EZ-ROSE: a computer program for equal-area circular histograms and statistical analysis of two-dimensional vectorial data

Abstract

EZ-ROSE 1.0 is a computer program for the statistical analysis of populations of two-dimensional vectorial data and their presentation in equal-area rose diagrams. The program is implemented as a Microsoft® Excel workbook containing worksheets for the input of directional (circular) or lineational (semi-circular) data and their automatic processing, which includes the calculation of a frequency distribution for a selected class width, statistical analysis, and the construction of a rose diagram in CorelDraw™. The statistical analysis involves tests of uniformity for the vectorial population distribution, such as the nonparametric Kuiper and Watson tests and the parametric Rayleigh test. The statistics calculated include the vector mean, its magnitude (length) and strength (data concentration); the Batschelet circular standard deviation as an alternative measure of vectorial concentration; and a confidence sector for the vector mean. The statistics together with the frequency data are used to prepare a Corel Script™ file that contains all the necessary instructions to draw automatically an equal-area circular frequency histogram (rose diagram) in CorelDraw™. The advantages of EZ-ROSE, compared to other software for circular statistics, are: (1) the ability to use an equal-area scale in rose diagrams; (2) the wide range of tools for a comprehensive statistical analysis; (3) the ease of use, as Microsoft® Excel and CorelDraw™ are widely known to users of Microsoft® Windows; and (4) the high degree of flexibility due to the application of Microsoft® Excel and CorelDraw™, which offer a whole range of tools for possible addition of other statistical methods and changes of the rose-diagram layout.