# Student Projects

## Determining College Success Based on High School Performance: Fitting Linear Mixed Models

**Students:** Brittany Strausser ‘18

**Faculty Mentor:** Dr. Brenna Curley

One of the challenges that college Admissions Offices face revolves around ensuring that retention rates rise or at least remain the same. In this Honors project, we attempt to predict student success at Moravian College. We use linear mixed effects models to describe the effects of high school Grade Point Average (GPA), SAT scores, and gender on college GPA; we additionally account for potential differences between high schools.

## Edge and Vertex Failure Games on Graphs

**Students:** Devon Vukovich ‘17

**Faculty Mentor:** Dr. Nathan Shank

This Honors project looked at problems that arise from the synthesis of Game Theory and Graph Theory. We analyzed a partizan combinatorial game where one player moves by deleting a single vertex and the other player moves by deleting a single edge from a graph. We then establish variants of this game by altering the sets of graphs that are unplayable for each player. We were able to solve this game and its variants on several graph classes including paths, wheels, and complete graphs.

## Partizan Graph Connectivity Games

**Students:** Devon Vukovich ‘17

**Faculty Mentor:** Dr. Nathan Shank

For this Summer SOAR Project, Devon worked as an undergraduate researcher for a REU hosted by Muhlenberg College. The REU was focused on working with the Online Encyclopedia of Integer Sequences (OEIS). He worked as part of a Graph Theory research team that examined sequences that arose from the Edge Distinguishing Chromatic Number of different graph classes. He also worked as part of a Game Theory research team that expanded upon research done in component deletion games played on graphs.

## Explorations of Game Theory and Properties of Factor Pair Latin Squares

**Students:** Makkah Davis ‘17

**Faculty Mentor:** Dr. Nathan Shank

This Summer SOAR research project was conducted at the 2017 Muhlenberg College Mathematics and Computer Science Summer Research Experience for Undergraduates Program (REU). Makkah worked on two unrelated research projects, one exploring properties of Factor Pair Latin Squares and one exploring Game Theory. The game theory project, in which we created a partisan variant of the popular combinatorial game, Nim, is played on a colored cycle graph. The bulk of our research was devoted to analyzing and solving our game.

## Subtractions Games

**Students:** Bryan Harvey ‘19

**Faculty Mentor:** Dr. Michael Fraboni

This semester SOAR project investigated questions in Combinatorial Game Theory. In particular, we determined the value of game positions for a family of subtraction games based on Beatty sequences.

## Clever Problem Solving II

**Students:** Edward Harbison ‘19

**Faculty Mentor:** Dr. Nathan Shank

This project develops additional problem solving skills by developing a series of 14 lessons based on topics seen in mathematical problem solving. We learn creative ways to approach interesting mathematical problems. Topics include: Generating Functions, Recurrence Relations, Probability Problems, Weird Calculus, Diophantine Equations, Games, Combinatorics, Hyperoperations, Permutations, and Divisibility Tricks

## Probability Theory

**Students:** Josie Novak ‘18

**Faculty Mentor:** Dr. Nathan Shank

This project was centered around learning the fundamentals of Probability Theory which is at the intersection of probability and analysis. Topics covered included Random Variables, Weak and Strong Law of Large Numbers, Properties of Convergence, Generating Functions, Markov Chains, and Random Walks.

## Squares of Graphs

**Students:** Emily Bolger ‘20, Rey Anaya ‘21, Peter Gingrich ‘21, Tatianna Machado ‘22

**Faculty Mentor:** Dr. Nathan Shank

In this project, we are exploring a topic of graph theory that focuses on the square of a directed graph. A standing conjecture states that for every oriented graph there is a vertex whose out-degree at least doubles in the square of the graph. We explore the different qualities of a square graph, while we work our way towards providing evidence the conjecture is indeed true.

