velo: Rotational Velocity of Stars


A sample of rotational velocities of stars from Hoffleit and Warren (1991) similar to that previosly considered by Pal, Woodroofe and Meyer (2007) and used by Koenker and Mizera (2010). The demo(velo) illustrates fitted densities for three relatively weak concavity constraints corresponding to -1/sqrt(f), -1/f and -1/f^2 constrained to be concave. Note that last of these pushes the optimization methods about as far as they can do.




A numeric vector with 3933 observations on one variable.


Hoffleit, D. and Warren, W. H. (1991). The Bright Star Catalog (5th ed.). Yale University Observatory, New Haven.


Pal, J. K., Woodroofe, M. and Meyer, M. (2007). Estimating a Polya frequency function. In Complex Datasets and Inverse Problems: Tomography, Networks and Beyond, (R. Liu, W. Strawderman, and C.-H. Zhang, eds.). IMS Lecture Notes-Monograph Series 54 239-249. Institute of Mathematical Statistics. Koenker, R. and Mizera, I. (2010) Quasi-Concave Density Estimation, Annals of Statistics, 38, 2998-3027.

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