Best of 2011

Time for some intense naval-gazing. I wasn't going to do one of these, but then I enjoyed others' so much for the posts I missed that it seemed much more interesting.

Top Ten Posts of 2011
1. Google's statement on AUN's amazing internet usage, got a lot of doubting comments and a few  defending and very plausible explanations.
2. Nutrition Labeling, describing the new requirement that meat include information on calories from fat.
3. Unemployment: Leads and Lags - Breaking unemployment into separate decisions to hire or fire will give us a better indicator of where the economy is going (has been) than total unemployment.
4. AEA session on agricultural export bans during the 07/08 food price crisis.
5. Microinsurance in Kenya via cellphone
6. My first visit to AUN. Classes will resume Thursday the 24th
7. Low saturated fat diet vs. low simple carbohydrate diet
8. QE2 and food prices - debunking the idea that the Fed is causing global food price inflation
9. Food safety, food movements, and paternalism
10. Lit in Review: Food Demand -- Ethiopia and Speculators
Honorable Mention (because I thought it was fun): The socially acceptable price of fried chicken, also known as the political economy of fast food markets in South Korea.

Top Ten Posts of 2010 (in 2011)

1. My pictures of the Thorvaldsen's Christus and apostles statues, mentioned in a Church lesson this year.
2. Lit in Review: Grossman and Helpman, there has been steady interest in summaries and other papers that make use of the "Pay to Play" model of lobbyists.
3. Food in Africa: Too much and too little discussing the problem of getting food from food-surplus states to food-deficit states. There was never a large spike, but a steady stream of interest throughout the year.
4. High Hopes for Rwandan Agricultural Development
5. Food Security in Nepal which has been of increasing interest lately
6. Cutting Costs Through ... Fonts?? Some fonts go easier on the printer's ink
7. Population Health vs. Individual Health - commentary on macro vs. micro in economics and health
8. Ethiopian Monetary Policy - combines monetary policy, food prices, Ethiopia's development goals (food self-sufficiency), and growth prospects
8. Five from vacation: education, hyperinflation, and Chinese food safety.
10. Fed governor: if we could guarantee 5% NGDP growth, it would be great - I'm glad this made the list because I think it was my most significant post, interviewing Governor Dudley about what they are targeting and Sumner's policy.

Where did my visitors come from in 2011?

The Lighter Side of ... Development, Drinks, and Demonized Demonstrators

Dear Mr Gandhi: We regret we cannot fund your proposal because the link between spinning cloth and the fall of the British Empire was not clear to us.

Claims about our food

The health claims made by potato chip manufacturers apparently vary with the price. Most popular are reminding people what's NOT in the bag: every negative increases the cost by 4 cents per ounce. Expensive chips are much more likely to have any health claim than cheap chips, which tend to emphasize being locally made.

Sugar says that using the term "corn sugar" misleads consumers by claiming that "HFCS is natural and is indistinguishable from the sugar extracted from sugar cane and sugar beets." Corn says sugar is misleading consumers by "wrongfully alleging that high fructose corn syrup (a sugar made from corn) causes health issues that do not arise from consuming cane and beet sugar." While the journalist reporting on this does manage to get M. Nestle (way down at the bottom) to comment, we also get a quote from an "alternative medicine guru and author" ... What? All the real doctors were busy?

Speaking of sugar, how much is in kids' cereals? M. Nestle reports on an Environmental Working Group report:

kids’ cereals are really cookies in disguise, typically 40% -50% sugars by weight.   Kellogg’s Honey Smacks topped the list at 55%. ... 

The good news is that at least some cereals are managing to reduce sugar content. (Image source: General Mills)


 There is a claim that Wendy's may soon be the #2 burger establishment, unseating the Burger ... well, he can't be king since he's #2 and about to be #3, how about the Burger Prince then? I have appreciated seeing Wendy's posting calorie counts in some states that don't require them and have adapted my own consumer choices accordingly. Just don't go to the Wendy's in Ithaca - I got food poisoning there twice. Update: On Wendy's triumphant return to Japan.