## Reducing Cardinality Redundancy In P(n,2) Peterson Graphs

**Students:** Emily Reiter ‘19, Domingo Rodriguez ‘20, Morgan Reiner ‘19, Wyatt Patton ‘19, Bryan Harvey ‘19

**Faculty Mentor:** Dr. Nathan Shank

The dominating number of a graph is the minimum number of vertices needed so that every vertex in the graph is either in the dominating set or is adjacent to a vertex in the dominating set. In many graphs this means that there are vertices which are dominated more than once and/or the total number of vertices adjacent to the dominating set is very large, meaning some vertices may be highly over-dominated. In this project we try to find the ways to efficiently dominate Peterson graphs. If they can not be efficiently dominated, we try to find the dominating set which is the closest to efficient (Cardinality Redundancy).

## Data and Soul: Introductory Data Mining and Data Analysis on Music Data

**Students:** John Vonelli ‘18

**Faculty Mentor:** Dr. Thyago Mota, Dr. Brenna Curley

In this work, presented at the 2018 National Conference on Undergraduate Research (NCUR), we investigate how songs lyrically and musically influence popularity and emotional responses throughout contemporary history. We build a dataset of 27,346 songs that are listed on the Billboard “Hot 100” list from 1958 to 2017. We then use Spotify’s song metrics, together with a weighted sampling function, to evaluate how music changed over time.

## Games on Graphs

**Students:** Charles Peeke ‘19, Fred Younes ‘22, Mark Morykan ‘22, Erika Zarate ‘22

**Faculty Mentor:** Dr. Nathan Shank

For this project, we are focussing on edge deletion games on path graphs. With three players, each player takes a turn by removing an edge from a graph. The player that is forced to delete an edge and leaves a vertex isolated will lose the game. If you don’t see a way to win the game for yourself, you try your best to make sure that you don’t lose.

## Exploration of Potential Energy Functions of the 4 3𝝥0 Electronic State of NaC

**Students:** Rachel Myers ‘18

**Faculty Mentor:** Dr. Shannon Talbott, Dr. Ruth Malenda

In Physics, one area of research is determining the electronic potential energy curves of diatomic molecules. In this Honors project focused on the diatomic molecule sodium-cesium (NaCs), namely the 4 3𝝥0 electronic state of NaCs, which has a complicated potential structure with a double well. Using experimental data from collaborators, functional forms of the double well energy functions were explored using two approaches. Initially, the double well electronic state was considered as a combination of simple, standard single well forms with a switching term to transition between single wells. Then, a Spline Exponential-Morse Long Range potential function was found using a program called betaFIT.

## An Exploration of Lie Algebras and Kostant’s Weight Multiplicity Formula

**Students:**Brett Harder ‘16

**Faculty Mentor:** Dr. Shannon Talbott

Lie algebras are particular vector spaces with applications to physics like representing symmetries in atoms such as hydrogen as well as applications to special and general relativity. Just as eigenvectors and eigenspaces can be used to decompose a vector space into subspaces, weights and weight spaces can be used to decompose a Lie algebra into subalgebras, in certain cases. This decomposition can help us to understand these particular Lie algebras. Kostant’s multiplicity formula is concerned with weights, and while it appears to be simplistic, calculations are often extremely difficult. The aim of this Honors project was to add to the understanding of the multiplicity formula.

## Quasi-Crowns

**Students:**Alexis Thiel ‘16

**Faculty Mentor:** Dr. Shannon Talbott

In graph theory, one problem that has motivated research for well over a century is the graph coloring problem. That is, what is the minimum number of colors required to color the vertices of a graph so that no adjacent vertices are the same color? This problem is an NP-complete problem, but there are particular families of graphs where this question has be answered. One such family of graphs comes from a particular type of partially ordered set called a crown. This SOAR project explored the notion of layering such crowns.

## Magic Square of Squares

**Students:**Ed Harbison ‘19, Matthew Meyers ‘22, Emily Miller ‘22, Kimberly Wolf ‘22

**Faculty Mentor:** Dr. Nathan Shank

Our project focuses on magic squares. These are grids, usually a 3×3, filled in with integers such that each row, column, and diagonal adds up to the same number. However, no one has found a 3×3 magic square where each element is a perfect square, which is where an integer’s square root is also an integer. We are set out to find a solution, if it exists.