Introduction. The social significance of official statistics -- The BLS and the underestimation of unemployment -- The CDC and the overestimation of life expectancy -- The FBI and the miscalculation of crime -- The census bureau and the decennial undercount -- Why official statistics matter.

There are many models in the current statistical literature for making inferences based on samples selected from a finite population. Parametric models may be problematic because statistical inference is sensitive to parametric assumptions. The Dirichlet process (DP) prior is very flexible and...