morsecodes
Rothkopf Morse Code Data
A standard data set for Multidimensional Scaling (MDS) obtained by Rothkopf based on the confusion rates observed by exposing subjects to pairs of morse codes.
- Keywords
- datasets
Usage
data(morsecodes)Details
The raw data from the XGvis directory may be read as
mc.raw <- as.matrix(read.table("....xgobi/data_xgvis/morsecodes.raw"))
dimnames(mc.raw) <- NULL; storage.mode(mc.raw) <- "integer"
morsecodes.raw <- mc.raw.
The *.dist matrix is produced from the raw data by
mc.sim <- (mc.raw + t(mc.raw))/2 ; ds <- diag(mc.sim)
morsecodes.dist <- rep(ds,36) + rep(ds,rep(36,36)) - 2*mc.sim,
i.e., $d[i,j] := s[i,i] +
s[j,j] - 2 * s[i,j]$.
Format
9 data sets used for analyzing the data in XGvis and XGobi.
morsecodes.raw |
| 36 x 36 raw data of confusion rates |
morsecodes.dist |
| 36 x 36 dissimilarity matrix |
morsecodes.pos |
| 36 x 10 initial configuration |
morsecodes.colors |
| 36 point colors |
morsecodes.glyphs |
| 36 point glyphs |
morsecodes.lines |
| 33 lines |
morsecodes.linecolors |
| 33 line colors |
morsecodes.row |
| 36 x 2 matrix of (letter, morsecode) |
Source
Contained in the ‘data\_xgvis’ subdirectory of the XGobi and XGvis source bundle, available via http://www.research.att.com/areas/stat/xgobi/index.html#download.
References
A. Buja, D. F. Swayne, M. Littman, & N. Dean (1998). XGvis: Interactive Data Visualization with Multidimensional Scaling. http://www.research.att.com/areas/stat/xgobi/xgvis98.ps.gz.
Examples
data(morsecodes)
ls.str(pat="^morsecode")
morsecodes.row # remember what you learned in...
## real row names
(mc.row <- paste(morsecodes.row[,1], morsecodes.row[,2]))[1:8]
image(1:36, 1:36, morsecodes.raw, main="`morsecodes' raw confusion rates")
text(1:36,1:36, morsecodes.row[,1])
##--> help(xgvis) for running multidimensional scaling (MDS) and XGobi on these