APIs for hardware : architecting cellphones and networks

We had two talks by here at UCSD on Tuesday. The first was Cell Phones: How Power Consumption Determines Functionality by Arvind, and the second was Software-Defined Networks by Nick McKeown. These talks had a lot in common: they were both about shifting paradigms for designers, and about approaching the architecture of hardware from a software point of view.

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More content-ful posts to come soon, I swear. I got sidetracked by job applications. ‘Tis the season, you know…

The REAL STORY of Alice and Bob. Classic investigative journalism (h/t Bikash Dey)

Tyler Perry’s For Colored Girls gets panned. I should mention that the play was done at MIT my first year there and I still remember it as one of the most affecting pieces of theater that I saw during my time there (and maybe after as well).

Scott McLemee on the poverty of the Rally to Restore Sanity.

Winners of the SD Asian Film Festival “Interpretations” contest. Like contentless scenes from your acting/directing class, but with film!

SAALT put out a report called From Macacas to Turban Toppers: The Rise in Xenophobic and Racist Rhetoric in American Political Discourse (PDF). Reading it is keeping me up past my bedtime. (via Sepia Mutiny).


The Hakawati (Rabih Alameddine) — an expansive novel, framed by the story of a son who has gone to the US coming back to visit his dying father in Lebanon. The sharply drawn tension and anguish of the present shifts rapidly through old family stories, to the story of Baybars (and parts in between). It’s hard to pick up the strands initially, but it’s a rewarding read once you get into it.

A Short History of the American Stomach (Frederick Kaufman) — a quick read, repeats of some stories from Harpers I had read. It might appeal to people who like Sarah Vowell’s writing, but it’s too heavy on snark for me. Good for picking up some cocktail-hour conversation pieces, if you enjoy talking about the puking habits of Puritans at cocktail hours.

The Magicians (Lev Grossman) — I enjoyed this book, even though some people call it Hipsters in Narnia. It is a bit of that, but I couldn’t really put it down (= brain candy). Recommended for those who want a jaded view of Harry Potter.

Ghostwritten (David Mitchell) — I read this one after reading Cloud Atlas, which I absolutely loved. It’s written in a similar style, with interlocking stories, but more direct storytelling going on than, say, if on a winter’s night a traveler. Maybe I just like the relay-race novel. In any case, definitely engrossing, if a bit… bleak? It’s simultaneously lush (descriptively) and bleak (psychologically).

Gaming the Vote (William F. Poundstone) — a popular nonfiction book about elections, the spoiler effect, and the history of voting systems. It’s larded with examples of elections from US history and makes for an engrossing read. Most of the focus is on the weaknesses of first-past-the-post and other methods of determining winners, but it’s a nice accessible read.

Nixing negative reviewers

A question came up while chatting with a friend — how do you tell the editors of the journal to not ask certain people for a review? Say you submit a paper to a journal and in the cover letter you want some language to the effect that “please don’t choose Dr. X as a reviewer, since they will be biased.” This must be a relatively common situation, especially where people have axes to grind, and what better way to grind them than while reviewing the other camp’s paper or grant proposal?

Let’s create a cartoon situation: suppose Dr. X really hates your guts (intellectually, of course) — this is actually the case, and not just your own misperceptions of Dr. X. I know that at some schools for tenure cases the candidate can give a list of people not to ask for letters. But in the context of paper submission, hows can you politely suggest that Dr. X may not be the most objective reviewer for your paper?


The fog in San Francisco (h/t Erin Rhode).

A general approach to privacy/utility tradeoffs, with metric spaces! A new preprint/note by Robert Kleinberg and Katrina Ligett.

Max breaks it down for you on how to use the divergence to get tight convergence for Markov chains.

The San Diego Asian Film Festival starts on Thursday!

Apparently China = SF Chinatown. Who knew? Maybe the fog confused them.

Mean absolute deviations for binomial random variables

Update: thanks to Yihong Wu for pointing out a typo in the statement of the result, which then took me months to get around to fixing.

I came across this paper in the Annals of Probability:

Mean absolute deviations of sample means and minimally concentrated binomials
Lutz Mattner

It contains the following cute lemma, which I didn’t know about before. Let S_n have binomial distribution with parameters (n,p). Let b(n,k,p) = \mathbb{P}(S_n = k). The first two parts of the lemma are given below.

Lemma. We have the following:

  1. k_0 \in \arg\max_{k \in \{0,\ldots, n\}} b(n,k,p) if and only if k_0 \in \{0,\ldots, n\} and (n+1)p - 1 \le k_0 \le (n+1) p.
  2. (De Moivre’s mean absolute deviation equality) \sum_{k=0}^{n} |k - np| b(n,k,p) = 2 v (1-p) \max_{k \in \{0,\ldots, n-1\}} b(n-1,k,p), where v is the unique integer between np < v \le np + 1.

