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People are not rational maximisers of von Neumann-Morgenstern utility

Here are two examples:

  • At every sandwich shop in Britain (Pret A Manger, Eat, etc), when you attempt to pay for your sandwich you will be asked if you will be eating in or taking the food out of the shop.  The reason is that, thanks to the complexities of the UK tax system, the shop is meant to pay VAT if you dine in, but they don’t have to if you take it out.

    The shop doesn’t care in the slightest whether you actually eat in or out. So long as they’ve asked you about your intentions, they’re legally covered.  The upshot is that for anybody actually intending to eat their sandwich in the shop, the rational thing to do is to say that you’re taking it out and then eat in the shop anyway.  If anybody asks why you chose to do so, simply explain that you changed your mind. Since the sandwich shop doesn’t care, the probability of being caught is zero; and since you can always say that you changed your mind even if you were, the cost of being caught is precisely none.  Hence, the rational von Neumann-Morgenstern expected utility maximiser should never pay more than the take-out price. But people do …

  • When you book cinema tickets online, you have the option of selecting a student discount.  Cinemas love online bookings because you then collect your ticket from a machine instead of a person.  That means that they’re free to either hire one less person, or put the person saved onto the candy counter.  It also means that they can have ticket collection take up less space and expand the candy counter (where all the fat profit margins are located).You do not need to show a student card when collecting your ticket from the machine at the cinema.

    You do not need to show a student card when entering the cinema with your ticket.  You can, in fact, claim a student discount without any risk of being asked to prove that you are actually a student.  But people don’t …

Both of these examples are of price discrimination by a monopolist.  In the second example, the Cinema is the discriminator, charging less to students because students, in general, have a lower willingness to spend than non-students.  In the first example, the UK government is the discriminator.  The people with the lower willingness to pay are those that are prepared to take their food out rather than dine in.

In standard economic theory, both examples should succeed only if a) people are risk averse — which, in general, they are — and b) there is a non-zero chance that a “cheater” will get caught and suffer some loss as a result.  Even then, the probability-weighted loss from being caught would need to exceed the probability-weighted gain from successfully “cheating”.

But since the probability of being caught in these examples is zero and, with the sandwich shop, at least, the loss from being caught is also zero, the theory breaks down here.

I suspect that even Loss Aversion, a consequence of Prospect Theory, would fail to explain people’s behaviour here because we are talking about zero-probability events.

I don’t think we can avoid including social norms and ethics to explain them.  People have a socially-conditioned aversion to lying (saying that you will take the food out when you really intend to eat in; saying that you’re a student when you’re not) and this is what offsets the gain from the deception.  It also pretty clearly depends on the size of the gain relative to some internal scale.  A non-student with a low income is more likely to pretend to be a student than someone with a high income.

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A blast from the past

Back in June of 1987 (!), the New York Times interviewed Edward W. Kelley Jr. just as he joined the Federal Reserve’s board of governors.  How’s this for a quote?:

Q. Mr. Volcker has been considered something of a foot-dragger on bank deregulation. Where do you stand?

A. I’m philosophically in favor. The deregulation we’ve had over the last few years has been highly beneficial and I would favor further deregulation of the financial services industry. But there’s an overriding public interest in making sure the integrity of those types of institutions is maintained. I really do not want to run any meaningful risks that we deregulate at a speed or in a way that would imperil that.

Brilliant!

[Hat tip to my new favourite blog (ok, so I’m two years behind the times), Economics of Contempt]

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Obama’s (i.e. The Volcker) bank plan

Those of us who aren’t American but still follow U.S. politics were quietly giggling (okay, openly guffawing) into our latte’s last week when Scott Brown won the special election to replace the late Ted Kennedy.  The Daily Show’s take on the whole affair (I think it was broadcast the night before the election day) was spot on and I urge anyone with the capability to hunt down that episode.  In short, the Democrat’s handling of the event is a classic example of why the word clusterfuck was invented. What in blazes they now intend to do in passing any reasonable kind of reform in health-care (and the ideas on the table weren’t really all that reasonable to start with) is beyond me.

Anyway.  I tip my hat to the newest federal Senator in the United States for an expertly handled campaign.

I was then surprised to (finally) see some equally smart politics from the White House in the form of Obama publically supporting the banking regulation ideas of former Fed chair and octogenarian, Paul Volcker.

