title: Bias in graduated life table functions.
abstract: Survival proportions and expectations of life estimated directly from observed crude mortality rates are usually unbiased. Estimates of survival proportions and expectations of life obtained from graduated mortality rates at individual ages tend to be positively biased, although the actual bias is small for reasonably large experiences.
mesh_terms: D006801:Humans; D008017:Life Expectancy; D009026:Mortality; D011336:Probability