Welcome to the Home Page of Gary Sneddon

How to contact me

e-mail address: gsneddon at mun dot ca

Photo Ops From a Previous Life

Check out some photos from a November 23/98 hike to Mallory Cave, right in NCAR's backyard. NOTE: I now longer climb many mountains, or have red hair like this!
Photo 1: The long climb up.
Photo 2: I'm stuck!
Photo 3: At the door of Mallory Cave. (That's me in the black shirt. Please note my hair is much less red now, and much more salt-and-pepper (mostly salt)).
Photo 4: NCAR from Mallory Cave.
Photo 5. The rugged crew.

Teaching Information for Winter 2010: Stats 3411, Stats 4590.

Courses Previously Taught (in addition to those above): Stats 2500, Stats 2501, Stats 2510, Stats 3520, Stats 3521, Stats 3540, Stats 4540/6571, Stats 6590

New Position (Effective August 1, 2010):

  • Faculty member in the Department of Mathematics at Mount Saint Vincent University in Halifax, Nova Scotia.

    Past Position (Jan. 1999-July 2010):

  • Assistant professor in the Department of Mathematics and Statistics at Memorial University of Newfoundland in tropical St. John's.

    Even Earlier Experience

    Check out the NCAR Mesa Lab location in Boulder.

    Research Interests

  • Modelling correlated count data with excess zeros. This is joint work with Tariqul Hasan and Renjun Ma of the University of New Brunswick (UNB), Fredericton.

  • Longitudinal data analysis. This is joint work with Brajendra Sutradhar of Memorial University and Vandna Jowaheer of the University of Mauritius.
  • Methods of smoothing in linear models in which the number of parameters exceeds the number of observations (underdetermined models), and the application of these methods in ocean and climate problems.

    Theses from long ago

  • The title of my PhD thesis is Smoothing Techniques in Underdetermined Linear Models . Click here for my thesis abstract. (Actually, don't click yet. It's not there right now).

    If you're really brave, the whole book is right here, as a gzipped postscript file. (Yes, it is finally there to cure your insomnia!).

  • The title of my MSc thesis is Random Effects in Nonlinear Regression Models. Someday I'll put in a link to the abstract and whole book.


  • Hasan, M.T., Sneddon G. and Ma, R.J. (2009). Pattern-mixture zero-inflated mixed models for longitudinal unbalanced count data with excessive zeros. Biometrical Journal 51, 946-960.

  • Hasan, M. Tariqul and Sneddon, Gary (2009). Zero-Inflated Poisson Regression for Longitudinal Data. Communications in Statistics-Simulation and Computation, 38, 638-653.

  • Jowaheer, V, Sutradhar, B.C. and Sneddon, G. (2009). On familial Poisson mixed models with multi-dimensional random effects. Journal of Statistical Computation and Simulation 79, 1043-1062.

  • Ma, R.J., Hasan, M.T., and Sneddon G. (2009). Modelling heterogeneity in clustered count data with extra zeros using compound Poisson random effect Statistics in Medicine 28, 2356-2369.

  • Hasan, M.T. and Sneddon, G. (2008). Robust correlation structure for multivariate failure time data. Communications in Statistics-Simulation and Computation 37, 1839-1854.

  • Sutradhar, Brajendra C., Jowaheer, Vandna and Sneddon, Gary (2008). On a Unified Generalized Quasi-likelihood Approach for Familial-Longitudinal Non-Stationary Count Data. Scandinavian Journal of Statistics, 35, 597-612.

  • Hasan, M. Tariqul, Sutradhar, Brajendra C. and Sneddon, Gary (2007). On correlation models for longitudinal failure time data. Sankhya: The Indian Journal of Statistics, 69, 548-580.

  • Sneddon, Gary and Sutradhar, B.C. (2004). On semiparametric familial-longitudinal models. Statistics and Probability Letters 69, 369-379.

  • Sneddon, Gary (2000) A statistical perspective on data assimilation in numerical models. Studies in the Atmospheric Sciences, 7-21. Berliner, L. Mark (ed.), Nychka, Douglas (ed.) and Hoar, Timothy (ed.) Springer-Verlag Inc (Berlin; New York).

  • Sneddon, Gary (1999). Smoothing in an Underdetermined Linear Model with Random Explanatory Variables. Canadian Journal of Statistics 27, 63-80.

    Selected Presentations

  • Hasan, M.T., Ma, R. and Sneddon, G. (2009). Modeling heterogeneity in clustered count data with extra zeros using compound Poisson random effect. Statistical Society of Canada Annual Meeting, Vancouver, BC.

  • Sneddon G., Hasan, M.T. and Ma, R. (2009). Modeling longitudinal count data with extra zeros using compound Poisson random effect. Statistical Society of Canada Annual Meeting, Vancouver. BC.

  • Sneddon G., Jowaheer, V. and Sutradhar, B.C. (2009). Maximum QL vs. Generalized Absolute-Deviation Based QL Inferences for Median Regression. ISS 2009, St. John's, NL.

  • Hasan, M. T. and Sneddon, G. (2007). Zero-inflated Poisson regression for longitudinal data. Statistical Society of Canada Annual Meeting, St. John's, NL.

  • Hasan, M. T., Sutradhar, B. C. and Sneddon, G. (2003). Analysing Longitudinal Failure Time Data: Generalized Estimating Equations Approach. Statistical Society of Canada Annual Meeting, Halifax, NS.

  • Sneddon, Gary. Approximating Posterior Distributions in Ensemble Forecasting. Joint Statistical Meetings (ASA), Baltimore MD, August 1999.

  • Sneddon, Gary. An Approach to Smoothing in Underdetermined Regression Models. Seminar Series, Dept. of Statistics, Colorado State University. February 1998.

  • Sneddon, Gary. Smoothing in an Underdetermined Linear Model with Random Explanatory Variables . Annual Meeting of the Statistical Society of Canada, Fredericton, NB, June 1997.


  • October 1997: I completed my PhD in statistics in the department of Mathematics and Statistics at Dalhousie University. My thesis was done under the supervision of Dr. Chris Field. Dalhousie is in Halifax, Nova Scotia.
  • May 1992. MSc in statistics, Dalhousie University. Completed under the supervision of Dr. David Hamilton.
  • May 1990. BSc (honours) from Acadia University in Wolfville, Nova Scotia.
  • Date long since forgotten. I graduated from high school from Sydney Academy in my hometown of Sydney, Nova Scotia.

    Teaching Experience

  • 2004-2005. Teaching ST3540, ST4590 and ST6590 at Memorial.
  • 2003-2004. Taught ST2501, ST3520 and ST4540 at Memorial.
  • 2002-2003. Taught ST2501, ST4590 and ST6590 at Memorial.
  • 2001-2002. Taught ST2501, ST3540 and ST4590 at Memorial.
  • 2000-2001. Taught ST3540, ST4590 and ST6590 at Memorial.
  • 1999-2000. Taught ST2500, ST2501 and ST3540 at Memorial.
  • Winter 1999. Taught ST2510 and ST3521 at Memorial.
  • Sept. 1995-April 1997. Statistics instructor in the Dalhousie Integrated Science Program (Disp).
  • Winter 1997. Lecturer for Statistics 2080, a course in regression and experimental design.

    More details are contained in my cv, another gzipped postscript file. OK, I lied again. It's not there. I'm far too busy with work to update this page much :-)

    NCAR Links

    Last updated August 9, 2010.

    gary dot sneddon at msvu dot ca