galaxy {multimode}

Velocities of galaxies diverging away from our own galaxy

Description

This dataset contains the velocities in km/sec of different galaxies from the unfilled survey of the Corona Borealis region.

Usage

data(galaxy)

Format

galaxy includes the original measures in Roeder (1990). galaxyrg includes the data provided in the Supplementary material of Richardson and Green (1997), where the velocities are divided by 1000 and the 78th observation was replaced by 26690 km/sec. galaxyp add a measurement of 5607 km/sec included in Postman et al. (1986).

Details

This is a classic example for determining the number of modes.

Source

Obtained from the Table 1 of Postman et al. (1986), Table 1 of Roeder (1990) and the Supplementary material of Richardson and Green (1997), available in http://www.stats.bris.ac.uk/~peter/mixdata.

References

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.

Richardson, S. and Green, P. J. (1997). On Bayesian analysis of mixtures with unknown number of components (with discussion). Journal of the Royal Statistical Society, Series B, 59, 731–792.

Roeder, K. (1990). Density estimation with confidence sets exemplified by superclusters and voids in the galaxies. Journal of the American Statistical Association, 85, 617–624.

Examples

data("galaxy")
# Mode tree between the critical bandwidths for one and six modes
modetree(galaxy,cbw1=1,cbw2=6)