pub fn galaxies() -> Result<DataFrame, PolarsError>Expand description
§Velocities for 82 Galaxies
§Description:
A numeric vector of velocities in km/sec of 82 galaxies from 6 well-separated conic sections of an ‘unfilled’ survey of the Corona Borealis region. Multimodality in such surveys is evidence for voids and superclusters in the far universe.
§Usage:
galaxies
§Note:
There is an 83rd measurement of 5607 km/sec in the Postman et al. paper which is omitted in Roeder (1990) and from the dataset here.
There is also a typo: this dataset has 78th observation 26690 which should be 26960.
§Source:
Roeder, K. (1990) Density estimation with confidence sets exemplified by superclusters and voids in galaxies. Journal of the American Statistical Association 85, 617-624.
Postman, M., Huchra, J. P. and Geller, M. J. (1986) Probes of large-scale structures in the Corona Borealis region. Astronomical Journal 92, 1238-1247.
§References:
Venables, W. N. and Ripley, B. D. (2002) Modern Applied Statistics with S. Fourth edition. Springer.
§Examples:
gal <- galaxies/1000
c(width.SJ(gal, method = "dpi"), width.SJ(gal))
plot(x = c(0, 40), y = c(0, 0.3), type = "n", bty = "l",
xlab = "velocity of galaxy (1000km/s)", ylab = "density")
rug(gal)
lines(density(gal, width = 3.25, n = 200), lty = 1)
lines(density(gal, width = 2.56, n = 200), lty = 3)