Thoughts and Rants

3 Dec 2014:

The Two Paths

Every competent leader with the power to recruit and hire eventually faces an important decision regarding team size. There are two different schools of thought: (1) maximize total productivity and (2) maximize mean productivity. Maximizing total productivity implies a significantly larger group size: the leader would continue recruiting as long as there is positive marginal productivity. In contrast, maximizing mean productivity means recruiting only if marginal productivity is higher than the current mean productivity, and results in a ``lean and mean'' team.

I think everyone's natural instinct is to go for (1), but lately I've become a big fan of (2). In pursuing (2), the leader reduces the total output of the team (be it publications or sales revenue or whatever) by maybe 1/4 to 1/2, but increases morale because every team member is surrounded by smart and competent people. Thus, I would argue that (2) is better for team health and also better for companion retention. Additionally, there are boom and bust cycles in every field and market, and (2) is much better suited to survive downturns.

Reading/watching startup-related resources, it seems that (2) is the favored path for many entrepreneuers as well -- hire only when you really have to hire. But this makes me wonder about other academics with large groups who have spun out successful companies.

26 Nov 2014:

So, I checked all of the stocks that I bought and then later sold in the past two years today, and a majority of them continued increasing (in some cases by a huge amount, such as WDC). What this tells me is that I should leave well enough alone and learn discipline not to sell after a 30-50% gain.

Current portfolio: 15 stocks, 70% invested.

25 Nov 2014:

I have always been of the philosophy that whenever I hear the same suggestion from two different smart people who don't know each other, then it's time for me to take it (though, I have a really high bar for who I consider "smart people"). On one particular issue, I have resisted until now, mostly because I felt like it's too difficult. But with Independent Smart Person Suggestion #3, I think it's time to bite the bullet.

24 Nov 2014:

Thought of the Day:

A leader must continually work to discover and help realize the evolving goals and dreams of each of his companions.

9 Nov 2014:

I have always been of the opinion that it is not worth learning that which one does not intend to practice (which, of course, is why I failed a lot of courses in college). Since the days of Compacting in middle school, I have repeatedly trained myself to get lots of work done when deadlines are looming. It wouldn't make any sense to let that Ability go to waste now, right?

5 Nov 2014:

Sigh... a year full of missed resolutions:

Lose weight to 154 lb: missed by 4 lb.
Submit 3 papers from our group: submitted only Sherry's, looks like Jan at the earliest for Lucia's and Chunyan's.
Obtain 2 major grants: got 1, rejected by 9.
Outlicense IP to 3 companies: 1 executed, others are still too early to talk licensing.
Have business plan for startup: not even close, after recent change of direction.
Raise funding for startup: apparently we need a prototype instrument first.


Now, then, what about for the coming year?

26 Oct 2014:

Pumpkin Carving!

All of us, with our pumpkins.

All of us, imitating our pumpkins.

Sherry and her toxic pumpkin.

Lucia and her mischievous pumpkin.

Jin and his happy pumpkin.

Dave and his hear-no-evil pumpkin.

Pumpkins, all lined up`.

Pumpkins, scaring other pumpkins.

Pumpkins in the dark!

15 Oct 2014:

The Artist-Engineer

Despite many years of stereotyping artists as impecunious and impractical people, I have come to realize that I'm much more an artist than the typical engineer.

What is an artist? An artist is a person who has his own vision for what is beautiful and what is worthy of pursuit, and most crucially an artist is someone who is not hindered by discouragement from the outside world. In some sense, to be an artist is to be stubborn and true to oneself.

Taken to an extreme, the artist is the insular, tortured soul epitomized by van Gogh and others, but more moderate artists are found in every walk of life. A politician with a firm agenda not swayed by the mood swings of his constituency is an artist. A chef who refines his distinctive taste and flair rather than appealing to every customer and critic is an artist. A scientist who pursues research he deems worthwhile despite the opinions of journals and funding agencies is an artist.

At the other extreme is the engineer, who is typically characterized by an agnostic approach to solving problems presented to him by the outside world. Engineers are often quantitative, because without quantitation metrics it is not possible to weight the importance of different features and normalize the desires of different customers. Classical education strives, with mixed success, to train the masses into engineers, because historically there are barely enough people to solve the problems that need to be solved (e.g. getting these seeds into that dirt at this depth).

