Results for “"optimal number"” 12 found
What is an optimal number of Pamplona bull gorings?
Two or more each year?:
Longtime runners voiced their frustration that the event had been “totally adulterated” and said it was time to “say enough to the distortion of the run”.
The problem for purists is not just that the run, known as the encierro, has become too safe — with only two gorings last year, the least since 1984 — but that the bulls are unable to break free from the highly trained steers that accompany them. This makes the adrenaline-fuelled race less dangerous but also less exciting.
“For the runners, this is the end of the encierro as they know it,” said Joe Distler, a semi-retired American who ran the bulls for 50 years and took part in the protest in solidarity.
For regular runners, a good day is when the bulls break free from the cabestros — the castrated steers that accompany them over the 875-metre course to the city bullring — and one can feel the adrenaline-drenched thrill of running half a block directly in the front of a bull’s horns before letting it pass.
Here is more from Ian Mount at the FT. As you wish folks, but I for one am content to live “inside the algorithm.”
What’s the optimal number of book reviews?
Virginia Postrel writes:
As an author, I want more book reviews; quantity matters more than
quality when you’re going for sheer exposure. But as a reader, I only
want more interesting reviews, particularly of books I’m not likely to
learn about otherwise.
Newspaper book reviews, of course, are declining in number. Here is New York Times coverage of the phenomenon.
I can think of three functions for book reviews:
1. They help people learn about good books. If this is true, we should expect a market optimum.
2. No one much uses book reviews, but they make newspapers feel like more prestigious products. In this case book reviews would be an inefficient form of product differentiation by making The New York Times appear more different from The New York Post than readers ideally would like. There would be too many book reviews.
3. People use book reviews as a substitute for reading the books themselves. I call this "book reviews as signaling." Abolish the reviews and either a) people will have to go read the books (an even more wasteful form of signalling), or b) people will forget about literary matters altogether, which lowers signalling costs.
I use book reviews as I would use ads for books and blurbs for books. I just want the bottom line. I would be happier if newspapers published many more one-paragraph book reviews, but with very clear and definite evaluations. Entertainment Weekly does just this, although I find their taste in books unreliable. Nonetheless I am not alone in my preference, and I believe that few people read long book reviews. That makes me think there is something to #2.
Safari surprises
I learned just how accustomed I am to North American wildlife patterns. In much of North America, you see wildlife only sporadically, as for instance in Yellowstone Park you can easily drive for an hour and not see a bear.
In this part of Masai Mara, it is unusual to drive for more than thirty seconds without seeing something interesting. And very commonly you can see a tableau of multiple animals, such as buffalo, Thomson’s gazelle, warthogs, and zebras, all together at once.
On those 4-5 hour drives around the plains, usuually I am thinking about “solving for the equilibrium.” When you see a group of dik-diks, the immediate thought is “how do they escape the cheetahs?” You wonder what is the optimal number of a buffalo grouping to repel a lion attack, without crowding or overgrazing on a particular patch of land.
How close can your open vehicle come to the lions without arousing excessive interest? (Closer than you might think.)
When should a pride of lions split into two groups, balancing strength of collective attack against food scarcity?
Why do cheetahs go about it solo? And how is that fact related to their propensity to win chases on the basis of extreme bursts of speed?
Can you model why the zebras and wildebeest seem to get along so well together?
What is the deadweight loss from the fact that wildebeest use property allocation — over which the males fight — to attract females?
I have noticed that the guides are implicitly Lamarckian in their theorizing.
As dusk arrives, many of the larger cats become more active. And so the potential prey wake up and move to more open territory, where they can see predators arriving. They group and spread themselves out (optimally?), to maximize their own collective field of vision and aural acuity, in case a predator should approach. Those patterns are gone by the late morning.
There is definitely a set of land value gradients here, noting that waterholes are both a) super-valuable, and b) the place where you are most vulnerable to predators. Few potential prey wish to settle there, though they will visit and make haste to leave.
I enjoy watching the prey trigger equilibrium of “My durability in running speed exceeds yours, so I can hang around and expect you won’t charge me, at least not if I keep a safe enough distance. Furthermore, if I don’t run away I can keep you in plain view, which is preferable in any case.”
So my biggest surprise is how visible the notion of equilibrium is here.