Carl's Jr's chief, meanwhile claims the Affordable Care Act will be bad for business because it will increase the costs of doing business. His argument makes it sound as if this is a fixed cost - the company will just have to shell out an extra $18 mil each year. Actually, they are variable costs that depend on how many people they choose to employ. Making labor more expensive does discourage building more stores as he says on an income effect, but there is a substitution effect that tells them to use more machines and fewer people, or more temps who can be excluded from the Act. Yglesias points out that much more relevant are the requirements that say restaurants like Carl's Jr will need to post calorie and other nutrition information, which will likely have an even larger impact than the employment costs.

Food policy sausage

Where does Indian agricultural policy come from? IFPRI has a new report out on how the subsidy sausage gets made, and in particular what is keeping them from making better policy.

This study throws new light on the factors that have so far prevented a move toward more pro-poor and environmentally sustainable agricultural input policies in India. The authors show that electoral politics, institutional factors, and policy paradigms or belief systems all play an important role in blocking reform.

Where did the idea of people consuming 2000 calories a day come from? M. Nestle answers from her forthcoming book: a survey + marketing. Reality is complex, with surveyed responses varying over 1400 calories per day just in what Americans admitted to eating, let alone what was actually consumed. 2000 is easy to remember, easy to divide, and less than they were recommending for most real people so as not to give an appearance of over-encouraging saturated fat and salt. But as to how many calories you personally should actually consume to be healthy and satisfied, even she gives little real help: if you're gaining weight, you're eating too much.


How is it that farmers' market food safety regulation comes out so differently from that for corporations? Tucker discovers there are (at least) two kinds of farmers' markets and points out the idiosyncracies and food safety problems in our governance of them. Attending the university-sponsored one on a whim, he found the upscale farmers market with prices to match. In another town, the market was "kept alive by the workers and peasants. The price were 1/3 to 1/2 as much as the local grocery. They have locally grown produce, and a fantastic cart full of virtually free produce that is about to spoil." He notes that neither one was easily a pure exercise in local food. At the second, he bought Vietnamese fish. At the first:

For example, the man with super-cool rabbit meat, lamb and goat sausage, and the like, had come 3.5 hours, and he does this every week, even though he doesn’t have a refrigerated truck. Every corporate giant faces a labyrinth of inspections and mandates comparable to the Soviet Gosplan, just to get meat to the market. And yet here is a guy with some animals on his land who slaughters, grinds, packs, and sells, and no one seems to be bothering him. No inspectors, no special tests, no mandates. Puzzling. Thrilling but puzzling.

Food Stamps and Soda in 3 Acts

The political economy of soda, part 1, NYT via M. Nestle

Eighteen members of the Congressional Black Caucus recently urged the Obama administration to reject New York’s proposal. The plan is unfair to food stamp recipients because it treats them differently from other customers, they said in a letter to Agriculture Secretary Tom Vilsack.
While Coca-Cola and PepsiCo are among the largest contributors to the nonpartisan Congressional Black Caucus Foundation, a research and education institute, caucus members say their positions are not influenced by such contributions.

Policy advice, Part 2 from Wilde:

1. You never should have called the proposed policy a ban. Has there ever been a controversy over the "ban" on SNAP spending for hula-hoops and yo-yos? The "ban" on SNAP spending for gasoline? No

Part 3 … is just funny.

Run-Of-The-Mill Requests

Gas station | Madison, WI, USA
(A customer sets all their items up on the counter. This includes a six-pack of beer.)
Me: “Okay, your total will be $12.12.”
(The customer hands me their food stamp card.)
Me: “I can run this through, and it’ll take most of the total off. But beer isn’t covered under this program. I apologize.”
Customer: “Excuse me, what?”
Me: “Yeah, alcohol isn’t covered under the Supplemental Nutritional Assistance program.”
Customer: “But beer is nutritional. It has wheat in it.”

