Any outsider who’s visited rural Africa knows that outsiders, especially white folks, are fairly rare in those parts. As I’ve written before, I’m the object of curious stares and the subject of ridiculous rumors whenever I venture out into the set of villages that comprise my catchment area. It’s no surprise, then, that my presence might have an effect on how people respond to my survey.

Data is not the plural of anecdote, however – we need an actual, rigorous study to know that the presence of white folks matters, and especially to measure how exactly people’s behavior changes. What do they do differently? By how much? Jacobus Cilliers of CSAE describes exactly what is needed to answer those questions – along with Oeindrila Dube and Bilal Siddiqi he randomly assigned either a white person or a black person to sit in on an interview. The black person was in fact Sierra Leonese (the experiment was in Sierra Leone), but this experimental person didn’t talk, so that was really up to the subjects to infer from the person’s appearance – as was the presumable guess that the white person was a foreigner and probably British. In the interviews the subjects played the ever-popular dictator game, where one person is given a certain amount of cash and allowed to decide what portion to give to another person. They found that Sierra Leonese people are more generous in the presence of a white person than when all the researchers are black – to the tune of a 20% increase in giving to the other player in the games.

This is a cool idea, and really valuable research – we need to measure these kinds of effects so that we can assess the external validity of our research. Just because we’ve done a valid study for the population and setting chosen doesn’t mean that the results will carry over to the case where, for example, the white NGO representatives aren’t around. But I disagree with some of Jacobus’s advice on what to do to mitigate these outsider effects:

First, your presence in the research significantly undermines the results. You should either be absent when games and surveys are conducted, or randomly vary your presence. The success of impact evaluations could thus be overstated, if respondents “give the right answers” to please the researcher. Moreover, true behavioural change could be short-lived if it is determined by the presence of a “white man”, rather than the actual project.

Let’s start with the last part – our the results of impact evaluations overstated if, say, a white guy, is, for example, sitting in the project minibus writing blog posts while the surveys and interventions are going on? No. Remember that a valid impact evaluation involves randomization – participants are assigned to the treatment or control group strictly by chance, and therefore in expectation differ only in terms of whether they receive the treatment. The results of impact evaluations would be overstated only in the case where outsider effects *only* apply to members of the treatment group. There’s no reason to think that should be true.

Indeed, outsider effects are more likely to attenuate the measured results of an impact evaluation. Suppose that my being around makes people want to appear to be good citizens, and to underreport risky sex – that is, to lie. In the extreme, everyone reports no risky sex at all. If I use self-reported risky sex as my outcome, then I would find no effect of my intervention at all, even if it’s actually working.

What about the first point – does our presence significantly undermine the results of our research? The best we can say is “maybe”. The Cilliers et al. paper is a great first step, but the underlying research project was the dictator game, which is not itself an experiment. If you want to know if impact evaluation results are undermined by an outsider’s presence, you need to do a real RCT of some kind with a treatment and control group, and then do a cross-cutting randomization of whether outsiders are present. This is effectively two RCTs, which can be validly compared – one with with folks around and one without. Then you could see whether the measured effects differ between the variants of the study. Inasmuch as our presence does undermine the results, though, the effect is not to overstate the impact of a given intervention, but to understate it. So maybe we don’t care – lower bounds are very useful for discussing cost-effectiveness.

Now, what can we do about this? I totally agree with one of Cilliers’s suggestions – the best data is likely to come from not being around at all. The other option – to randomly vary one’s presence – is a very bad suggestion. First off, it’s not necessary – if the white guy is around for every village in the sample, then he has no differential effect across the treatment and control groups, and the results remain internally valid. Second, because the white guy’s presence has an effect on the results, randomly varying his presence may decrease the precision of any estimated effects. If the white guy’s presence is random, it will have on average the same effect for the treatment and control groups, so the experiment will remain valid. However, this additional random variation cpuld increase the residual variance of the outcome measure, which is bad for precision. Imagine that your outcome is unprotected sex, and everyone actually has unprotected sex 7 times a week if left to their own devices. The treatment causes them to decrease this to 4 times a week. However, the effect of the azungu being around is to cause everyone to shade down their risk-taking by 3 times per week – reporting 4 times and 1 time respectively. Then you estimate the same treatment effect whether the white guy is always around, never around, or around at random – it doesn’t matter if he’s there, as long as his presence is uncorrelated with the treatment. But the standard errors of the estimated effects are much larger if his presence varies randomly.

To see why, notice that we could replace the white guy actually showing up with a coin flip that randomly decreases people’s answers by 3. “Whitey never around” is a coin with tails on both sides – no answers change. “Whitey always around” is a coin that’s heads on both sides – all the answers change. This is fine! I could take your experimental data and add/subtract any number to all the observations, and the results would be unchanged; the difference between the treatment and control means would be the same. What about the “whitey randomly around” case? That’s a regular coins, one heads side and one tails side. I am literally adding random noise to the experimental data. That’s going to make my measurements less precise, and decrease my statistical power. Now, we can control for this since we know where whitey showed up – but even if we do, it gains us little. It’s also another thing to explain in our analysis. Randomizing whether the white guy is around is not a great idea – unless the goal is to measure the effect of the white guy on the results.