Distinct from both art and engineering is both creativity, the ability to come up with one's own novel approaches, and intelligence, the ability to quickly incorporate other's novel approaches. Whereas the artist-engineer spectrum is a tradeoff that is a matter of personal preference and predilection with no position being strictly better than any other position, creativity and intelligence are both decoupled and more of either is always desirable.

True, lasting greatness requires both an artistic drive and an engineering approach. Genghis Khan and Alexander the Great became who they were because they had a vision of what they wanted to accomplish, despite how unlikely that vision was at the outset, but to realize that vision they had to master military strategy, economic management, and political governence. Marco Polo and Christopher Columbus embarked on nigh-impossible voyages, but used the best tools and practices of their time to make these journeys possible.

Engineering is a reliable way of having a good life and doing good work, but good is often the nemesis of great. Once an engineer has established a good status, it becomes time to be less of an engineer and more of an artist; he should strive to be great, rather than just more good.


Somewhat related thought: I have respect for Yu Zheng; he pursues his own art and doesn't shy from controversy. It takes a lot more courage make a bastardized version of a great work than a faithful adaptation. Too many directors and producers cater to the whims of the fickle masses, not realizing that short-term success often stunts long-term greatness.


Apparently, I teach classes like I'm running a D&D game.

11 Oct 2014:

Doing my lab finances... we've spent $1.06 million in the first 15 months. o_O

28 Sep 2014:

(From XKCD)

Lol, I stared at that problem for a while trying to solve it... 3 shortest paths each 3 ohms, 8 paths with 1 detour at 5 ohms, 8(?) paths with 2 detours at 7 ohms... hm, there should be a recursion here that I can write/solve. Oh dear, I'm not going to finish my NIH proposal if I keep thinking about this.

Edit: Wait, I'm being silly, the number of paths should be non-decreasing, so the lower bound is at least 3 paths for each odd length >= 3 ohms. So current (I) is lower bounded by:

I > 3*(1/3 + 1/5 + 1/7 + ...)
> 1/1 + 1/2 + 1/3 + 1/4 + ...

The last is a harmonic series that diverges, so the current should be infinite, so effective resistance should be 0. (We would have gotten the same result on a 2 X infinite grid of resistors.)

Hm, OK, that was only 10 minutes or so.

23 Sep 2014:

Seen on the Internet:

    I have indentured my son, age 12, to help me mow our yard starting this summer. After the first go around he asked if there was a Roomba-like lawnmower. I told him there wasn't, that he could invent one, and that I would fund it. I also told him that until he did invent one he still had to help mow the lawn. "See a need, fill a need", nothing helps clarify product design faster.


I have great expectations for that kid!

13 Sep 2014:

Google-stalking Po always impresses me: recently, he's managed somehow to gather an obscene number of Hertz Fellows to co-found an online learning startup!


10 Sep 2014:

Dear Air Force Office of Sponsored Research, is it really a good idea to give only a form rejection email with no content feedback, some 8 months after you announce your winners online? I mean, we all spent a good 100 hours each on the grant; the least you could do is take 10 minutes to write a 3-sentence summary of why you rejected the proposal. Maybe you feel that the current funding climate is rough enough that there are people willing to repeatedly endure this abuse. But know that in doing so, you are selecting from the bottom of the barrel -- only PIs who are absolutely desperate with no other sources of funding are going to apply a second time. That is to say, not me.

15 Aug 2014:

Well, that was one of the most fun (literal) dreams I've had in a while:

A Negotiation with Myself

For inexplicable reasons, an identical copy of me came into existence (kind of like in the movie The Prestige). After quizzing each other to make sure that this wasn't a hoax, asking questions like "Who was your middle school Gifted teacher?", we trusted each other completely, because we knew all of each others' strengths, experiences, foibles, and frailties.

And then we got to negotiating. Clearly, there could only be one David Zhang, and the other must be Dan Zhang or some other suitably similar name. There will need to be a trip to Korea involved so that Dan will be visually distinguishable from Dave. Being Dan Zhang could be incredibly fun, because Dan would be completely free from all obligations and free to pursue any wild destiny. But being Dan Zhang would also be incredibly difficult, because he has no history, no background, and credentials. The down-side dominated the up-side, and if the choice was just like that, both of us would have wanted to continue being Dave. But there are ways to sweeten the deal.