The second part, which was new to me (perhaps I’ve been too sheltered), is also in a lovely paper from 1991 by Persi Diaconis and Sandy Zabell : “Closed Form Summation for Classical Distributions: Variations on a Theme of De Moivre,” in Statistical Science. Note that the sum in the second part is nothing more than \mathbb{E}|S_n - np|. Using this result, De Moivre proved that \lim_{n \to \infty} \mathbb{E}|S_n/n - p| \to 0, which implied (to him) that

if after taking a great number of experiments, it should be perceived that the happenings and failings have been nearly in a certain proportion, such as of 2 to 1, it may safely be concluded that the probabilities of happening or failing at any one time assigned will be very near in that proportion, and that the greater the number of experiments has been, so much nearer the truth will the conjectures be that are derived from them.

Diaconis and Zabell show the origins of this lemma, which leads to De Moivre’s result on the normal approximation to the binomial distribution. As for the proof of the L_1 convergence, they call the proof in the p = 1/2 case “simple but clever, impressive if only because of the notational infirmities of the day.” De Moivre’s proof was in Latin, but you can read a translation in their paper. A simple proof for rational p was given by Todhunter in 1865.

For those with an interest in probability with a dash of history to go along, the paper is a fun read.

Yellow Face at Mo’olelo Performing Arts Company

On Thursday I went to the last preview performance of Mo’olelo Performing Arts Company‘s production of Yellow Face, by David Henry Hwang. If you live in San Diego, go see it! It opened last night and plays through the end of the month.

Yellow Face poster

The play is a fictionalized autobiography, with Hwang as the main character, played by Greg Watanabe. Searching for an actor in his new play Face Value, Hwang casts Marcus G (Brian Bielawski), whom he thinks might be Asian. When he discovers Marcus is white, Hwang tries to give Marcus a backstory as a Siberian Jew (and hence Asian), but eventually fires him. The play flops weeks later, and Marcus and Hwang go their separate ways. Years later, Hwang discovers that Marcus has started to pass himself off as Asian and has become active and a bit of a celebrity in the Asian-American community, especially for political causes. Hwang finds Marcus toxic; he berates his ex for dating Marcus, he feels isolated. Hwang’s father and Marcus both become persons of interest in a congressional probe into Chinese financing in the US. In the end, of course, everything has to come out in the open.

In part, I read the play as Hwang dealing with the discomfort of being the spokesman for Asian-American theater and the expectations that come along with that. It also brings up the discomfort felt by Asian Americans (or anyone, really) when their struggles or concerns are co-opted by well-intentioned but overzealous white people. The historical context encompasses three moments in the 90’s : the casting in Miss Saigon of Jonathan Pryce, a white actor playing in yellowface, the 1996 campaign finance investigations into “Chinese influence” in US elections, and the 1999 railroading of Wen Ho Lee (the program has some dramaturgical notes in case you were asleep or too young in the 90’s). The play uses these events to frame Hwang’s vacillation between caring about the issues and being repulsed by Marcus’ involvement; Marcus uses his “yellowface” for good ends, but in the end he’s a poseur.

There’s a lot going on, and director Seema Sueko does a great job of keeping all the balls in the air while maintaining the narrative thread. The play is a farce, and while the madcap energy that the actors bring to their performances felt a little too extreme initially, in the end it felt necessary to keep the momentum going. I found the text a little uneven; the major climactic scene in which Hwang has it out with the yellow journalist from the NY Times is almost too measured and serious. Perhaps it’s the political climate we live in now — in a muckraking environment, an argument about blatant bias feels real, rather than absurd (or even hyperreal).

However, this production works well. All the technical details: the set, use of video projection, sound, lights, and so on, are well-suited to the space they have there. The ensemble (Albert Park, Michelle Wong, Jacob Bruce, and Maggie Carney) really work their butts off providing the diversity of performance and characterization needed to tell a decades worth of political and personal stories. Sueko uses the physical space of the theater to great effect, heightening the absurdity of situations, and using physical distance to complement and accent other sorts of “distance.”

So if you’re in San Diego, see this show — you’ll learn something!

UPDATE : I edited a bit above and realized that you could describe the NY times reporter as practicing “yellow journalism.” An implicit double entendre? I laugh!

UCSD is a new National Center for Biomedical Computing

Even though the main website hasn’t been updated yet, the NIH has funded a new National Center for Biomedical Computing here at UCSD, headed up by folks from the new Division of Biomedical Informatics. I’ve already been collaborating with some people from the DBMI, but I’m going to be doing work this year with the new center, named iDASH. It’s the only new center funded this year, and the only one from a public university, so we’re pretty excited about it!

Also, we need a logo!