Nonparametric Density Estimation and Galaxy Clustering

摘要

We estimate the number density of galaxy clusters as a function of z, redshift. Nonparametric density estimation is used to estimate the galaxy density f given z and then the connected components of the level set {f(-|.z) > <5C} are extracted as clusters. The parameter 5C is estimated by matching the number density to the Press-Schechter model using a goodness-of-fit criterion. Since 5C is itself a function of a cosmological parameter, this leads to a confidence interval for the parameter.