Why Americans Got Fatter

The interactive chart is at Civileats (HT: Yglesias), but the snapshot is pretty informative:


On the left is what we ate in 1970.


On the right is what we ate in 2007.




The differences are: 200 calories of added fats, 200 calories of grains, 50 of added sugars, and 20 more calories each in meat and fruit. Getting rid of rounding, that’s more than 500 calories every day, or a pound a week. Now, granted, that’s available calories (production – trade – non-restaurant waste) rather than actual consumption. Still quite the picture
Almost half of that change happened between 1980-1990 and more than half since 1990. The real change I want to figure out is what happened in the data between 1999 and 2000. Between those two years we added 100 calories of added fat alone.

Five Second: Economist on the new food regime; Part 1

The Feb 24 edition of The Economist contained a special insert on the global food situation since the global food price crisis of 07/08. Here are some of the highlights:

On the potential for improving agricultural productivity in Africa: “Given the same technology, European and American farmers get the same results.”

On obesity they aren't quite right: “Food is probably the biggest single influence on people’s health, though in radically different ways in poor countries and in rich ones, where the big problem now is obesity. … In the favelas (slums) of São Paulo, the largest city in South America, takeaway pizza parlours are proliferating because many families, who often do not have proper kitchens, now order a pizza at home to celebrate special occasions.” Obesity has been and is growing rapidly in developing countries where sometimes within the same family you can find both hunger and obesity.

On nutrition vs. calories: “Feeding the world is not just about calories but nutrients, too; and it is not about scattering them far and wide but pinpointing the groups who can and will eat them.”

“In Tanzania, children whose mothers were given iodine capsules when pregnant stayed at school for four months longer than their siblings born when the mother did not get those capsules.” “Half of those over 75 in hospital are reckoned to be nutrient-deficient, as are many obese people.”

Fortification: “Better nutrition, in short, is not a matter of handing out diet sheets and expecting everyone to eat happily ever after. Rather, you have to try a range of things: education; supplements; fortifying processed foods with extra vitamins; breeding crops with extra nutrients in them. But the nutrients have to be in things people want to eat. Kraft, an American food manufacturer, made Biskuat, an “energy biscuit” with lots of extra vitamins and minerals, into a bestseller in Indonesia by charging the equivalent of just 5 cents a packet. It also did well in Latin America with Tang, a sweet powdered drink with added nutrients, marketing it to children for the taste and mothers for its nutritional value.”

Biofortification: “It is also possible to breed plants that contain more nutrients. An organisation called HarvestPlus recently introduced an orange sweet potato, containing more vitamin A than the native sort, in Uganda and Mozambique. It caught on and now commands a 10% price premium over the ordinary white variety. The local population’s vitamin intake has soared.”

If we produce enough calories to feed the world now, “why worry about producing more food? Part of the answer is prices. If output falls below demand, prices will tend to rise, even if “excess” calories are being produced. … Pushing up supplies may be easier than solving the distribution problems.”

The downside of Zero Tillage: “weeds. They like to grow in the mat as much as crops do.”

The Lighter Side: Humor

French kids mulling over what pieces of "ancient" technology might be. (HT: Yglesias)

Apparently Justice Scalia is the funniest person on the Supreme Court, though he is known for repeating jokes. Speaking of humorous SCOTUS decisions, in one timeline they decided that Superman was born in an artificial womb on US soil, so was eligible to run for President. Remember, "the case of Uatu v. Lewis (1993, supra) firmly established that counterfactual legal precedents are binding on lower courts until explicitly overruled by the Supreme Court."

I reported earlier on unusual incentives to get married in Haiti. In Cuba, the unusual incentive is to be able to move. It may be true that 85% of the population has a home, but that doesn't mean they are allowed to sell it. They can only trade homes for one of equivalent value with difficult-to-acquire state approval. Orrrr they can marry the owner of a better home, move the deed to their name, and then divorce.