The White House had already been making noises about imposing a fee on financial institutions to recoup any losses in TARP.  TARP, if you remember, is the US$700 billion officially set aside under president Bush Jr. to help the finance industry weather the storm.  Of course, a large fraction of TARP was diverted to help the car (that’s “auto” for any Americans in the audience) industry and not all assistance to the financial industry was included in TARP.  Still, it’s the closest thing to an easy target with a pronounceable name.  If you care, you can read my incredibly brief thoughts on the levy here and, more importantly, here.

But the Volcker plan is an entirely different kettle of fish and can be boiled down to a simple and beautiful phrase:  “Too big to fail is just too big.”

It calls for constraints on the scope and the size of US banks.  It seeks to ban proprietary trading at institutions that hold retail deposits.  It’s an armchair commentator’s wet dream come true!  It’s also, unfortunately, staggeringly unlikely to ever become reality.  There are two reasons for this.

First, as expertly described by the Economics of Contempt, the White House has no intention of pushing this through anyway.  Instead, it was …

… a fairly transparent political stunt — the White House needed to do something to take the media’s focus off of health care 24/7, so they flew in Volcker and announced some proposals that sound good to the media. The two Senate staffers I talk to regularly both said their offices were basically ignoring Obama’s proposals, because even if the White House fights for them (which they won’t), Chris Dodd has no intention of inserting them into his committee’s bill. I like how some people think Obama’s proposals represent a fundamental turning point on financial reform, because….well, clearly this is their first rodeo. (Hence the uber-quixotic language they use to describe financial reform.)

[Update: Just to clarify, when I said Obama’s announcement was a “fairly transparent political stunt,” I wasn’t criticizing the Obama administration. We live in a political world, and political stunts are often useful. If I were Rahm Emanuel, I’d be a dick have done the same thing. I think it was probably a savvy move, and if health care reform ends up passing, then it was worth it.]

Second, the U.S. Supreme Court, in the second move in the space of a week to leave the America-watchers of the world chuckling, decided to reverse decades of precedent and assert that when it came to political speech, corporations, unions and other groups of individuals have more power than individuals.  Not only can corporations, unions and the like directly fund political campaigns, but unlike individuals, they are subject to no limit on their donations.  It’s great.  You’re going to end up seeing major political events sponsored by Pepsi.  You’re going to have unlimited funding available to opponents of any politician that does anything that runs contrary to a company that employs people in his or her district or state.  In short, you will never, ever again see anything serious passed in an election year in the United States unless it has not just bipartisan, but unanimous support.

So, no, as much as I like what Obama said, I don’t think it’ll ever become law.  It certainly won’t in 2010.

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Epistemology in the social sciences (economics included)

I’m not sure how I came across it, but Daniel Little has a post summarising a 2006 article by Gabriel Abend:  “Styles of Sociological Thought: Sociologies, Epistemologies, and the Mexican and U.S. Quests for Truth“.  Daniel writes:

Abend attempts to take the measure of a particularly profound form of difference that might be postulated within the domain of world sociology: the idea that different national traditions of sociology may embody different epistemological frameworks that make their results genuinely incommensurable.

[…]

Consider this tabulation of results on the question of the role of evidence and theory taken by the two sets of articles:

[…]

Here is a striking tabulation of epistemic differences between the two samples:

Abend believes that these basic epistemological differences between U.S. and Mexican sociology imply a fundamental incommensurability of results:

To consider the epistemological thesis, let us pose the following thought experiment. Suppose a Mexican sociologist claims p and a U.S. sociologist claims not-p.  Carnap’s or Popper’s epistemology would have the empirical world arbitrate between these two theoretical claims. But, as we have seen, sociologists in Mexico and the United States hold different stances regarding what a theory should be, what an explanation should look like, what rules of inference and standards of proof should be stipulated, what role evidence should play, and so on. The empirical world could only adjudicate the dispute if an agreement on these epistemological presuppositions could be reached (and there are good reasons to expect that in such a situation neither side would be willing to give up its epistemology). Furthermore, it seems to me that my thought experiment to some degree misses the point. For it imagines a situation in which a Mexican sociologist claims p and a U.S. sociologist claims not-p, failing to realize that that would only be possible if the problem were articulated in similar terms. However, we have seen that Mexican and U.S. sociologies also differ in how problems are articulated—rather than p and not-p, one should probably speak of p and q.  I believe that Mexican and U.S. sociologies are perceptually and semantically incommensurable as well. (27)

Though Abend’s analysis is comparative, I find his analysis of the epistemological assumptions underlying the U.S. cases to be highly insightful all by itself.  In just a few pages he captures what seem to me to be the core epistemological assumptions of the conduct of sociological research in the U.S.  These include:

  • the assumption of “general regular reality” (the assumption that social phenomena are “really” governed by underlying regularities)
  • deductivism
  • epistemic objectivity
  • a preference for quantification and abstract vocabulary
  • separation of fact and value; value neutrality

There is a clear (?) parallel dispute in the study of economics as well, made all the more complicated by the allegations leveled at economics as a discipline as a result of the global financial crisis.