I/we proposed that 35% of Dave's after-tax income from any source goes to Dan, no questions asked, while only 25% of Dan's income (if any) will go to Dave. Dave is morally obligated to help Dan as much as humanly possible to create a legal/social background. Plus, Dan can stay with Dave rent-free whenever he wants. That's almost good enough, but not quite -- it makes up for finances, but not for credentials. Dan would also need to be added as much as possible to papers and patents from Dave's lab in order to build reputation, and Dave is in charge of the icky job of arranging that with other parties. Dan's papers and IP filings, on the other hand, should not include Dave, so that Dan has maximal freedom to develop an independent reputation.

That got to the second hard part of the negotiation. Who else should know about Dave and Dan? Clearly, we would want to minimize the number of people who knew. Dad and Mom could provide much-needed resources, but may not be able to keep it absolutely secret. Wendy could definitely be trusted and should know. Costs and benefits for others had to be weighed; a few people might be able to provide help to create a background. For most, post-cosmetic surgery Dan would be just Dave's incredibly close and super smart friend.

In the end, the packages were balanced to the point that both Dave and Dan were very tempting. But since I/we don't believe in coin tosses to settle important decisions, we used the better game-theoretical method of bidding to determine who would be Dave... that is to say, how much am I willing to pay, on a one-time basis, to continue to be Dave? Funds from retirement accounts are available for bidding, but clearly not desirable to withdraw early, so if Dave bids over his liquid cash total, he will keep $5,000 in his bank account and only keep $1500 per month outside rent payments until the balance is clear.

The bids were as much about giving Dan a fair and reasonable set of starting conditions as a bid to continue being Dave. In the end, both of our bids were rather close, but we had roles assigned... and then we realized we forgot to stipulate the details of the cosmetic surgery. Since roles were already assigned (I won't say who I ended up being), interests were no longer perfectly aligned. Dave wanted Dan to look more different, whereas Dan would prefer to look more similar; Dan wanted Dave to pay for the surgery since looking different would be for Dave's benefit, but Dave wanted to split the costs. Dave and Dan still trusted each other and were friends, but also became business partners and negotiation counterparties.

2 Aug 2014:

Annoyed at BS market research reports... I'm looking at you, Professor Philip M. Parker.

1 Aug 2014:

Thought of the Day:

The epitome of lucid thinking is single-minded focus and simplicity; if an idea tries to solve three problems, then it is either a poor idea or three separate ideas. Strip away all the unnecessary parts. A slab of marble increases in value when it is carved into a statue.

27 Jul 2014:

"I fish only for edible fish, and hunt only for edible game, even in the laboratory."

                --Willis Carrier, inventor of air conditioning

26 Jul 2014:

Thoughts of the Day:

Moonlight (Chinese: 月光) is an unusual term in that in both English and Chinese, there's a secondary meaning not very related to the primary definition. In English, it means to undertake a secondary vocation in addition to the day job, whereas in Chinese, it means a profligate who has no money at the end of the month. The two meanings are, in some sense, opposites--except in the case of the entrepreneur.

The role of a Ph.D. advisor is that of a catalyst; each student's potential is determined by some combination of their creativity, intelligence, tenacity, integrity, and personal circumstances, but a good advisor helps them rapidly get to the level they can achieve.

24 Jul 2014:

Tell-tale sign of an entrepreneurial professor: All preliminary data in grant applications are at least 6 months old.

22 Jun 2014:

Live Again

If I should live again, what then would I be?
Scientist, soldier, or a calling not yet known?
Who will be my kith, my kin, and my enemy?
Would they remember me from actions this life sown?

Will my current name be in a history book,
For the future me to learn, respect or despise?
Or is now and this life but a note forsook,
In the cosmic grand symphony's reprise?

That sword in the stone I have yet to free,
That fire-breathing dragon I have yet to slay,
Will they both be there still waiting for me --
The future me on that faraway day?

Will I fall prey to the same traps and snares?
And be doomed to relive a Sisyphic life?
Perhaps fate has a number of hindrance spares,
And offer variety in destiny's strife.

The trusted partners and 知己 of today --
Tomorrow be they companions once more?
Is friendship cause enough for them to stay,
Or must they grow addicted to the soar?

Grows life easier or harder with each go?
The end must be planned before I begin.
Prudence and hope to weather crest and trough,
And patience to plan; all are needed for when I live again.

30 May 2014:

"One learns more through walking ten-thousand miles than through reading ten-thousand books."

                --Chinese proverb

The collorary to that is that one can learn nothing from either activity if not actively learning. For too long are we hearing without listening, viewing without seeing, browsing without reading, and doing without planning.

