
 points will be counted. Angles are measured in degrees
 (if <code>units="degrees"</code>, the default) or radians
 (if <code>units="radians"</code>) anti-clockwise from the positive \(x\)-axis.</dd>

 <dt>...</dt>
<dd>Ignored.</dd>

 <dt>units</dt>
<dd>Units in which the angles <code>begin</code> and <code>end</code> are expressed.</dd>

 <dt>r</dt>
<dd>Optional. Vector of values for the argument \(r\) at which \(K(r)\) 
 should be evaluated. Users are advised not to specify this
 argument; there is a sensible default.</dd>

 <dt>breaks</dt>
<dd>This argument is for internal use only.</dd>

 <dt>rmax</dt>
<dd>Optional. Maximum desired value of the argument \(r\).
 A single numeric value. There is a sensible default.</dd>

 <dt>correction</dt>
<dd>Optional. A character vector containing any selection of the
 options <code>"none"</code>, <code>"border"</code>, <code>"bord.modif"</code>,
 <code>"isotropic"</code>, <code>"Ripley"</code>, <code>"translate"</code>,
 <code>"translation"</code>, <code>"none"</code>, <code>"good"</code> or <code>"best"</code>.
 It specifies the edge correction(s) to be applied.
 Alternatively <code>correction="all"</code> selects all options.</dd>

 <dt>domain</dt>
<dd>Optional window. The first point \(x_i\) of each pair of points
 will be constrained to lie in <code>domain</code>.</dd>

 <dt>ratio</dt>
<dd>Logical. 
 If <code>TRUE</code>, the numerator and denominator of
 each edge-corrected estimate will also be saved,
 for use in analysing replicated point patterns.</dd>

 <dt>verbose</dt>
<dd>Logical value indicating whether to print progress reports
 and warnings.</dd>

</dl>

Arguments

Adrian Baddeley <a href='mailto:Adrian.Baddeley@curtin.edu.au'>Adrian.Baddeley@curtin.edu.au</a> 
 
Rolf Turner <a href='mailto:rolfturner@posteo.net'>rolfturner@posteo.net</a> 
and Ege Rubak <a href='mailto:rubak@math.aau.dk'>rubak@math.aau.dk</a>

Author

Sector K-function

Ksector: Sector K-function

Description

Usage

Arguments

Value

Details

See Also

Examples