Tuesday assorted links
1. China fact of the day — what if China stops buying Treasuries?
2. “A few fire ants spaced well apart behave like individual ants. But pack enough of them close together, and they act more like a single unit, exhibiting both solid and liquid properties. They can form rafts to survive flash floods, arrange themselves into towers, and you can even pour them from a teapot like a fluid.” Link here.
3. Donald Kohn on Sumner and ngdp targeting. And Sumner’s response.
4. Is 20 quadrillion the correct number of ants? The optimal number of ants?
5. Supply curves slope upward.
6. Niger projection of the day (FT): “On current trends, Niger’s population is on course to nearly triple from about 24mn in 2020 to a projected 68mn in 2050, according to the UN Development Programme’s latest forecast. If that projection proves correct, Niger’s population will have grown 25 times in the century to 2050, a period over which the global population will have risen a relatively modest fourfold.”
Richard Davis requests
Here are some answers, I put his questions — from Request for Requests – in bold:
Melancholy among academics.
We’re a pretty sorry bunch, and many of us don’t have so much professionally to live for, at least not at the relevant margin — it is easy to lose forward momentum and never recover it, given the constraints and incentives in the profession and broader pressures toward conformity. Rates of depression in academia, and especially in graduate school, are fairly high. Many of the core processes are demoralizing rather than inspiring. It is remarkable to me how much other people simply have accepted that is how things ought to be and perhaps they believe matters cannot be that different. I view the high rates of depression in academic life as a “canary in the coal mine” that doesn’t get enough attention as an indicator of bigger, more systemic problems in the entire enterprise. What are you doing with your lifetime sinecure?
Your favorite things Soviet.
Shostakovich. And the Romantic pianists, most of all Richter and Gilels. Constructivist art and ballet up through the late 1920s. The early chess games of Tal. Magnitogorsk. War memorials, most of all in Leningrad. Tarkovsky. I admire the “great” Soviet novels, but I don’t love them, except for Solzhenitsyn, whom I would rather read then Dostoyevsky. Probably the poetry is amazing, but my Russian is too limited to appreciate it.
The optimal number of math PhDs worldwide.
I would think fairly few. I am happy having lots of mathematicians, with independent tests of quality. But is the Ph.D such a great test or marker of quality? Did Euclid have one? Euler? Does it show you will be a great teacher? Maybe we should work toward abolishing the math PhD concept, but out of respect for the profession, not out of hostility toward math.
What historical works of art were anticipated to be great prior to creation, were immediately declared to be great at creation and have continued to be judged great ever since?
Overall it is striking how popular how many of the great revolutionaries have been. Michelangelo was a major figure of renown. Mozart was quite popular, though not fully appreciated. Beethoven was a legend in his time, and every Wagner opera was an event. Goethe ruled his time as a titan. A significant percentage of the very best writers were well known and loved during their careers, though of course there was uncertainty how well they would stand up to the test of time.
The future of Northern New Jersey.
Much like the present, plus defaults on the pension obligations and over time the Indian food may get worse, due to acculturation. The Sopranos will fade into distant memory, I am sorry to say, as will Bruce Springsteen. So many young people already don’t know them or care. I feel lucky to have grown up during the region’s cultural peak.
Who are the greats that still walk among us (other than McCartney)?
The major tech founders and CEOs, Stephan Wolfram, Jasper Johns and Frank Stella and Richard Serra and Gerhardt Richter and Robert Gober, a number of other classic rock stars (Dylan, Brian Wilson, Jagger, Eno, etc.), Philip Glass, Richard D. James, and note most of the greatest classical musicians who have ever lived are alive and playing today (Uchida anyone?), at least once Covid goes away. Many of the major architects. Ferrante and Knausgaard and Alice Munro. Many of the figures who built up East Asia and Singapore. Perelman. Jerry Seinfeld and Larry David. Magnus Carlsen and all sorts of figures in sports. A bunch of other people whom Eric Weinstein would list.
Why
Why not?
What professions are oversaturated?
Chad writes me:
What jobs (particularly ones we think of as being inherently beneficial to society) might America have too many of? Political journalism comes to mind this particular month, since we apparently have enough to carefully monitor the Chipotle orders of presidential candidates 19 months before the election. Writers might be another, particularly in a world of self-publishing.
One can imagine lots of reasons for a greater-than-optimal number of people in a particular profession, from government subsidies to cultural biases, but I’m curious if you have a gut feeling about any professions in particular.