Another response to the Chinese mother article:

If you're Asian American -- or if you have close Asian friends -- you know that a staple of Asian American humor is stories about over-the-top maternal expectations and demands. Black folks tell "yo momma" jokes; Asian folks tell "my momma" jokes.

 Yes, we really do know that fast food is always bad for us ... just not always?

Me: “Welcome to our store, would you like to try out fruit oatmeal today?”
Customer: “Wait, that actually sounds healthy. I’m confused.”

While sentences like this "my goal for 2011 is to fail more" and this "I have a ‘failure resume’" are not intended to be funny, humor is part of what helps us accept our failures and move forward with hope.

2011 -- Year of the ...

The promises of a tranquil Year of the Rabbit are nice, but unlikely in our household. The Lovely and Gracious and I learned yesterday that it will be a little girl that we will be welcoming this summer. In the spirit of celebrating the Chinese New Year, we recite to ourselves the marriage advice from the Chinese Zodiac that you marry someone 4 years younger or older than yourself, but never someone 6 years apart. (We happen to be 6 years apart and very happy together.)

But 2011 is not only the year of the rabbit. FAO has declared 2011 the Year of the Forest. The UN has also inaugurated the Year of Chemistry and the Year of Youth. Combining them would suggest we are celebrating the use of chemical fire retardant to fight youthful arsonists. Or maybe we're using homeopathic chemistry to make ourselves look younger.

Conservation groups declared last year the year of the shark. This time we get the Year of the Bat under the banner "Together with bats."

CNN has called for Latin America to celebrate the Year of the Female Politician with Brazil's first female President and several other notable state leaders from Costa Rica to Peru and beyond.

The Center for Consumer Freedom opines we may see The Year of the Nanny. "(Qualities: irritating, finger-wagging, spiteful, incapable of having a good time. Partners best with regulators. Incompatible with freedom and common sense.)" Then again, nearly every year is the year of the nanny to freedom-lovers because some dimension of freedom is constantly on the defensive. This year the theme seems to be food and obesity-related nannying.

The year 2011 will see the "M1C problem," similar to the Y2K bug, but only in Taiwan which dates this as year 100. The Australian of the Year for 2011 is a social entrepreneur who encourages philanthropy for international development.

All of this is assuming that 2011 is not, in fact, the Year of the Zombie Apocalypse. My favorite post on Zombie Politics.

Yes, We Know Fast Food is Bad for Us

I've mentioned the San Fransisco law to ban toys in fast food before. The Daily Show did a great job with it.
Best moment: interviewing one of the law's proponents who admitted that the city does not have the authority to order a private company (e.g. Netflix) to change its business practices ... when that's exactly what they are doing to private companies. The fellow goes speechless for a second. Classic. Video below the fold.

Also (pictured) how to find real food at the supermarket a la M. Nestle.

Pictures that show the difference between the way food looks when advertised and when you actually buy it.

How to check to make sure your pizza is salmonella free.

Newmark presents one of the more interesting predictions for the future:

The U.K.'s Guardian assembles some experts to predict. Some are plausible; some are not. This one, from an executive at Ogilvy and Mather, made me laugh:

In 25 years, I bet there'll be many products we'll be allowed to buy but not see advertised – the things the government will decide we shouldn't be consuming because of their impact on healthcare costs or the environment but that they can't muster the political will to ban outright. So, we'll end up with all sorts of products in plain packaging with the product name in a generic typeface – as the government is currently discussing for cigarettes.

(The man knows how government works.)

And while we're at it, some tongue in cheek celebrations of farmers' markets (also below the fold)

Big Bag of Monday

The last several weeks I have been concentrating on finishing the last proofs for our textbook, getting out job applications, and overcoming a Thanksgiving-week stomach flu so that despite increasing work hours 50%, the something that gives is what - let's face it - matters less: this blog. So without even worrying about catching up, this week will just feature some links to other people's interesting thoughts and I'll leave it at that.

