neighbourmap: Neighbour plot and map
In GeoXp: Interactive exploratory spatial data analysis

Description Usage Arguments Details Value Note Author(s) References See Also Examples

The function neighbourmap() identifies spatial outliers by comparing a variable value for a particular site with these of its neighbouring sites. It draws a scatterplot of the values of the variable at neighbouring sites for a neighbourhood structure given by a binary weight matrix W and links this scatterplot with a map.

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neighbourmap(sp.obj, name.var, nb.obj, lin.reg=TRUE,
names.attr=names(sp.obj), criteria=NULL, carte=NULL, identify=FALSE, cex.lab=0.8,
pch=16, col="lightblue3", xlab="", ylab="", axes=FALSE, lablong="", lablat="")

`sp.obj`	object of class extending Spatial-class
`name.var`	a character; attribute name or column number in attribute table
`nb.obj`	object of class nb
`lin.reg`	If TRUE, drawing the linear curve y=x
`names.attr`	names to use in panel (if different from the names of variable used in sp.obj)
`criteria`	a vector of boolean of size the number of spatial units, which permit to represent preselected sites with a cross, using the tcltk window
`carte`	matrix with 2 columns for drawing spatial polygonal contours : x and y coordinates of the vertices of the polygon
`identify`	if not FALSE, identify plotted objects (currently only working for points plots). Labels for identification are the row.names of the attribute table row.names(as.data.frame(sp.obj)).
`cex.lab`	character size of label
`pch`	16 by default, symbol for selected points
`col`	"lightblue3" by default, color of bars on the histogram
`xlab`	a title for the graphic x-axis
`ylab`	a title for the graphic y-axis
`axes`	a boolean with TRUE for drawing axes on the map
`lablong`	name of the x-axis that will be printed on the map
`lablat`	name of the y-axis that will be printed on the map

For a selected site j on the map, are represented on the map its neighbors, and on the graph, on the x-axis the value of var for this site, and in y-axis, the values of var for the neighbouring sites of j. For a selected point on the graph, the corresponding pair of sites is represented on the map with a link.

In the case where user click on save results button, a matrix of integer is created as a global variable in last.select object. It corresponds to the numbers of spatial unit corresponding to couple of sites selected just before leaving the Tk window.

When user selects sites on the graph or on the map, he cannot add a selection by using the other graphic.

Aragon Y., Thomas-Agnan C., Ruiz-Gazen A., Laurent T., Robidou L.

Thibault Laurent, Anne Ruiz-Gazen, Christine Thomas-Agnan (2012), GeoXp: An R Package for Exploratory Spatial Data Analysis. Journal of Statistical Software, 47(2), 1-23.

Roger S.Bivand, Edzer J.Pebesma, Virgilio Gomez-Rubio (2009), Applied Spatial Data Analysis with R, Springer.

moranplotmap,makeneighborsw,normw,nonormmoran

###
# columbus
require("maptools")
example(columbus)

# example of use of neighbourmap
neighbourmap(columbus, "CRIME", col.gal.nb,
criteria=(columbus@data$CRIME>mean(columbus@data$CRIME)))

###
# data immob
data(immob)

# change names of individuals
row.names(immob) <- immob$Nom

# immob is a data.frame object. We have to create
# a Spatial object, by using first the longitude and latitude
# to create Spatial Points object ...
immob.sp = SpatialPoints(cbind(immob$longitude,immob$latitude))
# ... and then by integrating other variables to create SpatialPointsDataFrame
immob.spdf = SpatialPointsDataFrame(immob.sp, immob)
# For more details, see vignette('sp', package="sp")

# optional : we add some contours that don't correspond to the spatial unit
# but are nice for mapping
midiP <- readShapePoly(system.file("shapes/region.shp", package="GeoXp")[1])
cont_midiP<-spdf2list(midiP[-c(22,23),])$poly

# A spatial weight matrix based on triangulation Delaunay
W.nb<-tri2nb(cbind(immob$longitude,immob$latitude))

# example of use of neighbourmap
neighbourmap(immob.spdf,"prix.vente", W.nb, identify=TRUE, cex.lab=0.5,
carte=cont_midiP)