This polar area diagram was published by Florence Nightingale (1820–1910) in Notes on Matters Affecting the Health, Efficiency, and Hospital Administration of the British Army. It displays the number of deaths in three categories: preventable diseases (blue), wounds (red), and other causes (black). Sent to Queen Victoria, this publication was designed to improve medical practice in the field.
Florence Nightingale exhibited a gift for mathematics from an early age and excelled in the subject under the tutelage of her father. Later, Nightingale became a pioneer in the visual presentation of information and statistical graphics. She used methods such as the pie chart, which had first been developed by William Playfair in 1801. While taken for granted now, it was at the time a relatively novel method of presenting data.
Indeed, Nightingale is described as "a true pioneer in the graphical representation of statistics", and is credited with developing a form of the pie chart now known as the polar area diagram, or occasionally the Nightingale rose diagram, equivalent to a modern circular histogram, to illustrate seasonal sources of patient mortality in the military field hospital she managed. Nightingale called a compilation of such diagrams a "coxcomb", but later that term would frequently be used for the individual diagrams. She made extensive use of coxcombs to present reports on the nature and magnitude of the conditions of medical care in the Crimean War to Members of Parliament and civil servants who would have been unlikely to read or understand traditional statistical reports. In 1859, Nightingale was elected the first female member of the Royal Statistical Society. In 1874 she became an honorary member of the American Statistical Association.
Information from Wikipedia.
Hugh Small's article "Florence Nightingale's Statistical Diagrams" is also available.
