moral variables. How are personal crime and property related to each other, and to suicide, donations to the poor, illegitimate births, wealth, and so forth? How do different types of crimes vary with age of the accused? Statistical methods (correlation and regression) were still in their infancy, so Guerry relied on graphic comparisons of maps and semi-graphic tables. Shown below are three of the six thematic maps that Guerry included in his Essay. Suicide In addition to a map of France showing rates of suicide by department, Guerry collected all the suicide notes found by the police in Paris over a four-year period. He classified these by the apparent motive expressed for taking one's life, perhaps the first content analysis in the social sciences. Ordonnateur statistique Around 1851, Guerry invented the Ordonnateur Statistique, probably the first mechanical device designed to aid in statistical calculations and the assessment of relationships among moral variables. This device is now known to have been used for sorting one target variable (e.g., crimes of different types) in relation to other possibly explanatory variables (e.g., population density). Polar area diagram In 1829, Guerry invented a new graphic form, the polar area diagram to show variations in weather and other phenomena over calendar cycles. This variation of the pie chart uses equi-angular sectors of differing radii, in contrast to the pie chart that uses sectors with varying angle, but equal radii. The polar area diagram is often mistakenly credited to Florence Nightingale, who used it to great effect to illustrate needless mortality in the Crimean War due to unsanitary medical conditions. Nightingale most probably got the idea from William Farr, who in turn was acquainted with Guerry's work. Other activities Guerry also resided in Beaumont-sur-Dême, where he was mayor of the village from 1846 to 1855. Major works Balbi, Adriano, and André-Michel Guerry. 1829. Statistique comparée de l'état de l'instruction et du nombre des crimes dans les divers arrondissements des Académies et des Cours Royales de France. Paris. Image Guerry, André-Michel. 1829. Mémoire sur les variations méterologiques comparées aux phénomènes physiologiques. Annales d'Hygiène Publique et de Médecine Légal 1:228. Guerry, André-Michel. 1832. Statistique comparée de l’état de l’instruction et du nombre des crimes. Paris: Everat Gallica Guerry, André-Michel. 1832. Motifs des crimes capitaux, d’apres les comptes de l’administration de la justice criminelle. Annales d’Hygiène Publique et de Médecine Légale, 8, 335–346. Guerry, André-Michel. 1833. Essai sur la