## Wednesday, September 28, 2016

### Dan Velleman, Amherst College

*What to expect in a game of memory*

Abstract: The game of memory is played with a deck of 2n cards. The cards are numbered from 1 to n, with each number appearing twice. The deck is shuffled and then the cards are laid out face down. A move consists of flipping first one card and then another. If the cards match, then both are removed from play. If not, they are flipped back over. Play ends when all pairs have been removed. In this talk, I will discuss the average number of moves required to complete a game of memory.

6:00 pm in Seeley Mudd 206. There will be pizza at this talk but you MUST RSVP by Monday, September 26 to awtorrey@amherst.edu\

## Thursday, October 6, 2016

### David Cox, Amherst College

*Graphs, Sudoku, and Equations*

Abstract: On the surface, polynomial equations look like a part of algebra, which is very different from graph theory, where the basic objects consist of vertices linked by edges. And both of these seem totally removed from the Sudoku puzzles that appear in newspapers and on the web. In my lecture, I will explain that if you color the vertices of a graph so that vertices linked by an edge have different colors, then you get a system of polynomials that can shed light on the original coloring problem. I will also show how to recast a Sudoku puzzle as a graph coloring problem, which will enable us to use the computational theory of polynomial equations to solve Sudoku puzzles.

4:30 pm in Seeley Mudd 206 with refreshments in Seeley Mudd 208 at 4:00 pm

## Wednesday, October 12, 2016

### Bill Dunham

### Bryn Mawr

#### An Afternoon with Euler

Abstract: Among history’s greatest mathematicians is Leonhard Euler (1707-1783), the Swiss genius who produced an astonishing 25,000 pages of pure and applied mathematics of the highest quality.

In this talk, we sketch Euler’s life and review a few of his contributions to number theory, algebra, geometry, and other branches of mathematics. Then we examine a particular proof, his derivation of the so-called “Euler Identity” (e^{ix} = cos x + i sin x) via integral calculus.

Condorcet, in his Eulogy to Euler, observed that “All mathematicians now alive are his disciples.” I hope to show that these words are as true today as when first penned over two centuries ago.

NOTE: This talk should be accessible to anyone with a calculus background.

Seeley Mudd 206 at 4:30 pm with refreshments in Seeley Mudd 208 at 4

## Friday, October 28, 2016

### Valeria Espinosa

#### Did the Military Interventions in the Mexican Drug War Increase Violence?

We analyze publicly available data to estimate the causal effect of military interventions on the homicide rates in certain problematic regions in Mexico. We use the Rubin Causal Model (Rubin 1974) to compare the post intervention homicide rate in each intervened region to the hypothetical homicide rate for that same year had the military intervention not taken place. Because the effect of a military intervention is not confinced to the municipality subject to the intervention, a non-standard definition of units is necessary to measure plausibly the causal effect of the intervention under the standard no-interference assumptions of SUTVA. Donor pools for each missing potential outcome under no intervention are created, thereby allowing for the estimation of unit level causal effects. A multiple imputation approach accounts for the uncertainty about the missing potential outcomes.

12:00 pm in Seeley Mudd 206 A light lunch will be provided

## Friday, October 28, 2016

### Family Weekend Reception

Seeley Mudd 206 3:30 - 4:30 pm

## Harris Daniels named honorary member of Class of 2016

Congratulations to Mathematics Professor Harris Daniels who was named an honorary member of the Amherst College Class of 2016. Harris received a certificate and a cane (the same that the graduating seniors receive).

## Mu Sigma Rho award plus new group of inductees

Ningyue (Christina) Wang '16 has been chosen as the recipient of the 2016 Boston Chapter of the American Statistical Association Mu Sigma Rho Award. This annual award recognizes one outstanding statistics undergraduate per year in the BCASA region (Rhode Island, Massachusetts, Maine, New Hampshire, and Vermont). Mu Sigma Rho is the national statistics honor society. Christina was selected as the inaugural winner of the award based on her outstanding achievements in statistics (she had been inducted into Mu Sigma Rho in 2015).

In addition to Christina's award, eleven Amherst College students were inducted into Mu Sigma Rho. Congratulations to Jonathan Che, Stephany Flores-Ramos, Paul Gramieri, Connor Haley, Azka Javaid, Rishi Kowalski, Levi Lee, Amanda Rosenbaum, Muling Si, Sarah Teichman, and Alex Titelbaum for their academic achievements and distinction.