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Nassim Taleb takes bat, ball; goes home

The author of The Black Swan doesn’t approve of the looming reappointment of Ben Bernanke as chairman of the US Federal Reserve.  Writing in the Huffington Post, he says:

What I am seeing and hearing on the news — the reappointment of Bernanke — is too hard for me to bear. I cannot believe that we, in the 21st century, can accept living in such a society. I am not blaming Bernanke (he doesn’t even know he doesn’t understand how things work or that the tools he uses are not empirical); it is the Senators appointing him who are totally irresponsible — as if we promoted every doctor who caused malpractice. The world has never, never been as fragile. Economics make[sic] homeopath and alternative healers look empirical and scientific.

No news, no press, no Davos, no suit-and-tie fraudsters, no fools. I need to withdraw as immediately as possible into the Platonic quiet of my library, work on my next book, find solace in science and philosophy, and mull the next step. I will also structure trades with my Universa friends to bet on the next mistake by Bernanke, Summers, and Geithner. I will only (briefly) emerge from my hiatus when the publishers force me to do so upon the publication of the paperback edition of The Black Swan.

Bye,
Nassim

That’s quite a god complex Taleb’s got going on there (“he doesn’t even know he doesn’t understand how things work”).

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Food stamps in America

Here is a NY Times article doing what the NY Times does well, this time looking at the use of food stamps across America.  Here are the basic details (emphasis is all mine):

With food stamp use at record highs and climbing every month, a program once scorned as a failed welfare scheme now helps feed one in eight Americans and one in four children.

It has grown so rapidly in places so diverse that it is becoming nearly as ordinary as the groceries it buys. More than 36 million people use inconspicuous plastic cards for staples like milk, bread and cheese
[…]
the program is now expanding at a pace of about 20,000 people a day. There are 239 counties in the United States where at least a quarter of the population receives food stamps
[…]
Nationwide, food stamps reach about two-thirds of those eligible, with rates ranging from an estimated 50 percent in California to 98 percent in Missouri. Mr. Concannon urged lagging states to do more to enroll the needy, citing a recent government report that found a sharp rise in Americans with inconsistent access to adequate food.
[…]
Unemployment insurance, despite rapid growth, reaches about only half the jobless (and replaces about half their income), making food stamps the only aid many people can get — the safety net’s safety net.

Support for the food stamp program reached a nadir in the mid-1990s when critics, likening the benefit to cash welfare, won significant restrictions and sought even more. But after use plunged for several years, President Bill Clinton began promoting the program, in part as a way to help the working poor. President George W. Bush expanded that effort, a strategy Mr. Obama has embraced.

The revival was crowned last year with an upbeat change of name. What most people still call food stamps is technically the Supplemental Nutrition Assistance Program, or SNAP.
[…]
Now nearly 12 percent of Americans receive aid — 28 percent of blacks, 15 percent of Latinos and 8 percent of whites. Benefits average about $130 a month for each person in the household, but vary with shelter and child care costs.
[…]
Use among children is especially high. A third of the children in Louisiana, Missouri and Tennessee receive food aid. In the Bronx, the rate is 46 percent. In East Carroll Parish, La., three-quarters of the children receive food stamps.

A recent study by Mark R. Rank, a professor at Washington University in St. Louis, startled some policy makers in finding that half of Americans receive food stamps, at least briefly, by the time they turn 20. Among black children, the figure was 90 percent.

I’m not sure how I feel about food stamps.  The classically-trained economist in me wants to point out that money is fungible, so that:

  • for people that, if they were given the equivalent amount of cash, would have bought the same amount of food,  the program largely serves to impose unnecessary administrative costs over a simple cash transfer and places a stigma on the recipients; and
  • for people that, if they were given the equivalent amount of cash, would have bought less food, the program (arguably) willfully deprives them of welfare in addition to the administrative costs and stigma.

