QCAGUI (version 2.4)

XYplot: Create an XY plot

Description

This function creates an XY plot from the first two columns of a dataframe/matrix, or from two separate vectors of numeric values.

Usage

XYplot(x, y, data, relation = "nec", mguides = TRUE, jitter = FALSE, clabels = NULL, ...)

Arguments

x

Character, the name of the column from the data for the X axis, or the coordinates of points in the plot (either a matrix/dataframe with at least two columns, or a vector of values for the X axis).

y

Character, the name of the column from the data for the Y axis, or the Y coordinates of points in the plot, optional if x is a matrix/dataframe.

data

A calibrated dataset, only if x and y are names.

relation

The set relation to Y, either "nec" (default) or "suf".

mguides

Logical, print the middle guides.

jitter

Logical, jitter the points.

clabels

A vector of case labels with the same length as x and y.

...

Other graphical parameters from par

Value

A list of x and y values, especially useful when the points are jittered.

Details

If x is a dataframe or a matrix, the X and Y labels will be taken from the column names of x, otherwise they will be inferred from the names of the x and y objects that are passed to this function.

x can also be a string containing either the name of the column for the X axis, or two column names separated by a comma, referring to the X and Y axis respectively. When x contains both X and Y column names, the next argument will be considered as the data.

If data is provided, and the names of the X and Y columns are valid R statements, quoting them is not even necessary and they can be negated using either a tilde ~ or 1 - .

The numeric values should be restricted between 0 and 1, otherwise an error is generated.

The XY plot will also produce inclusion and coverage scores for a sufficiency or a necessity relation, along with PRI for a sufficiency relation and RoN (relevance of necessity) for a necessity relation.

The argument ... is used to pass various graphical parameters for the various plotting functions used.

The points have a default cex (character expansion) value of 0.8, and a default pch value of 21 (filled points), which can be modified accordingly (for example with value 1 of empty points). When pch = 21, the color for the margins of the points can be specified via the argumen col, while the argument bg will determine the fill color of the points.

The axis labels have a default cex.axis value of 0.8, which affects both the tickmarks labels and the axis labels.

When jittering the points, default values of 0.01 are used for the parameters factor and amount, on both horizontal and vertical axes.

References

Cebotari, V.; Vink, M.P. (2013) “A Configurational Analysis of Ethnic Protest in Europe”. International Journal of Comparative Sociology vol.54, no.4, pp.298-324.

Schneider, C. and Wagemann, C. (2012) Set-Theoretic Metods for the Social Sciences. A Guide to Qualitative Comparative Analysis. Cambridge: Cambridge University Press.

See Also

par, text, jitter

Examples

if (require("QCA")) {

# Cebotari & Vink (2013)
data(CVF)

# necessity relation between NATPRIDE and PROTEST
XYplot(CVF[, 5:6])

# same using two numeric vectors
XYplot(CVF$NATPRIDE, CVF$PROTEST)

# same using two column names
XYplot("NATPRIDE", "PROTEST", data = CVF)

# or using one string containing both
XYplot("NATPRIDE, PROTEST", data = CVF)

# since they are valid R statements, it works even without quotes
# (this only works in normal R console, not in the GUI version)
XYplot(NATPRIDE, PROTEST, data = CVF)

# negating the X axis, using numeric vectors
XYplot(1 - CVF$NATPRIDE, CVF$PROTEST)

# same thing using quotes
XYplot("1 - NATPRIDE, PROTEST", data = CVF)

# using tilde for negation
XYplot("~NATPRIDE, PROTEST", data = CVF)

# different color for the points
XYplot("~NATPRIDE, PROTEST", data = CVF, col = "blue")

# using a different character expansion for the axes
XYplot("~NATPRIDE, PROTEST", data = CVF, cex.axis = 0.9)

# custom axis labels
XYplot("~NATPRIDE, PROTEST", data = CVF, xlab = "Negation of NATPRIDE",
       ylab = "Outcome: PROTEST")

# sufficiency relation
XYplot("~NATPRIDE, PROTEST", data = CVF, relation = "suf")

# jitter the points
XYplot("~NATPRIDE, PROTEST", data = CVF, jitter = TRUE)

# jitter with more amount
XYplot("~NATPRIDE, PROTEST", data = CVF, jitter = TRUE, amount = 0.02)

# adding labels to points
XYplot("~NATPRIDE, PROTEST", data = CVF, jitter = TRUE, cex = 0.8,
       clabels = rownames(CVF))

# or just the row numbers, since the row names are too long
XYplot("~NATPRIDE, PROTEST", data = CVF, jitter = TRUE, cex = 0.8,
       clabels = seq(nrow(CVF)))

}