Difference between revisions of "SIAM Student Chapter Seminar/Fall2019"

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(Undo revision 19859 by Xshen (talk))
 
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__NOTOC__
 
__NOTOC__
  
*'''When:''' Every other Friday at 1:30 pm
+
*'''When:''' Most Friday at 11:30am
*'''Where:''' B333 Van Vleck Hall
+
*'''Where:''' 901 Van Vleck Hall
 
*'''Organizers:''' [http://www.math.wisc.edu/~xshen/ Xiao Shen]
 
*'''Organizers:''' [http://www.math.wisc.edu/~xshen/ Xiao Shen]
 
*'''Faculty advisers:''' [http://www.math.wisc.edu/~jeanluc/ Jean-Luc Thiffeault], [http://pages.cs.wisc.edu/~swright/ Steve Wright]  
 
*'''Faculty advisers:''' [http://www.math.wisc.edu/~jeanluc/ Jean-Luc Thiffeault], [http://pages.cs.wisc.edu/~swright/ Steve Wright]  
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<br>
 
<br>
  
== Spring 2020 ==
+
== Fall 2019 ==
  
 
{| cellpadding="8"
 
{| cellpadding="8"
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!align="left" | title
 
!align="left" | title
 
|-
 
|-
|Jan 31
+
|Sept. 27, Oct. 4
|[https://lorenzonajt.github.io/ Lorenzo Najt] (Math)
+
|[http://www.math.wisc.edu/~xshen/ Xiao Shen] (Math)
|''[[#Jan 31, Lorenzo Najt (Math)|Ensemble methods for measuring gerrymandering: Algorithmic problems and inferential challenges]]''
+
|''[[#Sep 27, Oct 4: Xiao Shen (Math)|The corner growth model]]''
 
|-
 
|-
 
|-
 
|-
|Feb 14
+
|Oct. 18
|[https://www.math.wisc.edu/~pollyyu/ Polly Yu] (Math)
+
|[https://scholar.google.com/citations?user=7cVl9IkAAAAJ&hl=en Bhumesh Kumar] (EE)
|''[[#Feb 14, Polly Yu (Math)|Algebra, Dynamics, and Chemistry with Delay Differential Equations]]''
+
|''[[#Oct 18: Bhumesh Kumar (EE)|Non-stationary Stochastic Approximation]]''
 +
|
 
|-
 
|-
 
|-
 
|-
|Feb 21
+
|Oct. 25
|Gage Bonner (Physics)
+
|Max (Math)
|''[[#Feb 21, Gage Bonner (Physics)|Growth of history-dependent random sequences]]''
+
|''[[#Oct 25: Max (Math)|Coalescent with Recombination]]''
 +
|
 +
|-
 +
|-
 +
|Nov. 8
 +
|Hongfei Chen (Math)
 +
|''[[#Nov 15: Hongfei Chen (Math)| Brownian swimmers in a channel]]''
 +
|
 +
|-
 +
|-
 +
|Dec. 10
 +
|[http://www.maths.manchester.ac.uk/~higham/ Nicholas J. Higham] (University of Manchester)
 +
|''[[#Dec 10: Nicholas J. Higham  (University of Manchester)|Scientific Writing]]''
 
|-
 
|-
 
|-
 
|-
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== Abstracts ==
 
== Abstracts ==
  
=== Jan 31, Lorenzo Najt (Math) ===
+
=== Sep 27, Oct 4: Xiao Shen (Math) ===
'''Ensemble methods for measuring gerrymandering: Algorithmic problems and inferential challenges'''
+
'''The corner growth model'''
 +
 
 +
Imagine there is an arbitrary amount of donuts attached to the integer points of Z^2. The goal is to pick an optimal up-right path which allows you to eat as much donuts as possible along the way. We will look at some basic combinatorial observations, and how specific probability distribution would help us to study this model.
 +
 
 +
=== Oct 18: Bhumesh Kumar (EE) ===
 +
'''Non-stationary Stochastic Approximation'''
 +
 
 +
Abstract: Robbins–Monro pioneered a general framework for stochastic approximation to find roots of a function with just noisy evaluations.With applications in optimization, signal processing and control theory there is resurged interest in time-varying aka non-stationary functions. This works addresses that premise by providing explicit, all time, non-asymptotic tracking error bounds via Alekseev's nonlinear variations of constant formula.
 +
 
 +
Reference: https://arxiv.org/abs/1802.07759 (To appear in Mathematics of Control, Signals and Systems)
 +
 
 +
=== Oct 25: Max (Math) ===
 +
'''Coalescent with Recombination'''
 +
 
 +
I will talk about the continuous time coalescent with mutation and recombination, with a focus on introducing key concepts related to genetic distance and evolutionary relatedness. The talk will be informal and accessible.
 +
 