**Amherst Students win Best in Show and Best in Group at Five College ASA DataFest **

Congratulations to Jonathan Che, Pei Gong, Timothy Lee, Shelly Tang, and Sarah Teichman for being named "Best in Group" and "Best in Show" at the Five College ASA DataFest. Other winners from Amherst included the team consisting of Jordan Browning, Jerry Chen, Brendan Seto, Leonard Yoon, and Jingwen Zhang. DataFest is a data analysis competition where teams of up to five students have a weekend to attack a large, complex, and surprise dataset. More than 130 undergraduate students from the Five Colleges participated in this year's event. More details can be found at http://www.science.smith.edu/datafest/2016/04/04/recap-of-winners-from-datafest-2016/

### Mathematics Professor Michael Ching named Lazerowitz Lecturer (April 14, 2016)

Congratulations to Michael Ching, who has been named as the 2015-2016 Lazerowitz Lecturer. His talk, entitled "Shape" took place on Thursday, April 14th in Paino Lecture Hall (Beneski). The abstract states that the universe around us is full of fascinating shapes: we see them in the natural world, we put them in our buildings, we see them in the remnants of exploded stars. Einstein proposed that the universe itself has an interesting shape - that space is curved. In the world of our imagination, there are even more fantastic shapes that have beautiful and interesting properties: worlds that you can walk all the way around and come back as a mirror image of yourself, surfaces that can be knotted like higher-dimensional pieces of string.

In this talk he will describe how mathematicians think of shapes and understand their fundamental properties. How can we tell two shapes apart? What ways can two different shapes be similar? How can we “measure” shape? Can we hope to build a catalog of all possible shapes?

This ethereal topic has recently started to have more down-to-earth applications. The emergence of “big data” has led to a need for new ways to analyze that data, and one such analysis is to look for interesting shapes therein. Where before we might be happy to find that a set of data forms a straight line, now there are ways to detect circles, surfaces and higher-dimensional shapes hidden in the numbers. These higher-order patterns can illuminate unexpected relationships and tell you something that traditional data analysis might miss.

### Dedication of the George D. Olds Reading Room

During the summer of 2015, the 5th floor of Seeley Mudd was renovated with new faculty offices and study space. We are having a reception (with non-Val food!) to celebrate this, as well as the unveiling of a plaque dedicating the room to George Olds (professor of math and President of the College in the 1920s).

### Cox, Little, and O'Shea to Receive 2016 AMS Steele Prize for Exposition

The AMS Leroy P. Steele Prize for Exposition was awarded to three mathematicians: **David Cox** (Amherst College), **John Little** (College of the Holy Cross), and **Donal O'Shea** (New College of Florida) "for their book *Ideals, Varieties, and Algorithms*, which has made algebraic geometry and computational commutative algebra accessible not just to mathematicians but to students and researchers in many fields."

Algebraic geometry has a reputation for being impenetrably technical and abstract. By requiring only linear algebra as a prerequisite, the book by Cox, Little, and O'Shea invites a broad audience of readers into this central branch of mathematics. Using geometry to introduce core topics and appealing to computational theory to prove fundamental results, they complement the development of theoretical results with applications to such topics as automated theorem proving and robotics. All of this is delivered with crystal-clear exposition and top-quality writing.

"Even more impressive than [the book's] clarity of exposition is the impact it has had on mathematics," the prize citation states. "*CLO*, as it is fondly known, has not only introduced many to algebraic geometry, it has actually broadened how the subject could be taught and who could use it." The book helped bring the topic of computational algebra into the mathematical mainstream. In particular, the book's presentation of the theory of Gröbner bases "has done more than any other book to popularize this topic." Gröbner bases provide a way to efficiently automate certain calculations in algebraic geometry. The subject of Gröbner bases has boomed in recent years, in part because of significant applications to such diverse problems as oil exploration, software design, genetics, and robot kinematics.