A good question, in my view the answer is not so simple. Writers and artists are indeed a possible nomination, but some of the demand for these professions is likely for consumption, which makes the overinvestment difficult to judge. And what about lawyers? Relative to the number of laws and regulations (too many in my view, but take them as given), it is not obvious to me that we have too many lawyers. Someone has to tell companies when it is safe to proceed, or not.
How about too many people selling medical devices and other high margin items? Too many people making alcohol? Too many people raising and selling animal meat? Those would be my picks.
The finance sector is another obvious culprit, but as a fraction of wealth I do not think it is larger than in the past. Admittedly people in the finance sector may be engaging in the wrong activities, but I am not sure the case for fewer employees per se is so obvious. Still, it is another candidate, if only because it (often) involves people selling high-margin items.
Make three claims when trying to persuade
Suzanne B. Shu and Kurt A. Carlson have a paper (pdf) on this claim:
How many positive claims should be used to produce the most positive impression of a product or service? This article posits that in settings where consumers know that the message source has a persuasion motive, the optimal number of positive claims is three. More claims are better until the fourth claim, at which time consumers’ persuasion knowledge causes them to see all the claims with skepticism. The studies in this paper establish and explore this pattern, which is referred to as the charm of three. An initial experiment finds that impressions peak at three claims for sources with persuasion motives but not for sources without a persuasion motive. Experiment 2 finds that this occurs for attitudes and impressions, and that increases in skepticism after three claims explain the effect. Two final experiments examine the process by investigating how cognitive load and sequential claims impact the effect.
Here is a NYT summary of those results.
Do scholars produce too much and revise too little?
Art Carden asks me:
…do you think scholars spend too much time producing new content and too little time revising and refining their arguments? I’m thinking about the Scholars of Old (e.g. Smith) taking their work through multiple editions. Thomas Sowell is good about producing revised versions of some of his books, but a glance at my shelf makes me wonder if Eminent Scholar should’ve revised his/her first book instead of writing a second or third or fourth.Do you think books go through the optimal number of revisions? Is the editing process so good today that the first edition usually should be the last?
In music, Brahms is notorious for having spent a lot of time revising his drafts. Pierre Boulez explicitly revised and improved many of his pieces, after adding in years of extra work. Stravinsky’s later 1947 version of Petrouchka is much sharper and cleaner than his 1911 release. In all of these cases the revisions are worthwhile, because these works were very special and worth improving. Brahms’s first symphony might have done better with some further revisions yet.
When it comes to economics, individual works are less and less special all the time, unlike in the days of Adam Smith. Smith waited, more or less perfected his book, and in the meantime he was not really scooped. Today it is the collective body of work which carries the force. We also live in the age of the working paper, where it is the first released draft which matters most. There is an institutional failure that first released drafts are released too soon, for the purposes of receiving attention and credit. Yet I don’t think there is a corresponding problem of too few editions of the working paper. Ideally there should be no more than two. A first “here I am” version, to stimulate discussion and feedback, and eventually a final version which maximizes accuracy.
In fact if scholars had to commit to only two versions of the paper, they might be induced to make the early release more accurate in advance, knowing they cannot magically revise away errors a week later with the magic of word processing and web re-posting. This move toward fewer editions would offset some of the costs of premature release. Again, we do not see a case where a greater number of revisions would be better.
The scarcity of attention is the key reason why a very small number of accuracy-enhancing revisions is more or less optimal.
Inner Peace with Economics
The optimal number of lifetime speeding tickets is greater than zero.
Does the quality of blog comments deteriorate?
Forget about MR and its superb commentators, I am talking about the typical above-average blogs. I often have the impression that the best comments come in the first fifteen or so, after which quality declines precipitously and often exponentially. Why might that be?
1. The truly smart people only like to make smart points on "fresh" posts. For instance more people read the comments on fresh posts (but why?), so the
benefit of a quality comment is lower as the post becomes older.
2. As time passes, the chance that a warring twosome find each other, and take over the thread, increases.
3. There is a tendency to attack or respond to the stupidest or most controversial thing said, and the longer the comments thread runs for, the stupider this will get.
4. As the number of comments multiplies, so does the number of independent discussion threads and the optimal number of threads is exceeded.
5. (Addended) As one (early) commentator notes below, the simple fact of diminishing marginal utility.