On the other hand, we have that:

  • for the (presumed) minority of recipients that have problems with drug or alcohol abuse or have a family member that has problems, receiving aid in the form of food stamps helps ensure that there’s still food on the table (although I do assume that there is a secondary market in food stamps, not to mention in food itself);
  • for the recipients living in high-crime areas, the incentive to steal food stamps is lower than that to steal cash (even if there is a secondary market, it’ll be annoying to deal with and won’t give 100 cents on the dollar), so receiving food stamps is safer;
  • by giving people food stamps instead of cash, you reduce the possibility of a sense of entitlement emerging (one of the major problems in countries, like Britain, with comprehensive welfare systems is that recipients can come to consider the aid they receive as their right and not just (hopefully temporary) assistance); and
  • America, for some reason that is mostly beyond me, has always had trouble facing up to the moral imperative to assist those in genuine need and presenting that assistance as food stamps seems to have granted it some political cover.

Anyway, the NY Times piece comes with some more fantastic graphics.  Here are two snapshots (click-through on either of them to get to the good stuff on the NY Times website):

NYTimes_Foodstamps

NYTimes_Foodstamps_Change

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On interest rates

In what Tyler Cowen calls “Critically important stuff and two of the best recent economics blog posts, in some time,” Paul Krugman and Brad DeLong have got some interesting thoughts on US interest rates.  First Krugman:

On the face of it, there’s no reason to be worried about interest rates on US debt. Despite large deficits, the Federal government is able to borrow cheaply, at rates that are up from the early post-Lehman period … but well below the pre-crisis levels:

DESCRIPTION

Underlying these low rates is, in turn, the fact that overall borrowing by the nonfinancial sector hasn’t risen: the surge in government borrowing has in fact, less than offset a plunge in private borrowing.

So what’s the problem?

Well, what I hear is that officials don’t trust the demand for long-term government debt, because they see it as driven by a “carry trade”: financial players borrowing cheap money short-term, and using it to buy long-term bonds. They fear that the whole thing could evaporate if long-term rates start to rise, imposing capital losses on the people doing the carry trade; this could, they believe, drive rates way up, even though this possibility doesn’t seem to be priced in by the market.

What’s wrong with this picture?

First of all, what would things look like if the debt situation were perfectly OK? The answer, it seems to me, is that it would look just like what we’re seeing.

Bear in mind that the whole problem right now is that the private sector is hurting, it’s spooked, and it’s looking for safety. So it’s piling into “cash”, which really means short-term debt. (Treasury bill rates briefly went negative yesterday). Meanwhile, the public sector is sustaining demand with deficit spending, financed by long-term debt. So someone has to be bridging the gap between the short-term assets the public wants to hold and the long-term debt the government wants to issue; call it a carry trade if you like, but it’s a normal and necessary thing.

Now, you could and should be worried if this thing looked like a great bubble — if long-term rates looked unreasonably low given the fundamentals. But do they? Long rates fluctuated between 4.5 and 5 percent in the mid-2000s, when the economy was driven by an unsustainable housing boom. Now we face the prospect of a prolonged period of near-zero short-term rates — I don’t see any reason for the Fed funds rate to rise for at least a year, and probably two — which should mean substantially lower long rates even if you expect yields eventually to rise back to 2005 levels. And if we’re facing a Japanese-type lost decade, which seems all too possible, long rates are in fact still unreasonably high.

Still, what about the possibility of a squeeze, in which rising rates for whatever reason produce a vicious circle of collapsing balance sheets among the carry traders, higher rates, and so on? Well, we’ve seen enough of that sort of thing not to dismiss the possibility. But if it does happen, it’s a financial system problem — not a deficit problem. It would basically be saying not that the government is borrowing too much, but that the people conveying funds from savers, who want short-term assets, to the government, which borrows long, are undercapitalized.

And the remedy should be financial, not fiscal. Have the Fed buy more long-term debt; or let the government issue more short-term debt. Whatever you do, don’t undermine recovery by calling off jobs creation.

The point is that it’s crazy to let the rescue of the economy be held hostage to what is, if it’s an issue at all, a technical matter of maturity mismatch. And again, it’s not clear that it even is an issue. What the worriers seem to regard as a danger sign — that supposedly awful carry trade — is exactly what you would expect to see even if fiscal policy were on a perfectly sustainable trajectory.

Then DeLong:

I am not sure Paul is correct when he says that the possible underlying problem is merely “a technical matter of maturity mismatch.” The long Treasury market is thinner than many people think: it is not completely implausible to argue that it is giving us the wrong read on what market expectations really are because long Treasuries right now are held by (a) price-insensitive actors like the PBoC and (b) highly-leveraged risk lovers borrowing at close to zero and collecting coupons as they try to pick up nickles in front of the steamroller. And to the extent that the prices at which businesses can borrow are set by a market that keys off the Treasury market, an unwinding of this “carry trade”–if it really exists–could produce bizarre outcomes.