Yglesias on TSA: But don’t ask yourself “what amount of hassle and expenditure is worth paying to prevent terrorist attacks,” ask yourself “what amount of hassle and expenditure is worth paying to shift terrorist attacks off airplanes and onto buses”? Much of the resources currently spent on “security” measures would be much better spent on having more police officers.

Wronging Rights on rethinking areas of state failure: I'm struggling to think of any country in history where the police haven't ever effectively ceded large chunks of territory to violent criminal gangs. (Frankly, the list of places where they aren't doing that at the moment is pretty short.) ... In wealthy, developed countries, we expect the police to enforce laws, investigate crimes, and come when someone calls for help. But in places without the rule of law - where the state doesn't have a monopoly on violence, and the state's use of violence isn't constrained by law - that's just not the role they play. There, the police are just another group that uses violence on behalf of the powerful.

Sumner on the monetary union: I get frustrated when I read people arguing the Eurozone problem is that the ECB can’t come up with a one-size-fits-all policy stance.  ... Actually money is even tighter in Europe than in the US.  It’s too tight for every single Eurozone member.   Nominal GDP is well below the levels of early 2008.

Marron notes that housing price decreases make core inflation look lower than it would otherwise ... but it's still respectably low at 1.3% if you take housing out. It's just not as spectacularly low. As I argued earlier, the question is what kind of inflation we are worried about. Changes in food, fuel, and housing prices are important for human welfare, but are not necessarily indicative of the effects of  Federal Reserve engineered increases in the money supply.

Marron on business uncertainty in Afghanistan being a greater concern for businessmen than physical uncertainty.

Cafe Hayek on the double imported "all-American" turkey's Mexican heritage. Speaking of animals, The Economist notes that pets and non-livestock near humans have been growing heavier and more obese over the last several decades as well.

APPAM Panel: Food insecurity

Wagle (W. Michigan) -- Food stamps increase recipient incomes. Food stamps also reduce work hours supplied by families. Given that, food stamps tend to increase the likelihood of families being poor while increasing incomes. It may help non-poor families more than poor families.   "The role of FSP on food and economic security cannot be over-estimated."
Mandell (UMBC) -- "Fuzzy" regression discontinuity to estimate SNAP on food insecurity and obesity -- Virtually no one above the cut off uses SNAP, contrary to Wagle's findings. Most estimates show SNAP increasing food insecurity, with no effect on obesity.

Discussant 2 (Tufts) -- The time to consider good instrumental variables is while USDA et al are preparing their surveys. Not "what do we happen to have that could do," but "what could we create that would tell us what we want"?

From my question: Eligibility for food stamps is based on all related people living in the household, but you can report income separately for younger individuals. You can therefore have data points where a "1-member-household" has an income too high for eligibility, but the larger family unit living together does qualify. There are a lot of data points also well above the maximum benefit. Most believe that is reporting error.

Q -- At the external margin, above the income cutoff makes you eligible for a little bit of food stamp which is easier to funge as a family, so regression discontinuity may not actually get you what you're looking for. An alternate interpretation is that it's a measure of selection pattern rather than the effect of just a little bit of food stamp.

Great recommendation: look at the selection effect of people leaving SNAP instead of entering.

Discussion of the other paper on teenage pregnancy below the fold.

Population Health vs. Individual Health

The nutrition and development economics I study have never been more interesting to my stomach. Food safety, improved water and sanitation services, the dangers faced by people with HIV/AIDS, and the drawbacks and difficulties of best nutrition advice come to the fore, not to mention the importance of health care services and the insurance helping to pay for it all. What I also conclude is that policies are built on population recommendations, but population-based science is inappropriate -- in my case regularly inappropriate -- for individual diagnosis.