Might some of these mechanisms also help explain why a) history of thought is "ghettoized" as a field, and b) there is such a high premium to working in hot, new fields? The general point is that there are increasing returns to scale for high quality discussions; furthermore those quality discussions are quite fragile and require cultivation and subsidization through norms. Freshness matters, so stale topics will indeed encounter discrimination.
Comments are open, who wants to go first?
Are we predisposed to be excessively hawkish?
Daniel Kahneman and Jonathan Renshon argue we are too quick to pick a fight:
Social and cognitive psychologists have identified a number of predictable errors (psychologists call them biases) in the ways that humans judge situations and evaluate risks. Biases have been documented both in the laboratory and in the real world, mostly in situations that have no connection to international politics. For example, people are prone to exaggerating their strengths: About 80 percent of us believe that our driving skills are better than average. In situations of potential conflict, the same optimistic bias makes politicians and generals receptive to advisors who offer highly favorable estimates of the outcomes of war. Such a predisposition, often shared by leaders on both sides of a conflict, is likely to produce a disaster. And this is not an isolated example.
In fact, when we constructed a list of the biases uncovered in 40 years of psychological research, we were startled by what we found: All the biases in our list favor hawks. These psychological impulses–only a few of which we discuss here–incline national leaders to exaggerate the evil intentions of adversaries, to misjudge how adversaries perceive them, to be overly sanguine when hostilities start, and overly reluctant to make necessary concessions in negotiations. In short, these biases have the effect of making wars more likely to begin and more difficult to end.
Since the first-best, optimal number of wars is zero, this is correct. The more difficult and also more important question is whether "the good guys" fight too many or too few wars, given this strong martial propensity of "the bad guys," and treating the bad guys as the first movers. Another bias is that some "just wars" (but can they succeed?) remain unfought, usually when we do not care much about the slaughter of "out-group innocents," as evidenced by Timor, Rwanda, Darfur, etc. The U.S. entered World War II too late rather than too early, and did too little to limit the Holocaust.
Of course we need to adjust any estimate by the probability that we are sometimes "the bad guys" rather than "the good guys."
Here is one critical comment, here is Matt Yglesias. Dan Drezner offers commentary.
Comments are open, but the discussion will be better if we consider the biases rather than debating the merits of particular wars.
UHaul Pricing and Free Drinks for Women Nite
Here is my analysis of UHaul pricing and the larger implications for not only ‘women drink free nites’ but many other markets.
Why is it so more expensive to rent a UHaul van to travel from LA to Las Vegas ($454) than from Vegas to LA ($119) (more here). Since the direct cost is similar the first thing an economist might think of is price discrimination. But the rental market is highly competitive, especially when we take into account substitutes such as train, private car etc., so that seems like a non-starter. A good answer needs to recognize that UHaul operates a network with significant inter-customer externalities.
Let us suppose that as the day dawns UHaul has the optimal number of trucks at each of its locations. At the end of the day, UHaul would like the same number of trucks at each of its locations. But this is possible only if departures equal arrivals and to help achieve that balance UHaul lowers the price on the low demand Vegas to LA trip and raises it on the high demand Vegas to LA trip. (It’s more complicated than this because there are many more than bi-directional considerations but you get the idea.)
Put differently, a customer who travels from Las Vegas to LA reduces the cost to UHaul of running its network because it lets UHaul sell an LA to Las Vegas trip. The direct costs may be similar but the indirect costs related to running the network are very different. UHaul’s pricing strategy reflects both the direct and indirect costs.
Network economics has some similarities to platform economics. A bar, for example, is a platform which mediates transactions (pecuniary and non-pecuniary!) between two sorts of customers, men and women. If men have a higher demand for going to a bar with many women (LA to Las Vegas) than women have of going to a bar with many men (Las Vegas to LA) then in a competitive market the bar must set a higher price for men than for women. In this context, far from being an example of monopoly power, differential pricing is a result of competition.
More generally, there are many examples of platform markets. The developer of a mall has as customers shoppers and shops. A video game console sells itself to players and programmers. A credit card must have users and merchants. In some places differential pricing for men and women at nightclubs is illegal. But in a platform market such differential pricing can make both men and women better off. Similar things can be said about practices in other platform markets which look anti-competitive at first glance but in fact are the result of competition in the context of a platform.
More on platform economics, also called two-sided markets, in Rochet and Tirole.
Bonus points to Larry White, Mark Weaver and Michael Stack for sending in answers and double bonus points to Larry for suggesting that some of theory could be tested by looking at drink pricing at gay bars.