MATH 111B (Winter Quarter 2019).
Mathematical Modelling II

Instructor: David A. MEYER
Email: dmeyer "at" math "dot" ucsd "dot" edu
Office hours (Winter Quarter): AP&M 7256 F 12:00pm- 1:00pm, or by appointment
Lectures: Center Hall 217B MWF 11:00am-11:50am

TA: Linbo LIU
Email: linbo "at" ucsd "dot" edu
Office hours (Winter Quarter): AP&M 6414 M 7:00pm-8:00pm, or by appointment
Recitations: AP&M 2301 M 8:00pm-8:50pm

Course description

This is a second course in mathematical modelling. In 2019 I plan to focus on mathematical models drawn from a range of topics coordinated with students' projects, which are often outside the more familiarly mathematical sciences. (For inspiration see [1,2].) I may also, however, discuss some models of weather and of climate change. The relevant mathematical methods will include: (systems of) ordinary differential equations, graphs/networks, probability, partial differential equations, eigenvalues/eigenvectors, permutations, and dimension theory.

The goals of this course are: (1) to explain what it means to construct a mathematical model of some real-world phenomenon, (2) to introduce some of the mathematical ideas that are used in many such models, (3) to apply these methods to analyze one or more real problems, and (4) to understand how new mathematical ideas are motivated by such modelling.

The prerequisites are the lower-division math sequence through differential equations (20D) and linear algebra (18 or 31A), and a first course in mathematical modeling (111A), or consent of the instructor. Please contact me if you are interested but unsure if your mathematics background will suffice.

The textbook is E. A. Bender, An Introduction to Mathematical Modeling (Mineola, NY: Dover 2000).

I expect interest and enthusiasm from the students in this class. 30% of the grade is class participation, which includes occasional homework assignments, often for class discussion. 70% of the grade is based upon a mathematical modelling project for which each student writes a proposal (15%), writes a preliminary report (10%), gives a final presentation (20%), and writes a final report (25%). Some titles of projects from previous years are listed below.

I recommend, but do not require, that you prepare your written materials using some dialect of TeX [3]. In any case, please do not send me Word documents; convert them to pdf first.

Related events

Mar 11, 2019 Application deadline for UCSD Physical Sciences Undergraduate Summer Research Award
Feb 1, 2019 Application deadline for Perimeter Scholars International Masters Program
Jan 31, 2019 Application deadline for Mathematical and Theoretical Biology Institute Summer Program
Jan 7, 2019 Application deadline for Perimeter Institute's Undergraduate Theoretical Physics Summer Program

Syllabus (homework in green)

Jan 7, 2019
DM lecture
administrative details
overview/motivation
         models, metaphors & imagination [slides]
discussion of project ideas
         E. Agliari et al., "Efficiency of information spreading in a population of diffusing agents",
         Physical Review E 73 (2006) 046138
         A. Apolloni et al., "A study of information diffusion over a realistic social network model",
         in Proceedings of IEEE International Conference on Computational Science and Engineering (2009).
         F. Baker, The Basics of Item Response Theory
         (College Park, MD: ERIC Clearinghouse on Assessment and Evaluation 2001).
HWK (for W Jan 9).
         (Re)read Bender, Chap. 1. What is modeling?; Varian [4]; Gray [5]; Goldin [6]