20 May 2014:

Thoughts of the Day:

A bargain isn't a bargain if it stays a bargain forever; the time windows for really great opportunities open and close rapidly.

Know well that which propels you forward, and that which holds you behind.

19 May 2014:

Note to self/others: NIH ERA Commons website is incompatible with Firefox; need to switch to Chrome in order to upload any PDFs...

18 May 2014:

"Sometimes you hear people say, 'When I'm at work, I do my work. But when I leave work, I don't think about it at all.' This type of person has a limited future in whatever he's doing. A person who does not think about his work when he is away from it is a person who is not suited to that line of work. If you are doing the right thing for you, your work and your personal life are interwoven, with only a thin dividing line between the two."

                --Brian Tracy, The Psychology of Selling

10 May 2014:

Thought of the Day:

Unless the Singularity actually happens, we each only have 30,000 days in our lives. We have to make each of them count!


Unrelated: I might get to work with another Hertz fellow in the near future! That's always exciting.

3 May 2014:

Thought of the Day:

I shall fear no failure; I may fall so that I better learn to run.

26 Apr 2014:

Physical robot experiments on sexual selection strategies; awesome in so many ways: Economist article or read the PLoS One paper. Gives new meaning to "chasing tail" :-P

24 Apr 2014:

A year ago, I would definitely not have predicted that I'd be traveling even half as much as I am now...

4 Apr 2014:

Thought of the Day:

There are no dead fields, only fields that have run out of smart and driven people.

23 Mar 2014:

Thought of the Day:

Be thankful for that which you have;
Be selective in that which you seek;
Be relentless towards that which you strive;
Be faithful unto those with whom you advance.


"There are two types of friends in life: the kind that when you go away for a long time and come back, it feels like nothing’s changed, and the kind that when you go away for a long time and come back, it feels like everything’s changed."

                                             - Mark Manson

Thanks for visiting, Grace! Glad to have you as one of the former group :) Though hopefully we'll see each other again without another 10 year pause...

14 Mar 2014:

xmax = 10;
ymax = 10;
for i = 1:dp
currx = (i-1)*xmax/dp;
for j = 1:dp
curry = (j-1)*ymax/dp;

Mmm... Curry...

11 Mar 2014:

Out of the Box

So, in the "Bargaining" MBA class that I've been auditing this term, I chatted with the instructor about the topic of creativity, and he gave me this puzzle, which for some weird reason or other I had never heard of before:

You have 6 coins laid out on the table like this:

   o o o

The challenge is to move one coin (and only one coin) so that the coins form 2 rows of 4 coins each. (Don't scroll down until you've had a chance to try this yourself, if you haven't heard it before!)

So, the first answer I came up with almost immediately is to rearrange it like this:
   o o

There's a row of 5 coins, which of course can be sub-divided into 2 overlapping rows of 4 coins, duh. Simple Mathcounts question. Well, turns out that defeats the spirit of the problem, it actually has to be two non-overlapping rows.

I came up with my second solution after thinking on it for about 10 minutes:

 q o o o

The idea being that the "q" coin is a coin that you take out of your pocket and put on the table. Apparently that's also cheating :/

After another 30 minutes or so, I came up with the "right" answer:

   S o o

Where S is the two coins stacked on top of one another. Somehow I didn't really like that answer though... the second coin is actually on another plane as the first, so it doesn't really form a "row" with either row. But, eh, I guess that's the standard "out of the box" solution. Does anyone know any other solutions?

(He also gave me the puzzle of "How do you get 12 people to all touch a rubber ball within 1 second?" To which, of course, I offered the violent Gordian solution of cutting the ball into 12 pieces... ^^)

2 Mar 2014:

"All men dream, but not equally. Those that dream by night in the dusty recesses of their minds wake in the day to find that it was vanity; but the dreamers of the day are dangerous men, for they may act their dreams with open eyes, to make it possible."

      -- T.E. Lawrence, "Lawrence of Arabia"

Amazingly appropriate fortune cookie today :)

22 Feb 2014:

"[He] believed in the green light, the orgastic future that year by year recedes before us. It eluded us then, but that's no matter -- tomorrow we will run faster, stretch out our arms farther ... And one fine morning --
So we beat on, boats against the current, borne back ceaselessly into the past."

      -- F. Scott Fitzgerald, "The Great Gatsby"

11 Feb 2014:

Got my first consulting check today! (Only $1500, but got to start somewhere...)

Thought of the Day:

Don't delay until tomorrow to do the things you'd rather do today.

