Ruth Davidson

I am a Ph.D. candidate in the math department at North Carolina State University in Raleigh, NC.

Office: SAS Hall Room 3145, Contact: redavids at ncsu dot edu



My areas of research interest are mathematical phylogenetics and applied geometric combinatorics.

My advisors are Patricia Hersh and Seth Sullivant.


Towards a shellability proof of a hypergeometric identity. In preparation.

With Seth Sullivant: Distance-based phylogenetic methods around a polytomy. To appear in IEEE/ACM Transactions on Computational Biology and Bioinformatics. Associated Software.

With Patricia Hersh: "A lexicographic shellability characterization of geometric lattices" Journal of Combinatorial Theory, Series A 123 (2014), no. 1: 8-13.

With Seth Sullivant: "Polyhedral Combinatorics of UPGMA Cones" Advances in Applied Math 50 (2013), no. 2, 327-338. Supplementary Materials.


Some Talks and Posters

Slides for JMM 2014 1/15/14

Slides for "Distance-Based Phylogenetic Methods Near a Polytomy" 10/12/13 , Special Session on Mathematical Biology, 2013 AMS Fall Eastern Sectional Meeting, Temple University

Slides for "Distance-Based Phylogenetic Methods Near a Polytomy" 10/10/13 at Clemson University

My poster "Distance-Based Phylogenetic Methods Around a Polytomy" for SIAM AG13 at Colorado State University. Here is an ealier version for Evolution 2013 in Snowbird, Utah.

Slides for "Distance-Based Phylogenetic Inference" 3/21/13 at Winthrop University

Slides for "Using EL-Shellability to Characterize Finite Semimodular and Geometric Lattices" 10/14/12 at Tulane University

My poster Polyhedral Combinatorics of UPGMA Cones from the SIAM Annual Meeting/AWM Workshop July 9-13 2012. Here is an earlier version from SIAM/AG11 at NCSU in October 2011 and another version from Algebraic Statistics in the Alleghenies at Penn State, June 2012.

Slides for "The Geometry of Tree Reconstruction" from the NCSU Graduate Algebra Seminar 9/30/11

Slides for "A lexicographic shellability characterization of geometric lattices." Algebra Seminar at UNC-Charlotte 11/30/11


Upcoming/Ongoing Activities

2014 Joint Meetings in Baltimore, MD

Triangle Lectures in Combinatorics Now with funding for participants!!!! Check it out!!!!



I co-organize the Graduate Algebra Seminar with Emily Barnard. We meet most Wednesdays 3 pm in SAS Hall Room 1220. Our seminars are a combination of student talks and a journal club . Please contact one of us if you would like to speak or if you have a paper you would like to discuss in the journal club. We welcome speakers and paper suggestions for any algebra-related area (combinatorics, algebraic geometry, symbolic computation, lie algebras, algebraic topology.... ). Check the history from 2008 to today to see what sort of things people have talked about!


Past Courses

Math 114, Spring 2013: Introduction to Finite Mathematics with Applications

Math 114, Fall 2012

Math 108, Spring 2012: Precalculus II.


Some Past Activities

AMS Special Session on Mathematical Biology at Temple University, October 12-13, 2013

SIAM AG13 (Applied Algebraic Geometry), Fort Collins, CO, August 1-4, 2013

Evolution 2013 in Snowbird, Utah, June 21-26, 2013

IAS 2013 Program for Women and Mathematics, Princeton, NJ, May 13-24, 2013

Southeastern Sectional Meeting of the AMS in Oxford, MS, March 1-3 2013

Symposium and Workshop on New Methods for Phylogenetics and Metagenomics, February 16-17 2013

Special Session on Algebraic and Topological Combinatorics AMS Southeastern Sectional October 13-14 2012

AWM Poster Session/SIAM Annual Meeting July 9-13 2012

Algebraic Statistics in the Alleghenies June 9-15 2012

SIAM AG11 Conference on Applied Algebraic Geometry, October 6-9 2011

Commutative Algebra Summer School at MSRI June 6-17 2011



I received my B.S. in Mathematics at the University of Washington, Seattle, where I wrote an undergraduate thesis. My undergraduate advisor was Sara Billey.

NCSU AWM Chapter

NCSU Algebra and Combinatorics Seminar

NCSU Symbolic Computation and Tensor Seminar

NCSU Phylogenetics and Evolutionary Biology Seminar

Graduate Algebra Seminar