plot.fechner {fechner} | R Documentation |
S3 method to plot objects of the class fechner
.
## S3 method for class 'fechner': plot(x, level = 1, ...)
x |
a required object of class fechner , obtained from a
call to the function fechner . |
level |
an optional numeric, integer-valued and greater-equal 1, giving the level of comparison of the S-index and the overall Fechnerian distance G. |
... |
further arguments to be passed to or from other methods. They are ignored in this function. |
The plot
method graphs the results obtained from Fechnerian
scaling analyses. It produces a scatterplot of the overall
Fechnerian distance G versus the S-index, with rugs
added to the axes and jittered (amount = 0.01
of noise) to
accommodate ties in the S-index and G values. The added
diagonal line y = x is for visual inspection of the deviations
of the two types of values.
The level
of comparison refers to the minimum number of edges
in geodesic loops plus 1. That is, choosing level n
means that comparison involves only those S-index and G
values that have geodesic loops containing not less than n - 1
edges.
If there are no (off-diagonal) pairs of stimuli with geodesic loops
containing at least level
- 1 edges (in this case a
plot is not possible), plot.fechner
stops with an error
message.
If the arguments x
and level
are of required types,
and if there are (off-diagonal) pairs of stimuli with geodesic loops
containing at least level
- 1 edges,
plot.fechner
produces a plot, and invisibly returns
NULL
.
Thomas Kiefer thomas.kiefer@student.uni-augsburg.de, Ali Uenlue ali.uenlue@math.uni-augsburg.de. Based on original MATLAB source by Ehtibar N. Dzhafarov.
Dzhafarov, E. N. and Colonius, H. (2006) Reconstructing distances among objects from their discriminability. Psychometrika, 71, 365–386.
Dzhafarov, E. N. and Colonius, H. (2007) Dissimilarity cumulation theory and subjective metrics. Journal of Mathematical Psychology, 51, 290–304.
Kiefer, T. and Uenlue, A. and Dzhafarov, E. N. (2009) Fechnerian scaling in R: The package fechner. Manuscript submitted for publication. http://www.math.uni-augsburg.de/~uenlueal/
print.fechner
, the S3 method for printing objects of
the class fechner
; summary.fechner
, the S3
method for summarizing objects of the class fechner
, which
creates objects of the class summary.fechner
;
print.summary.fechner
, the S3 method for printing
objects of the class summary.fechner
; fechner
,
the main function for Fechnerian scaling, which creates objects of
the class fechner
. See also fechner-package
for general information about this package.
## Fechnerian scaling of dataset wish f.scal.wish <- fechner(wish) ## results are plotted for comparison levels 1 and 5 plot(f.scal.wish) plot(f.scal.wish, level = 5)