The stresses of being on the job market and work have been upsetting my stomach. While doing some routine sample tests, my doctor discovered a parasite - cryptosporidium - was lurking. His best guess is that the parasite has been dormant and could have been in there for quite some time. Antibiotics should have cleared him out by now (can I just mention how thankful I am that I don't have to pass an "organic" inspection?). If I had HIV, it could have been a deadly infection.

You usually get cryptosporidium from drinking contaminated water, but it can readily be spread from one carrier through the food system and through public swimming pools. A fellow from the NY State health department called up to make sure I was not in a position to be spreading this around. We have not been able to identify when the infection may have occurred. I'm more thankful than ever for the efforts I've reported on in the past to bring improved water sources to people who don't have them. I'm also rather thankful to have a society with someone in it checking up on people like me to try to minimize the spread of these things.

Irritable bowel syndrome isn't the only option on the table, however, and that's what gets me into the policy arena...

Spin vs. Science: Fast Food Toys

Parsons over at Change.org has been cheerleading a San Francisco measure to ban giving away toys with fast food. The hope is that doing so will reduce obesity both currently (by reducing demand for fast food) and in the future (toys, it is hypothesized, make fast food more addictive and habit-forming). Since then, the San Francisco's Board of Supervisors' Land Use Committee has approved the measure, which will now go before the full board for final approval.

Parsons spins a few things in her favor in the process. She misquotes an op-ed which itself distorts the science it cites (Chou, Rashad, and Grossman, 2008, Journal of Economics and Law). The study compares children in 1979 and in 1997 (NLSY) using variation in the time spent watching fast food commercials to account for obesity. The data on fast food ads excludes national advertising (no variation), relying instead on metropolitan area codes; data on 1979 3-11 year old television watching comes from mothers while data on 1997 adolescent television watching is self-reported. Pairing those together provides the estimate of the amount of time spent watching fast food commercials. When BMI is the dependent variable, the estimate of advertising's effect is always positive, but is statistically significant only 2/12 times. The results on the probability of being overweight are somewhat stronger statistically, but this explains only 10% of the variation.  It seems rather strong to claim -- as Parsons and to a lesser extent the authors -- that we could reduce child obesity by 18% by banning something that explains 10% of the variation.

There is no simple direct obvious causation statement that can or ought be made from the research, though Parsons has. CRG cite, for example, the Institute of Medicine arguing that "the final link that would definitively prove that children had become fatter by watching food commercials aimed at them cannot be made." CRG admit that "Clearly, our estimate of the probability that a given child saw a certain message is subject to error" and that "As indicated in Section 1, there is conflicting evidence on trends in television and commercial viewing by children and youths since 1980. Hence, it would be premature to point to our findings as a partial explanation of the upward trend in obesity."

The conclusion of the study puts more conditionalities into the discussion:

What Americans Eat in a Year

Graphic here. We eat 2000 pounds of food each year, or 2700 calories per day.

• A gallon per week of soda. I drink well more than that, but only diet soda.
• Almost a pound per week of corn syrup, almost 3 pounds of caloric sweeteners, and a pound and a half of oils and fats.
• Half a pound a week each of french fries, pizza, ice cream, and non-caloric sweeteners
• 250 mg of caffeine per day, the equivalent of:
• 26 oz of Starbuck's Grande Latte or Red Bull
• 60 oz of Diet Coke or....
• 400 oz of chocolate milk

Subsidies and Nutrition: an upcoming study

Change.org reports and tries to get at the, well, one root of the problem:

In a 15-month experiment, a new federal initiative will offer some Massachusetts food stamps recipients a discount on fresh fruits and vegetables.... Beginning next fall, several thousand participants in the food stamp program, or Supplemental Nutrition Assistance Program (SNAP), living in Western Massachusetts will receive 30 cents off each dollar spent on fresh produce. The plan is part of a $20 million initiative outlined in the U.S. Department of Agriculture's (USDA) 2008 Farm Bill. Researchers will track shoppers' habits, controlling for other factors including income, race, and age, according to the Boston Globe....
Junk foods aren't actually cheap; our government just pays for them at the growing end in the form of enormous subsidies to large farms. The USDA spent $15 billion in subsidies to peanut, cotton, wheat, rice and corn farmers last year alone and spent less than one percent on produce farmers (the USDA recently announced it will stop reporting its subsidy data.)