9 Feb 2014:

Salad Days

As I was reading through various different company and market reports today, I was struck by how many Vice Presidents there are for each CEO. Subsequently, I realized that I haven't actually met any active CEOs of publicly traded companies in the past 10 years. But I did, 12 years ago, meet the then-CEO of Texas Instruments.

It was part of the now-defunct National Alliance of Excellence scholarship, which I saw randomly and applied to. In addition to some small scholarship amount (either $2k or $5k), it also offered the opportunity to try to arrange a meeting with anyone of my choice. At the time, I was still a ECE major at Caltech, and was thinking about a career in electronics/circuit design. So I asked to meet Thomas Engibous, the CEO of Texas Instruments. At the time, I had no idea about market caps or technology development; I simply had been using Texas Instruments calculators for something like 8 years, and thought it would be good to check out the company.

To my surprise, the National Alliance of Excellence actually managed to arrange a half-day meeting between me and Mr. Engibous. So I flew down to Dallas, had breakfast with the National Alliance of Excellence organizers, and then chatted with Thomas about my studies at Caltech and my career aspirations. He then offered me an summer internship on the spot, and introduced me to one of his up-and-coming engineers to be my supervisor for the summer. I accepted immediately.

I headed back to Caltech, and then started in Erik's lab as an undergrad researcher in the second semester of 2001, and liked it a lot -- but only about as much as the prospect of the TI internship. I was torn between my two options. But, sad (and embarassing!) to say, what decided for me wasn't a decision about which field to work in -- it was simply because I didn't want to deal with the hassle of trying to arrange for summer housing in Dallas (remember, this was back before the days of Craigslist).

Being utterly immature at the time, I delayed and delayed the decision until my agreed start date at TI, and I got a "No Show" email from the up-and-coming engineer. Having burnt that bridge, I then buckled down and got to work on DNA biomolecular engineering.

Thinking back upon it now, that was probably one of the biggest opportunities I botched due to being green in judgement. It's not that I regret having joined my current field, but rather that I should have handled the situation much better. If I had informed TI in a graceful and timely manner, then perhaps that connection would have stayed warm, and I'd be making integrated device in vitro diagnostics now.

26 Jan 2014:

Thought of the Day:

The quality of a person is not for himself to judge.

Saw randomly on the Internet:

Q: The pen is mightier than the sword; do you agree or disagree?

A: I don't understand this question; do you not know what a sword is?

20 Jan 2014:

It's been 10 years since I wrote my first patent... it's been a long, frustrating, lonely, and arduous journey, but I'm optimistic the lag phase is behind me now.

From "The Entrepreneur's Guide to a Biotech Startup" by Peter Kolchinsky:

"Venture capitalists' terms frequently include clauses that tax the founders and other shareholders in the event of missed milestones. For example, if a company fails to finish a prototype or secure a license by a certain date, the company must issue additional shares to the VCs, giving the VCs a larger stake in the company without additional investment. On the bright side, such terms really motivate management to succeed."

There's nothing like the feeling of rope burning beneath you as you climb.

13 Jan 2014:

"Vibrant companies must put together five-year plans. But they must be willing to change these five-year plans every single year." -- Bran Ferren, VP of Disney.

12 Jan 2014:

Romance of the Three Kingdoms

One of my favorite computer games growing up with Romance of the Three Kingdoms, which recreates China in the 3rd century A.D. as the carcass of the dying Han dynasty was being fought over by initially many, and finally three kingdoms. That game taught me very many things about management, including resource management, empire scaling issues, cultivating loyalty, putting correct people in correct roles, and the importance of constant (as opposed to unpredictable but spectacular) progress. In fact, it probably introduced to me at early age the concepts I would relearn in books like Good to Great.

But one features that I always wished they would put into the game (that they never did, despite 12 different versions) is ability discovery. The rulers of ancient China had no idea initially that Zhuge Liang had 100 INT or that Zhang Fei had 99 WAR... they were just some schmoes off the street. In contrast, the game gives you all the stats of all officers for free right away, and they are always the same for each officers through every game. That removes the very fun and highly replayable subgame of trying to figure out your newly hired officers' abilities without getting them killed/captured. And it also would have introduced would-be leaders to the importance of discovering and nurturing talent.

1 Jan 2014:

Thought of the Day:

Being an expert marksman only helps when you know exactly where the heart is; a machine gun is worth it when you can afford the bullets and tolerate the noise.

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