Bear in mind that this whole story requires that the demand curve slope the wrong way for a while–that if the prices for Treasury bonds fall carry traders lose their shirts and exit the market, and so a small fall in Treasury bond prices turns into a crash until someone else steps in to hold the stock…

For reference, here are the time paths of interest rates for a variety of term lengths and risk profiles (all taken from FRED):

interest_rates_1monthinterest_rates_3monthsinterest_rates_30years

To my own mind, I’m somewhat inclined to agree with Krugman.  While I do believe that the carry trade is occurring, I suspect that it’s effects are mostly elsewhere, or at least that the carry trade is not being played particularly heavily in long-dated US government debt relative to other asset markets.

Notice that the AAA and BAA 30-year corporate rates are basically back to pre-crisis levels and that the premium they pay over 30-year government debt is also back to typical levels.  If the long-dated rates are being pushed down to pre-crisis levels solely by increased supply thanks to the carry trade, then we would surely expect the quantity of credit to also be at pre-crisis levels.  But new credit issuance is down relative to the pre-crisis period.  Since the price is largely unchanged, that means that both demand and supply of credit have shrunk – the supply from fear in the financial market pushing money to the short end of the curve and the demand from the fact that there’s been a recession.

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Changing the typesetting margins in Scientific Workplace

At least half of the LSE economics department uses Scientific Workplace, but an absurdly large fraction of all PDFs they produce have two-inch margins so they end up wasting half the page.

I finally got sufficiently annoyed to discover how to change it:

  1. Open a SW tex file
  2. Under the ‘Typeset’ menu, choose ‘Options and Packages…’
  3. Under the ‘Packages’ tab, add the ‘geometry’ package
  4. Under the ‘Typeset’ menu, choose ‘Preamble…’
  5. Add a line at the end specifying the margins.

For example:

\geometry{left=1in,right=1in,top=1in,bottom=1in}

Units of measurement available are listed on the webpage where I got this:  http://www.mackichan.com/index.html?techtalk/370.htm

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Approximating a demand function with shocks to the elasticity of demand

Entirely for my own reference …

A demand function commonly used in macroeconomics is the following, derived from a Dixit-Stiglitz aggregator and exhibiting a constant own-price elasticity of demand ($$\gamma$$):

$$!Q_{it}=\left(\frac{P_{it}}{P_{t}}\right)^{-\gamma}Q_{t}$$

A demand-side shock can then be modelled as a change in the elasticity of demand:

$$!Q_{it}=\left(\frac{P_{it}}{P_{t}}\right)^{-\gamma D_{t}}Q_{t}$$

Where $$\ln\left(D_{t}\right)$$ is, say, Normally distributed and plausibly autocorrelated.  We can rewrite this as a function of (natural) log deviations from long-run trends:

$$!Q_{it}=\overline{Q_{t}}e^{q_{t}-\gamma e^{d_{t}}\left(p_{it}-p_{t}\right)}$$

Where:

  • Variables with a bar above them are long-run trends:  $$\overline{X_{it}}$$
  • Lower-case variables are natural log deviations from their long run trends (so that for small deviations, they may be thought of as the percentage difference from trend):  $$x_{it}=\ln\left(X_{it}\right)-\ln\left(\overline{X_{it}}\right)$$
  • The long-run trend of all prices is to equal the aggregate price:  $$\overline{P_{it}}=\overline{P_{t}}$$
  • The long-run trend of $$D_{t}$$ is unity

We’ll construct a quadratic approximation around $$q_{t}=p_{it}=p_{t}=d_{t}=0$$ but, first, a table of partial derivatives for a more general function:

Function Value at $$x=y=z=0$$
$$f\left(x,y,z\right)=ae^{x+bye^{z}}$$ $$a$$
$$f_{x}\left(x,y,z\right)=ae^{x+bye^{z}}$$ $$a$$
$$f_{y}\left(x,y,z\right)=abe^{x+bye^{z}+z}$$ $$ab$$
$$f_{z}\left(x,y,z\right)=abye^{x+bye^{z}+z}$$ $$0$$
$$f_{xx}\left(x,y,z\right)=ae^{x+bye^{z}}$$ $$a$$
$$f_{yy}\left(x,y,z\right)=ab^{2}e^{x+bye^{z}+2z}$$ $$ab^{2}$$
$$f_{zz}\left(x,y,z\right)=abye^{x+bye^{z}+z}+ab^{2}y^{2}e^{x+bye^{z}+2z}$$ $$0$$
$$f_{xy}\left(x,y,z\right)=abe^{x+bye^{z}+z}$$ $$ab$$
$$f_{xz}\left(x,y,z\right)=abye^{x+bye^{z}+z}$$ $$0$$
$$f_{yz}\left(x,y,z\right)=abe^{x+bye^{z}+z}+ab^{2}ye^{x+bye^{z}+2z}$$ $$ab$$

So that in the vicinity of $$x=y=z=0$$, the function $$f\left(x,y,z\right)$$ is approximated by:

$$!f\left(x,y,z\right)\simeq a + a\left(x+by\right) + a\left[\frac{1}{2}\left(x+by\right)^{2}+byz\right]$$

From which we can infer that:

$$!Q_{it}\simeq \overline{Q_{t}}\left[1+\left(q_{t}-\gamma\left(p_{it}-p_{t}\right)\right) + \frac{1}{2}\left(q_{t}-\gamma\left(p_{it}-p_{t}\right)\right)^{2}-\gamma\left(p_{it}-p_{t}\right)d_{t}\right]$$

If introduced to a profit function, the first-order components ($$q_{t}-\gamma\left(p_{it}-p_{t}\right)$$) would vanish as individual prices will be optimal in the long run.

Update (20 Jan 2010): Added the half in each of the last equations.

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Gray markets, PPP and the iPhone in China

Via Felix Salmon, I found this fantastic piece by “Bento” on the take-up of the iPhone in China.

Some background:  When Apple launched the iPhone in China, early sales numbers were disappointing.

Some background to the background:  Under Chinese law, WIFI-enabled phones are illegal, so Apple has to cripple the iPhones they sell in China.

From Bento:

The Chinese have long had access to iPhones. They are for sale at stalls in every cybermall and market in every Chinese city, and come in two varieties: The most expensive ones (at around 6000 RMB in Shanghai for a 16GB 3GS, or 880 USD, depending on your haggling skills) come directly from Hong Kong, where the factory-unlocked model is available from the Apple store for around 4800 RMB. That’s a nice arbitrage play by the stall owner, and everyone is happy. The cheaper model, at around 5000 RMB for a 16GB 3GS, was originally bought locked in the US or Europe, and has been unlocked by the stall owner’s hacker-genius cousin using 3rd-party software. This kind of iPhone is cheaper, because you are on your own when it comes to upgrades and iTunes compatibility.

The distribution model is extensive and robust, and in fact most Chinese buy their mobile phones from stalls like this. There are no iPhone shortages, as prices fluctuate to meet demand. The received wisdom is that around 2 million iPhones are in the Chinese wild; I’ve personally seen a good many of them here in Shanghai, where they are much in evidence among the eliterati. Still, this is a minuscule portion of the 700 million odd phones in use in China, of which a small but growing portion is smartphones.

What can Apple do to grow the number of iPhones on mainland China? Short of lowering prices in Hong Kong (not going to happen) it can do two things: Increase awareness of the iPhone via advertising, and bring the benefits of a Chinese-language App Store to Chinese iPhone owners.

To do either of these, you sort of need to sell the product locally first, though. Apple can’t really go round putting up banners in Chinese tier-3 cities urging consumers to head for the local iPhone aftermarket.
[…]
Apple … is not revenue-sharing with China Unicom, the local vendor, but selling the iPhones outright to them. It is up to China Unicom to flog them in China.

And that’s what China Unicom is trying to do. China Unicom stores all have iPhone banners up; I’ve passed several China Unicom road shows stopping by Shanghai extolling the iPhone. The iPhone is being talked about widely. But so is the fact that the China Unicom iPhone is crippled — the Chinese are sophisticated consumers; forget this at your own peril.

The upshot: anecdotal reports tell of aftermarket prices increasing for Hong Kong iPhones these past few weeks, as demand increased. Clearly, the advertising is working, even if China Unicom’s sales of wifiless iPhones are anaemic.

Arbitrage is clearly still happening — buy for 4800 RMB in Hong Kong, sell for 6000 RMB in Shanghai; that’s a 25% markup and well above any reasonable estimate of transportation costs — so Purchasing Power Parity (PPP) doesn’t even hold within the “one” country, but this is a great example of gray market imports.