Originally published by Springer Verlag in 1992, the fourth edition of *CLO* appeared just this year. The book has truly become a classic. It not only has provided many of today's mathematicians with their first grounding in algebraic geometry, but also has brought this area of mathematics to the service of scientists and engineers. All three authors are top-flight mathematicians at small colleges; O'Shea was at Mount Holyoke College for more than 30 years before becoming the president of New College of Florida in 2012. Their book shows how small colleges make signal contributions to the advancement of mathematics, the training of future mathematicians, and the applications of mathematics to other disciplines. The AMS Steele Prize is one of the highest distinctions in mathematics.

Cox received the Lester R. Ford Prize from the Mathematical Association of America (2012) and was elected as a Fellow of AMS (2013). Little has received distinctions for his outstanding service to the College of the Holy Cross, including its Distinguished Teaching Award (2003) and the Anthony and Renee Marlon Professorship in the Sciences (2012-2015). In 2008, O'Shea received the Peano Prize for his book *The Poincaré Conjecture: In Search of the Shape of the Universe* (Walker & Company, 2006).

### Navajo Math Circles, A Film By: George Paul Csiccery

This documentary explores the challenges the Navajo Nation faces in increasing the quantitative literacy of its children, while highlighting the special connections between Navajo culture, natural beauty, and mathematics. math circles have proven a successful way to improve math education through lively collaborations between students and mathematicians. Please join us for a screening of the film and an information dicsussion over Pizza.

Presented by The Multicultural Resource Center and the Department of Mathematics and Statistics.

Thursday, March 24, 2016, 6:00 pm at the Multicultural Resource Center.

*For accessibility needs and/or accommodations please contact the Multicultural Resource Center at 413-542-5372.

### Math and Stats Alumni panel

This coming Saturday (November 14) in Seeley Mudd 206 we are pleased to welcome back six of our math major alumni to make presentations about their career paths and how math and stats have been useful to them in that. They will also give you advice on how to make the most of your time at Amherst.

We have the following presenters:

Anna Mullen '09: investment analyst

Benjamin Dickman '08: postdoctoral scholar in math education

Mary Beth Broadbent '10: marketing analyst

Caleb Hayes-Deats '06: assistant US attorney

Anna Haring '10: physical therapist

Jesse Carroll '07: actuarial analyst

They will each give a 10-15 minute presentation with time for questions. The event will start at 2pm with three presentations from 2-3pm, a break for refreshments and informal questions, then three more talks from 3-4pm.

### Statistical Analysis of Big Genetics and Genomics Data

#### CVC colloquium: Monday, November 16, 2015 4:30pm, SMUDD 206, refreshments 4pm in SMUDD 208

Xihong Lin, Department of Biostatistics, Harvard T.H. Chan School of Public Health

Abstract: The human genome project in conjunction with the rapid advance of high throughput technology has transformed the landscape of health science research. The genetic and genomic era provides an unprecedented promise of understanding genetic underpinnings of complex diseases or traits, studying gene-environment interactions, predicting disease risk, and improving prevention and intervention, and advancing precision medicine. A large number of genome-wide association studies conducted in the last ten years have identified over 1,000 common genetic variants that are associated with many complex diseases and traits. Massive targeted, whole exome and whole genome sequencing data as well as different types of -omics data have become rapidly available in the last few years. These massive genetic and genomic data present many exciting opportunities as well as challenges in data analysis and result interpretation. They also call for more interdisciplinary knowledge and research, e.g., in statistics, machine learning, data curation, molecular biology, genetic epidemiology and clinical science. In this talk, I will discuss analysis strategies for some of these challenges, including rare variant analysis of whole-genome sequencing association studies; analysis of multiple phenotypes (pleiotropy), and integrative analysis of different types of genetic and genomic data.

#### Ongoing - Math and Stats Table every Monday, noon - 1:30, Valentine Terrace Room B MOST weeks

Past News and Events can be found in the Archive.

### Causal Inference: Identifying Subgroups by their Response to Treatment

#### Statistics Colloquium: Thursday, October 22 7:30pm, SMUDD 206

Sarah Anoke, Department of Biostatistics, Harvard T.H. Chan School of Public Health

Abstract: Causal inference is a field of statistics focused on measuring a particular type of relationship between two variables. Referring to these two variables as the `treatment’ and the `outcome’, we consider the value that an individual’s outcome would take if the treatment was present, and the value that the individual’s outcome would take if the treatment was absent. The difference in these two potential outcomes is the treatment effect. Every individual has their own individual treatment effect (ITE). But because only one of these two potential outcomes is observable, ITEs cannot be estimated from observed data. To overcome this problem, the average outcome among a group of individuals unexposed to treatment is subtracted from the average outcome among a group of individuals exposed to treatment, yielding an average treatment effect (ATE). It is of interest to identify subgroups for which the subgroup-specific ATE is very different from the overall ATE. Knowing the overall ATE is arguably misleading; we would prefer to know that the drug has no effect within women but a dramatic effect within men. How then, can the data tell us which subgroups respond particularly well or poorly to treatment, without advance knowledge of these subgroups?

