Figure 3
From: The Seasonality of Acute Attack of Primary Angle-Closure Glaucoma in Beijing, China
Angular plot (rose plot) of the dates of onset of primary angle-closure glaucoma (PACG), and probability density functions of the von Mises distribution. (A) The 360 angles correspond to dates of the 365 days in a year. The segments are ordered from January to December corresponding from 0°to 360° (anticlockwise) starting due east in each rose plot. Corresponding peak onset and magnitude of each rose plot is indicated by the arrow analogues, which point to different angles (Above: all cases; left below: male data; right below: female data). (B) R is the magnitude of the peak estimated by the length of the mean resultant; μ stands for mean direction. The functions with μ = 0°, for κ = 0.5, 1, 2 and 4, were used to better understand the shape changes in the application of von Mises distribution9.
