Research interests

My faculty research directory entry

My research interests lie in three separate but inter-related areas. They are

A fourth academic area in which I have an interest in is that of statistics, science and public policy.> I have written a few essays on these general topics.

These and other selected papers and talks are made available below.

Graduate Students

I have been fortunate in being able to supervise a number of students in their research over the years. Information on these students, including the topic of their work and in some cases the work itself, may be found here.


Selected papers and talks

Data visualization, data mining, programming environments

  • Discussion of Per Andersen's ``Goodness of fit in event history analysis using pseudo-observations'' as presented at the Jack Kalbfleisch and Jerry Lawless Conference in May, 2010 at the University of Waterloo. This is a QuickTime movie of my presentation. NOTE: This could take some time to load ( is approx 20 MB) and depende on Per's paper for understanding.
  • Presentation Graphics An important part of data visualization is the development of effective presentation graphics (as opposed to analytic or exploratory graphics). This is the principal focus of Tufte's work. Here are some presentation graphics we developed to communicate the extremely small probabilities associated with state lotteries. Figures here are based on Canadian Lotteries but could easily be adapted for others.
  • Applications of Graph Theory to Data Visualization This is joint work with Catherine Hurley of the National University of Ireland, Maynooth. Best viewed in chronological order.
  • Picturing Probability or Eikosograms
  • Clustering
  • Quail See also the Quail website
  • Statistics, Science and Public Policy

    This covers wide variety of topics. The essays and talks here are based on invited presentations at the series of small invitation only conferences developed by Prof. A. Herzberg in honour of her father the nobel prize (Physics) winner Dr. Gerhard Herzberg. The conferences are on Statistics, Science and Public Policy and have, for the most part, been held at Queen's University's Herstmonceux Castle in Hailsham England.

    Each year had a different theme and speakers were asked to address particular subjects in keeping with the theme.

    Each of these appear as a separate chapter in the series of books Statistics, Science, and Public Policy which may be purchased by contacting Prof. A. Herzberg of Queen's University in Kingston, Canada.

    Scientific Method, statistical foundations

    Some applications

    Selected Early Work

    Teaching, Education

    Sept. 2008.

    rwoldford (at)