Tuesday, March 20, 2018

In Conclusion, Hilarity Ensues.

"Hilarity ensues." is acceptable for the Conclusions section of a paper, right?

What Happens in Provo Stays in Provo

I am at the airport — with a 165-minute delay (sigh...) in my flight — to visit the mathematics department at BYU. I am being hosted by Emily Evans, who is on their faculty and is also a friend of mine from college.

I will somehow deal with the fact that I am not allowed to have coffee on campus. :)

Sunday, March 18, 2018

Algorithms in the Form of IKEA Instructions

I think my life could not possibly have been complete without seeing algorithms presented in the form of IKEA instructions. I am highly amused. :)

(Tip of the cap to Lior Pachter.)

We Kid the Statisticians Because We Love Them


(Tip of the cap to Kerstin Nordstrom.)

Saturday, March 17, 2018

Some Really Old Boardgames

Take a look at this article about some really old boardgames (and one from 1940), including one from the 17th century, that are in a collection in the Houghton Library.

I like the cover of "The Magic Ring". :)

(Tip of the cap to Gabrielle Birkman.)

Society for Impure Mathematics (SIM)

I am an active member of SIAM, the Society for Industrial and Applied Mathematics.

Here's a Fun (Alternative) Fact: The Society for Industrial and Applied Mathematics used to be known as "Society for Impure Mathematics" (SIM), because those of us who do applied mathematics are less pure than other types of mathematicians, bless their hearts.

But perhaps this great organization really ought to change its name to "Society for Impure Mathematics", to appease the theoretical mathematicians who like to call themselves "pure" mathematicians.

As you may have gathered, I find the phrasing "pure mathematics" to be incredibly demeaning towards applied mathematics and applied mathematicians. (The term "unadulterated mathematics" is even worse, so I suppose that my subject of choice is "adulterated mathematics".) I really dislike being considered impure, by implication of the term in use. "Pure mathematics" should really be called "theoretical mathematics", just like in every other science.

Additionally, here are two of my tweets on this and related subjects.

Update: I corrected the acronym (I had written "SIP"), because apparently I am having a problem with English today.

Update: If we want to preserve the acronym SIAM and don't mind a bit of redundancy, it can stand for "Society for Impure and Adulterated Mathematics". :)

Visual Illusion: Snakes on a Plane

Enough is enough. I've had it with these ****** illusory snakes on this ******-****** plane.

(Tip of the cap to Maggie Koerth-Baker.)

Friday, March 16, 2018

Old Article: "On the Fracture of Pencil Points"

I got my first taste of solid mechanics (and fracture mechanics) as a kid when attempting to use 'Number 2' pencils, on which I gave up rather quickly. Once they break once, they will soon break again. I switched to "mechanical pencils" (I like the .07 size) when I was very young.

Here is an old article on pencil-tip fracture (by Henry Petroski). The picture below, which comes from an even earlier article, sets up the the geometry of a pencil tip.

(I was thinking about this because a 'Number 2' pencil showed up in The Grimm Legacy, which I am currently reading.)

Thursday, March 15, 2018

RIP Philip J. Davis (1923–2018) and Writing Uncountably Many Articles

Philip J. Davis, an applied mathematician and very prolific writer, died on Tuesday.

I have a pet peeve in the above obituary: Don't write sentences like "He wrote countless books, articles, and book reviews imbued with his personal perspective." in the obituary of a mathematician, especially if he is an analyst (with much work in numerical analysis, in this case). Trust me: it's countable (and, actually, it's finite).

For most of us, we'll be more familiar with the many essays and (especially) book reviews that Davis wrote for SIAM News.

(Tip of the cap to the SIAM Twitter account.)

"Title of a Paper"

Update: It turns out that I did this so quickly that I mixed my Oxford and UCLA affiliations. Oops.

Tuesday, March 13, 2018

Best. Erratum. Ever.

Because they have so many coauthors, one letter wrong in a name led to this. :)

(Tip of the cap to Nalini Joshi, whose 'liking' of this tweet led me to find it.)

Saturday, March 10, 2018

Playing Mario Kart on Google Maps to Celebrate Mario Day!

In celebration of Mario Day (Mar 10), Google is letting people play a version of Mario Kart on Google Maps.

I have a key question: Where are the best places to inflict lightning bolts on people?

In conclusion, come get some!

(Tip of the cap to Gabrielle Birkman, who indicates that there are places to get banana peels and turtle shells.)

The Multiplex Social–Slayage Network of Buffy the Vampire Slayer

Here is the multiplex social–slayage network of Buffy the Vampire Slayer.

This figure is definite fodder for talks. Also, if somebody sets up the adjacencies, we should compute some centrality and versatility measures.

Friday, March 09, 2018

Pure Evil Versus Applied Evil

The new SMBC is brilliant! I love the caption: "Most of the time when people call something pure evil, they're actually talking about applied evil." ;)

Feedback on Homework Assignments: Getting the Important Stuff Right

As part of the feedback that I once gave to Teaching Committee (to be passed on to the lecturer) on some of the mathematics material in Oxford, I once wrote: "dynamics: The Roadrunner's name is incorrect on homework sheet 2."