What both of them are missing are the previous research on income and substitution effects.

Banning Harry Potter to Reduce Obesity

A proposed San Francisco law (done in other CA cities) wants to outlaw giving away a toy (like Harry Potter figures) with food that has too many calories, fat, salt, or sugar. In other words, take the happy out of the happy meal because it may condition children to unhealthy eating.

The proposed law not only bans restaurants from including toys with unhealthy meals, it stipulates that entrees must come with fruits and vegetables in order to offer a toy. Junk food purveyors use kid-friendly characters for evil, but there's no reason these same characters can't incentivize healthy eating. In many cases, youngsters want Chicken McNuggets and an order of fries because that meal comes with a shiny, new Hot Wheels car. If that same car came with, say, a grilled chicken sandwich, apple slices, and sauteed asparagus, kids could have their toy and eat healthy meals, too.

1 - Grilled chicken, probably. Apple slices, definitely. Asparagus? Who are you trying to fool?

2 - A less invasive law would stipulate that, if you choose to give a toy with a meal, you need to give it with healthy foods as well. That preserves greater freedom of choice and still accomplishes most of whatever minuscule, secondary effect this has on obesity.

3 - Is there any way to separate kids' choices from parents' choices in this discussion? If any other options are available, you don't go to fast food in order to get something healthy (though I appreciate and order less-bad-for-me alternatives), and it's the parents who choose to go to MickeyDs or whoever. ... On the other hand, I do recall whiningly encouraging my parents to Pleeeeeeeeeeeeease stop at Arby's to try to complete my collection of silly characters they had.

My general rule of thumb professionally is to answer the secondary question: Assuming we go ahead with something like this, is there a better way to do it? This is what points 2 and 3 discuss. There is though the broader question of if this is really a public good we're talking about and if the government should be involved at all. My kneejerk reaction says this will have almost no effect and shouldn't be done on those grounds alone. My two other hands (or knees?) point out that (1) the freedom being infringed on - the freedom to sell or buy a cheap toy with less nutrition food - is really quite minor compared to the culture of infringement we have so that those opposed have bigger breaded fish to deep fry; and (2) this is a local matter and locals and states are given very wide latitudes in our Constitution. Part of it being a local matter is trusting that San Fransiscans can decide for themselves what policies they want without some Cornell post doc trying to butt in. ...

And that's why I developed my rule of thumb! Okay, so you want to do this, how could you get equivalent results better? Allow more substitutions so parents can enforce healthier choices than children are liable to make. Kids won't ask for the salad, but parents may. It preserves more choice.

Five Second ... DiNardo: What is causality?

One of the best things I pulled out of my stack of reading last month was the third part of DiNardo's review of Freakonomics, published in the Journal of Economic Literature, Dec 2007. This was less about what he had to say about the book as what he had to say about causality and randomized controlled trials (RCTs). It's an excellent instructional piece to get students thinking about correlation vs. causality. Some of his better points are in the footnotes [which is also where I finally found a professional picture of him. His website features pictures of DiNardos he is not]. A smattering of the points he makes:

"Rather than hold up the RCT as a paradigm for all research, I review it here because it represents a single case in which we sometimes have some hope of evaluating (limited, context dependent) causal claims, and because what constitutes a severe test is somewhat clearer. ... The RCT often provides a useful template to evaluate whether the causal question is answerable. ...

"For any individual ... we can never be certain that some unobserved determinant of the outcome y is changing at the same time we are assigning the person to treatment or control."

Never. But there are uses.