Jan 9, 2019
DM lecture
discussion of project ideas
         X. Diego et al., "Key features of Turing systems are determined purely by network topology",
         Physical Review X 8 (2018) 021071
         T. O'Donoghue and J. Somerville, "Modeling risk aversion in economics",
         Journal of Economic Perspectives 32 (2018) 91-114.
         J. Peck et al., "Lower bounds to the robustness to adversarial perturbations",
         in Proceedings of Advances in Neural Information Processing Systems 30 (2017).
         F. Angelini and M. Castellani, "Culture and economic value: A critical review",
         Journal of Cultural Economics (2 November 2018) 1-16.
Jan 11, 2019
DM lecture
discussion of project ideas
         R. F. Engle et al., "A dymimic model of housing price determination",
         Journal of Econometrics 28 (1985) 307-326.
HWK (for F Jan 18).
         Draft project proposal:
                 Describe the system for which you propose to construct a mathematical model.
                 What question will the model answer? Why is that important/interesting?
                 Has anything relevant been done to model this system previously? Give references.
                 What features/variables will the model include?
                 What features/variables may be relevant but will be exogenous to your model?
                 What kind of mathematics will you use?
                 If you intend to use real data, describe them and explain how you will get them.
                 Give an approximate timeline for accomplishing the various pieces of your project.
         Should be 2-4 pages. Please submit a pdf file electronically, ideally from a TeX [3] document.
Jan 14, 2019
DM lecture
stochastic models
         states of a system
         why make transitions between states probabilistic
         the Markov property
         Example: tic-tac-toe against an opponent who plays randomly
         Example: random walk
         transition matrix and probability distribution vector over states
         Example: multiple random walkers with a dynamical network of relations
Jan 16, 2019
DM lecture
graduate admissions data
         basic ideas of data analysis:
                 compile data; anonymize data; clean data
                 explore data
                 construct a model; fit the model
         ratings have large variance
Jan 18, 2019
DM lecture
         more basic ideas of data analysis:
                 try to improve model, possibly by changing completely
                 fit the new model
                 iterate
         total and partial orders
         low rank approximation
         alternating minimization
Jan 21, 2019
No lecture; Martin Luther King, Jr. day.
California "King" tide: 8:35am
Jan 23, 2019
DM lecture
         another basic idea of data analysis: overfitting
                 fitting a degree n-1 polynomial through n points
                 Newton's method
                 Lagrange's theorem
                 [code]
Jan 25, 2019
DM lecture
         an additive model, with the same number of parameters
         testing for overfitting with cross-validation
         semi-order as output of model
Jan 28, 2019
project discussions
         John Lam: insurance and reinsurance markets
                 point processes and marked point processes
         Nick Roberts: adversarial examples for neural networks
                 multivariable Taylor series error bounds
         Marina Torras: Fibonacci spirals
                 symmetry breaking in PDEs
Jan 30, 2019
project discussions
         Samantha Ngan: optimizing game play
                 dynamical network models
         Terry Le: evaluating student preparation
                 item response theory models
         Andrew Chavez: valuing public art
                 quantifying cultural value
Feb 1, 2019
project discussions
         Jessica Lee: predicting house prices
                 data collection and feature selection
         Xiangyu Liu: optimizing quadcopter design
                 aerodynamics
         Brian Nguyen: predicting Amazon pricing
                 supply and demand
Feb 4, 2019
DM lecture
Climate change: global warming and sea level rise
         What would happend to sea level if Greenland's ice sheet melted? (Part 1) [slides]
Feb 11, 2019
No lecture; DM at the Southwest Quantum Information and Computation Workshop.
Feb 13, 2019
project progress reports
Feb 25, 2019
DM lecture
HWK (for weeks 9 & 10).
         20+5 minute presentation
                 describe system & state question [~4 minutes]
                 describe model, but don't go into too many details [~8 minutes]
                 explain results & answer to question [~7 minutes]
                 how could model be improved/extended? [~1 minute]
         I recommend a slide presentation for efficiency.

Feb 27, 2019
DM lecture
HWK (due Friday, Mar 15).
         Final project report
                 Introduction: describe system & explain question and why it is interesting
                 Describe model: what is being included/excluded; how do different pieces fit together; derive model/eqiuations
                 [somewhere in the Introduction or Description, explain previous relevant models & why yours is different]
                 Describe data: what are they? from where do they come? how reliable are they?
                 Analyze model: explain math/computations; give results
                 Conclusion: what is the answer to the question, from results? discuss answer; How might model be extended/improved?
                 References: standard bibliographical format; citations in text; not wikipedia
         Approximately 10 pages; pdf, not Word..
         You can include data/code as separate files, or links.
         Not a diary ("First I did this, then this, ..."); it should read like a scientific paper.
         Write sentences, paragraphs, sections, in the best English you know; not bullet points like on a slide presentation.

Suggested reading

[1] I. Asimov, The Foundation Trilogy (New York: Gnome Press 1951).
[2] P. R. Krugman, "Introduction to The Foundation Trilogy" (Folio Society 2012).
[3] D. E. Knuth, The TeXbook, Computers and Typesetting, Volume A (Reading, Massachusetts: Addison-Wesley 1984).
[4] H. R. Varian, "How to build an economic model in your spare time", The American Economist 41 (1997) 3—10.
[5] N. Gray, "Abstract science", The Huffington Post (2012).
[6] A. Bleicher interview with R. Goldin, "Why math is the best way to make sense of the world", Quanta magazine (2017).

Titles of projects from previous years


Last modified: 8 March 2019.