This dataset was compiled from the Maryland Certificates of Freedom, which were produced between 1806 and 1864 for individuals born between 1742 and 1851. The aim of these certificates was to provide legal proof that a black person was free and not a runaway slave. Consequently, Komlos (1992) studied aspects of selectivity related to which groups of slaves received freedom (or were born free). The dataset contains nearly 15,000 observations, of which more than half were female. It also contains data on the county of birth (within Maryland) for each individual, their skin tone, and whether or not they were born a slave. No age restrictions were applied, meaning that the dataset includes individuals between the ages of 1 and 80, so some were still growing or had already undergone shrinking at the age of measurement. Original measurements were taken in British inches.