You've got to get the important stuff right.

(My submitted feedback also included more substantial comments.)

I also told the lecturer about this in person, of course. :)


New Word Proposal: "Scientificially"

I asked a student if a paper draft of mine passes muster with her "scientificially".

It was just a typo, but I may have to adopt this as a new word for when somebody does something artificial in science.

Example usage: "Those data were estimated scientificially to follow a power law."

Wednesday, March 07, 2018

Video project: "Faces of Women in Mathematics"

Last month, Irina Linke (Director) and Eugénie Hunsicker (Producer) collected videos of women mathematicians, and today they released their compilation video.

Quoting the project page: "In February 2018, women mathematicians from all over the world responded to a call for clips in which they were asked to introduce themselves. The result includes 146 clips of 243 women mathematicians from 36 different countries and speaking 31 different languages. Supported by the Committee for Women in Mathematics of the International Mathematical Union."

Take a look at the video!

I met Eugénie, a fellow Somervillian, at last summer's Somerville mathematics reunion (and informal Erdmann-fest). I just found out that she is also a fellow Project NExTer (i.e., a fellow 'dot').

Tuesday, March 06, 2018

"Hyperchaos" in the White House

I saw "CHAOS" trending on Twitter this morning, so I automatically looked it up, before seeing that it was about politics and then moving on to something else.

And now I see this article, which predominantly consists of an interview with nonlinear dynamicist (and pioneer of chaos) Jim Yorke, including discussions about both mathematical chaos and hyperchaos.

Here is how the part with Yorke begins: "That's not chaos, according to James A. Yorke, Distinguished University Professor of Mathematics and Physics at the University of Maryland at College Park." It goes on from there.

Just think about it: Jim Yorke, an expert in chaotic dynamics, was interviewed by CNN about Donald Trump, precisely because of the former's expertise in mathematical chaos. Yup, we've gone full Illuminati.

(Tip of the cap to Bruno Eckhardt and fuzzy sweatshirt particle.)

Monday, March 05, 2018

"Making Sense of Complexity": A Very Nice Introductory Comic Strip

Sarah Firth's comic strip, Making Sense of Complexity, provides a very nice introduction to complex systems.

Friday, March 02, 2018

Important Advice from Lego Grad Student to Prospective Graduate Students

Pay attention to this excellent advice from Lego Grad Student.

Reaction: YES! YES! A million times YES! (And, for the top tweet, I would change "seriously consider" to "absolutely go to".)

P.S. Lego Grad Student is awesome.

Playing "Soliton" in "Scrabble" (Lexulous)

Take a look at what I just played in “Scrabble” (Lexulous).

Proposal: Use Computational Topology to Study Aversion to Pictures of Holes

Clearly, we need to use topological data analysis (in which one tries to algorithmically compute things like holes and their generalizations) to study aversions to images of clusters of holes.

For science!

Thursday, March 01, 2018

Is 1 the Loneliest Number?

I like (several renditions of) the song "One (is The Loneliest Number)", but I get irked every time I hear following line "One is a number divided by two", because that is just a trivial existence statement.

(Some — most? — versions of the song actually have the line "One is the number divided by two", which is even worse, because of the "the".)

I suppose that this doesn't bother anybody else?

Is There a Mathematical Formula for How Long it Takes for a Child to Ask "Are We There Yet?"?

Well, I find the formula to be rather dubious, though I am highly amused to see it.

I was looking at Dwight Barkley's Wikipedia page, and I noticed that apparently he is also known for deriving an equation to estimate how long it will be until a child in a car asks the question "are we there yet?"

You can read about it (and see the equation) in this short article.

"Complex Contagions with Timers"

A new paper of mine just came out today. This paper was such a pain to write and the page proofs were also a royal pain, so it's a relief that it's finally out. Here are the details.

Title: Complex Contagions with Timers

Authors: Se-Wook Oh and Mason A. Porter

Abstract: There has been a great deal of effort to try to model social influence—including the spread of behavior, norms, and ideas—on networks. Most models of social influence tend to assume that individuals react to changes in the states of their neighbors without any time delay, but this is often not true in social contexts, where (for various reasons) different agents can have different response times. To examine such situations, we introduce the idea of a timer into threshold models of social influence. The presence of timers on nodes delays adoptions—i.e., changes of state—by the agents, which in turn delays the adoptions of their neighbors. With a homogeneously-distributed timer, in which all nodes have the same amount of delay, the adoption order of nodes remains the same. However, heterogeneously-distributed timers can change the adoption order of nodes and hence the “adoption paths” through which state changes spread in a network. Using a threshold model of social contagions, we illustrate that heterogeneous timers can either accelerate or decelerate the spread of adoptions compared to an analogous situation with homogeneous timers, and we investigate the relationship of such acceleration or deceleration with respect to the timer distribution and network structure. We derive an analytical approximation for the temporal evolution of the fraction of adopters by modifying a pair approximation for the Watts threshold model, and we find good agreement with numerical simulations. We also examine our new timer model on networks constructed from empirical data.