 +
=== Nov 15: Hongfei Chen (Math) ===
 +
'''Brownian swimmers in a channel'''
 +
 
 +
Abstract: Shape matters! I will talk about how their shapes affect their mean reversal time.
 +
 
 +
=== Dec 10: Nicholas J. Higham (University of Manchester) ===
 +
'''Scientific Writing'''
 +
 
 +
I will discuss various aspects of scientific writing, including
  
We will review some recent work regarding measuring gerrymandering by sampling from the space of maps, including two methods used in a recent amicus brief to the supreme court. This discussion will highlight some of the computational challenges of this approach, including some complexity-theory lower bounds and bottlenecks in Markov chains. We will examine the robustness of these statistical methods through their connection to phase transitions in the self-avoiding walk model, as well as their dependence on artifacts of discretization. This talk is largely based on https://arxiv.org/abs/1908.08881
+
the craft of writing in general,
  
=== Feb 14, Polly Yu (Math) ===
+
• aspects specific to mathematical writing,
'''Algebra, Dynamics, and Chemistry with Delay Differential Equations'''
 
  
Delay differential equations (DDEs) can exhibit more complicated behavior than their ODE counterparts. What is stable in the ODE setting could exhibit oscillation in DDE. Where do delay equations show up anyway? In this talk, we’ll introduce DDEs, and how (sort-of-)linear algebra gives information about the stability of DDEs.
+
• English Usage,
  
 +
• workflow, and
  
=== Feb 21, Gage Bonner (Physics) ===
+
• revising drafts and proofreading.
''' Growth of history-dependent random sequences'''
 
  
Unlike discrete Markov chains, history-dependent random sequences are sequences of random variables whose "next" term depends on all others seen previously. For this reason, they can be difficult to analyze. I will discuss some simple and fun cases where the long-term behavior of the sequence can be computed explicitly in expectation.
+
Plenty of examples and links to further information will be given. I will also discuss
 +
my experiences in preparing ''Handbook of Writing for the Mathematical Sciences'' (third
 +
edition, SIAM, 2020).
  
  
 
<br>
 
<br>

Latest revision as of 00:11, 18 September 2020


  • When: Most Friday at 11:30am
  • Where: 901 Van Vleck Hall
  • Organizers: Xiao Shen
  • Faculty advisers: Jean-Luc Thiffeault, Steve Wright
  • To join the SIAM Chapter mailing list: email [join-siam-chapter@lists.wisc.edu].


Fall 2019

date speaker title
Sept. 27, Oct. 4 Xiao Shen (Math) The corner growth model
Oct. 18 Bhumesh Kumar (EE) Non-stationary Stochastic Approximation
Oct. 25 Max (Math) Coalescent with Recombination
Nov. 8 Hongfei Chen (Math) Brownian swimmers in a channel
Dec. 10 Nicholas J. Higham (University of Manchester) Scientific Writing

Abstracts

Sep 27, Oct 4: Xiao Shen (Math)

The corner growth model

Imagine there is an arbitrary amount of donuts attached to the integer points of Z^2. The goal is to pick an optimal up-right path which allows you to eat as much donuts as possible along the way. We will look at some basic combinatorial observations, and how specific probability distribution would help us to study this model.

Oct 18: Bhumesh Kumar (EE)

Non-stationary Stochastic Approximation

Abstract: Robbins–Monro pioneered a general framework for stochastic approximation to find roots of a function with just noisy evaluations.With applications in optimization, signal processing and control theory there is resurged interest in time-varying aka non-stationary functions. This works addresses that premise by providing explicit, all time, non-asymptotic tracking error bounds via Alekseev's nonlinear variations of constant formula.

Reference: https://arxiv.org/abs/1802.07759 (To appear in Mathematics of Control, Signals and Systems)

Oct 25: Max (Math)

Coalescent with Recombination

I will talk about the continuous time coalescent with mutation and recombination, with a focus on introducing key concepts related to genetic distance and evolutionary relatedness. The talk will be informal and accessible.

Nov 15: Hongfei Chen (Math)

Brownian swimmers in a channel

Abstract: Shape matters! I will talk about how their shapes affect their mean reversal time.

Dec 10: Nicholas J. Higham (University of Manchester)

Scientific Writing

I will discuss various aspects of scientific writing, including

• the craft of writing in general,

• aspects specific to mathematical writing,

• English Usage,

• workflow, and

• revising drafts and proofreading.

Plenty of examples and links to further information will be given. I will also discuss my experiences in preparing Handbook of Writing for the Mathematical Sciences (third edition, SIAM, 2020).