(x, y, z) coordinates of the location of the tip of a pen during fifty
replications of writing 'Statistical Science' in simplified Chinese at
10 millisecond intervals
Usage
data(StatSciChinese)
Format
a 3-dimensional array of dimensions (601, 50, 3) containing 601
observations of (x, y, z) coordinates of the tip of a pen at 2.5
millisecond intervals for each of 50 repitions of writing 'Statistical
Science' in simplified Chinese.
Details
Xiaochun Li wrote 'Statistical Science' in simplified Chinese 50
times. An infra-red detecting tablet was attached to the tip of the
pen, and a wall-mounted set of three cameras recorded its position 400
times per second with an error level of about 0.5 millimeters. Each
sample required about 6 seconds to produce, and for simplicity, time
was normalized to this interval for all 50 records. The script
requires 50 strokes, with an average time of 120 milliseconds per
stroke. These raw data were shifted and rotated so the numbers more
accruately reflected x and y coordinates relative to the
drawn characters plus vertical distance from the paper.
References
Ramsay, James O. (2000) Functional Components of Variation in
Handwriting, Journal of the American Statistical Association,
95, 9-15.
Examples
data(StatSciChinese)
i <- 3
StatSci1 <- StatSciChinese[, i, ]
# Where does the pen leave the paper?
plot(StatSci1[, 3], type='l')
thresh <- quantile(StatSci1[, 3], .8)
abline(h=thresh)
sel1 <- (StatSci1[, 3] < thresh)
StatSci1[!sel1, 1:2] <- NA
plot(StatSci1[, 1:2], type='l')
mark <- seq(1, 601, 12)
points(StatSci1[mark, 1], StatSci1[mark, 2])