• A doctor studied the 1590 siege of Paris. "He was led to conclude that one of the 'effects of insufficient food' was that the lethality of diseases such as typhoid was much greater. Nonetheless, 'hunger' or 'lack of food' was rarely cited as a 'cause' of death, although he identified undernutrition as an 'underlying potential cause.'"
• From Heckman (2005): "Two ingredients are central to any definition [of causality]: (a) a set of possible outcomes (counterfactuals) ... and (b) a manipulation where one (or more) of the 'factors' ... is changed." This is how we usually approach both RCTs and economics in general when we talk about regressions. Holding other factors constant, the effect of x is beta.
• Commenting on Moffitt (2005): "[The argument ... that race can not be a cause because it can not be manipulated results from] ... a mistaken application of the experimental analogy.... It does not make conceptual sense to imagine that, at any point in the lifetime of (say) an African-American, having experienced everything up to that time, her skin color were changed to white.... Although it is a well-defined question, it may nevertheless be unanswerable, and it may not even be the main question of interest...." DiNardo writes: "If I were to wake up tomorrow and discover that my skin color had changed dramatically, one possible reaction might be a visit to the Centers for Disease Control to learn if I had acquired an obscure disease! ... If that response were typical of other white folks who woke up one day to find themselves "black," I would nonetheless hesitate to say that the "causal effect of being black" (or white) is an increase in the probability that one makes a visit to the CDC."  Brilliant.

His discussion of obesity is quite illuminating. It seems a shame to paraphrase it but it's a touch long. The key question is how the weight is added or dropped. If weight is lost by starvation, mortality and other disease incidence may increase, suggesting that obesity causes good health. Further, different people have different ideal weights and it may be that lowering one's weight too much is in fact unhealthy. "The presumption that obesity is a cause of ill health made it virtually impossible to debate whether nonobesity was the cause of the increased heart problems." In fact, Gronniger (2003) finds that some income groups are benefited by being heavier. Thus, the salient policy question according to Gronniger "is not what obesity does to people, but what removing obesity would do to people" or, according to DiNardo identifying "the effect of Reddux or exercise."

What is Public Health and Why?

Marion Nestle's explanation (bold added):

public health makes it easier for individuals to make healthful food choices for themselves and their families. Or to put it another way, public health makes better food choices the default.

The classic example of a public health intervention is water chlorination.  As individuals, we could all boil our own drinking water to kill harmful organisms but this requires us to have stoves, pots, and fuel, and to know how to boil water.  For many people, having to do this would be an intolerable burden and responsibility.  Instead, some societies choose to take public health measures to ensure that drinking water is safe at the tap for everyone.
Other food examples: milk Pasteurization, banning of trans fats, food labeling. ...

Preventing obesity is another example: We could, as a society, take measures to make it easier for people to eat more healthfully and be more active (public health) or leave it up to individuals to do this for themselves (personal responsibility). Many of the arguments about suggested public health measures to prevent obesity are about how best to balance society’s needs with individual rights.  But as I see it, the proposals aim to tweak societal choices that have already been made: which crops receive farm subsidies, for example.... 

Obviously, both public health and individual approaches are necessary, but the overall objective of public health is to make it much, much easier for individuals to make better health choices without having to think about them. Because public health applies to everyone, it is essentially democratic.   And that’s one of the reasons why I think it matters so much.

Questions for Kagan

George Will is in the house and Newmark's at the Door:

If Congress decides interstate commerce is substantially affected by the costs of obesity, may Congress require obese people to purchase participation in programs such as Weight Watchers? If not, why not? . . .
If Congress concludes that ignorance has a substantial impact on interstate commerce, can it constitutionally require students to do three hours of homework nightly? If not, why not?
Can you name a human endeavor that Congress cannot regulate on the pretense that the endeavor affects interstate commerce? If courts reflexively defer to that congressional pretense, in what sense do we have limited government?

Should proper respect for precedent prevent the court from reversing Kelo? If so, was the court wrong to undo Plessy v. Ferguson's 1896 ruling that segregating the races with "separate but equal" facilities is constitutional?