### Statistical Tools and Challenges for Monitoring Migratory Birds

#### Statistics Colloquium: Friday, October 30th 2:00pmpm, Amherst College Frost Library 211

Emily Silverman, Statistician, Division of Migratory Bird Management, U.S. Fish & Wildlife Service

Abstract: Federal management of migratory birds began 100 years ago, when the United States signed the 1916 Convention for the Protection of Migratory Birds with Great Britain (for Canada). These protections were codified in the Migratory Bird Treaty Act (MBTA) of 1918, which now covers over 800 species of birds, and stands as one of the earliest U.S. environmental laws. The evolution of management approaches since the MBTA has led to the development of monitoring programs and quantitative methods in wildlife science. I will present the history of bird monitoring and statistical methods for population assessment and will discuss new approaches, challenges, and how a solid understanding of statistical concepts is essential for informed management. Drawing on examples from my own work, I will highlight the interdisciplinary skills needed to operate effectively as a scientist and statistician in a resource management agency. As our ability to collect information about the natural world expands in an increasingly digital world, the need for innovative, technically-adept wildlife scientists is expanding.

### First prize in Undergrad Statistics Class Project Competition

Congratulations to Johannes Ferstad and Thomas Savage (both '15) for winning first prize in the Undergraduate Statistics Project competition for their submission: *Large Differences in County-Level Mortality Rates Related to Race and Economic Advantage. *

### Mu Sigma Rho Induction

In 2012-2013, Amherst began nominating outstanding students in Statistics to membership in Mu Sigma Rho,the National Statistics Honorary Society. This year, the Department would like to congratulate Johannes Ferstad, Jason Premo, Thomas Savage, Jarvis Sill, and Ningyue (Christina) Wang on their nomination and induction into Mu Sigma Rho. Congratulations!

### DataFest Results

Amherst College was represented by 4 teams (a total of 18 students) at the Five College DataFest held the weekend of March 27-29, part of a national competition sponsored by the American Statistical Association. This was the second year for the event in the Five Colleges. Participants spent 25 hours over the course of the weekend tackling a large dataset, and gave 6-minute presentations summarizing their insights. 6 teams out of 16 total were awarded prizes. Amherst teams won awards for: Best Business Value (Team: Jo-Jo ToAlTrev), Best Pitch (Team: 95% Confident), and Best Use of External Data (Team: The Women in Black). We were thrilled by the turn-out and hard work from Amherst students, and look forward to participation next year. Congratulations to all participants!

- Best Pitch: 95% Confident (Amherst College): Paul Gramieri, Caleb Ki, Levi Lee, Thomas Matthew, and Albert Yu
- Best Business Value: Jo-Jo ToAlTrev (Amherst College): Johannes Ferstad, Jon Jordan, Thomas Savage, Trevor Smith, Alexander Titelbaum
- Best Use of External Data: Women in Black (Amherst College): Muling Si, Jenny Xiao, Qi Xie, Jingwen Zhang

### Mathematics, Statistics, and Basketball

Take a look at this NYT article about our women's basketball team, which includes quotes from Megan Robertson ('15), who is majoring in both mathematics and statistics.

### Amherst Student Articles About Recent Mathematics Graduates

#### Daniel Ang

http://amherststudent.amherst.edu/?q=article/2015/05/22/one-man-orchestra-composes-his-own-path

#### Dvij Bajpai

http://amherststudent.amherst.edu/?q=article/2015/05/22/curious-engineer-who-wears-many-hats

#### Megan Robertson

http://amherststudent.amherst.edu/?q=article/2015/05/22/rising-above-odds-and-court

#### Zalia Rojas

http://amherststudent.amherst.edu/?q=article/2015/05/22/building-bridges-through-math-and-spanish

View a calendar of events in the Five College area.