A collection of several geoms to create graphics, using
    'ggplot2' and the Cartesian coordinate system. You use the familiar
    mapping 'Grammar of Graphics' without the need to do another
    transformation into polar coordinates.

An implementation of the generalized graded unfolding model (GGUM) in R, see Roberts, Donoghue, and Laughlin (2000) <doi:10.1177/01466216000241001>). It allows to simulate data sets based on the GGUM. It fits the GGUM and the GUM, and it retrieves item and person parameter estimates. Several plotting functions are available (item and test information functions; item and test characteristic curves; item category response curves). Additionally, there are some functions that facilitate the communication between R and 'GGUM2004'. Finally, a model-fit checking utility, MODFIT(), is also available.

Replace the standard x-axis in 'ggplots' with a combination matrix
  to visualize complex set overlaps. 'UpSet' has introduced a new way to visualize
  the overlap of sets as an alternative to Venn diagrams. 
  This package provides a simple way to produce such plots using 'ggplot2'. 
  In addition it can convert any categorical axis into a combination
  matrix axis.

An easy-to-use way to draw pretty venn diagram by 'ggplot2'.

Easy-to-use functions to generate 2-7 sets Venn or upset plot in publication quality. 
  'ggVennDiagram' plot Venn or upset using well-defined geometry dataset and 'ggplot2'. The shapes of 2-4 sets 
  Venn use circles and ellipses, while the shapes of 4-7 sets Venn use irregular polygons (4 has both forms), which 
  are developed and imported from another package 'venn', authored by Adrian Dusa. We provided internal functions to 
  integrate shape data with user provided sets data, and calculated the geometry of every regions/intersections 
  of them, then separately plot Venn in four components, set edges/labels, and region edges/labels.
  From version 1.0, it is possible to customize these components as you demand in ordinary 'ggplot2' grammar.
  From version 1.4.4, it supports unlimited number of sets, as it can draw a plain upset plot automatically when
  number of sets is more than 7.