### Yale University

Department of Statistics

Seminar

#### Monday, January 22, 1995

Professor Leland Wilkinson

SPSS Inc. &

Department of Statistics, NorthWestern University

Seminar to be held in Room 107, 24 Hillhouse at 4:15 pm

Statistical and technical graphs can be viewed as collections of graphical
elements organized by a set of rules. These elements consist of data-based
objects such as clouds, smoothers, and partitions, as well as annotation and
text. A relatively powerful set of rules can be derived from a simple
algebra embedded in a context. The algebra is similar to ones used for
specifying tables. The context involves dimensionality, coordinate systems,
and other aspects related to the display area.
Two systems will be used to demonstrate some of these ideas in software: An
alpha version of SYSTAT 6 for Windows, and a Smalltalk prototype of a
graphical system under development for SPSS Version 8.