More broadly, let’s not forget that white guy* effects are only one variant of outsider effect. Irrespective of my presence, any survey project in rural africa necessarily involves the arrival of the following novelties in a village: 1) a car – kids love staring at and playing with it; 2) a bunch of folks from other villages, all at once and really well-dressed; 3) a bunch of compensation payments; and 4) people asking about all kinds of weird stuff like sex, whether you can read, and your income. Nothing we can do will eliminate any possible influence this stuff has on our results.

Hat tip: Development Impact

*I’m happy with framing this as being about white men, since, well, that’s me. But development as a field is predominantly female, especially outside of economics, and there are plenty of non-white outsiders working as researchers, NGO employees, and so forth.

I feel it’s necessary to begin here by noting that I have close to zero doubt that climate change is a real thing that will cause real problems in the future, and that we need to take strong and immediate actions (a carbon tax! or maybe cap-and-trade, whichever is more feasible) to do something about it. The fact that I feel the need to say that speaks to the strange position of science in American public life – whether you believe in climate change is a litmus test for what kind of person you are. My position marks me as someone who is pro-gay rights, pro-abortion, and more concerned about universal healthcare than about the federal budget deficit. This is pretty bizarre. It doesn’t seem appropriate to talk about whether you “believe” or “don’t believe” in a particular scientific fact. Do you believe in the precession of the perihelion of Mercury? What about the high likelihood that in a few billion years our sun will become a red giant and destroy the Earth? Or that bees can see in the UV spectrum? The correct answer is that these things are either true or false, and that we can look to the consensus of scientific experts to figure out which is the case. I don’t really get how it makes sense for random laypeople to have strong opinions about facts.

With the odd preamble out of the way, I recently was at a party where I was lucky enough to meet Stephen Carr, a renowned agriculturalist and author and general badass. I had heard of him beforehand (many people have recommended his book, Surprised by Laughter, which is currently on my to-do list), but couldn’t place him until after I had gone home. But as he told me a bit about his background, I started asking him about drought, rainfall and harvests in TA Mwambo, since I spend all day looking at the fields and trees out there and pondering how badly-off the kids are.

Carr made a couple of compelling points. First, he argued, Malawi has a high degree of natural variation in rainfall. There are years when the rains last a really long time, and years when they end early. There is also long-term variation – Lake Chilwa dried up very frequently in the first half of the 20th century, and since then has only done so twice. We can see the evidence for these long-term fluctuations in the level of Lake Malawi; because it has no inflowing rivers, its level reflects rainfall in its catchment area, and so is a good proxy for Malawi’s overall rainfall. Malawi is incidentally in the midst of a very wet period, compared to its historical mean.

He pointed out that all these variations have been happening for a long time, and that it’s totally wrong to ascribe for example the drop in the level of Lake Chilwa to climate change. The problem is that people do make just that connection, all the time. My response was basically “who cares?” – sure, people need to spin their issue to fit the sexy issue of the day in order to get money from donors. That’s been going on forever. But, as Carr pointed out, the spin matters. He noted that a couple of years ago the rains stopped before March*, and the government declared this to be climate change. They took this to mean that it would be a permanent problem, and told everyone to switch to early-maturing maize varieties. Fortunately, nobody listens to this kind of pronouncement and so very few people lost their harvests the next year, when the rains carried on strong through March.

Climate change will cause problems for Malawi – it’s going to make it even hotter here in the hot months, which won’t be good. But the hype around the issue in certain circles may have nasty consequences. This is another reason to push for a carbon tax, and not all these other miscellaneous programs to deal with the issue – the former will work, whereas most of the latter have no meaningful benefits and could do serious harm.

*I may have the precise details wrong here, I’m working from memory – any errors are my own and not Carr’s.

Another entry in my growing list of ways Malawi’s culture trumps what we do in the US. Malawian handshakes are always pretty cool – you start with a typical shake, then release and rotate your hand toward the person to grasp the back of their hand. It feels very legit, especially for a white guy (cool handshakes aren’t really our strong suit).

Cool handshakes are common in the US, though. Malawi really wins out when it comes to shaking hands when your hands are full. In America that leads to an awkward dance of shuffling crap between hands or trying to set stuff down. It is never cool, and usually embarassing for everyone. The Malawian solution is simple and elegant – if there’s stuff in your hands, you simply touch wrists. Moreover, this is a totally standard thing: no one thinks it’s weird or awkward or amusing, it’s just what you do, every time one party’s hands are full. This makes it fundamentally different and better than the American put-stuff-down tango, which feels like a failure and seems lesser than a real handshake.

One thing I try to keep in mind as I come with these ways in which Malawian culture is better than America’s is the feasibility of introducing the change. Usually changing a culture is pretty tough, if not impossible – they tend to evolve slowly due to powerful forces, not suddenly because we demand a change. This one seems really low cost, though. The tough part is getting everyone on the same page to begin with, so that no air of awkwardness builds up around the wrist-bump thing. That could undermine its main advantage.

The selection of Paul Ryan as the Republic vice presidential candidate has stirred up eternal arguments over America’s entitlement programs. This has in turn prompted the standard back-and-forth over whether Social Security constitutes a retirement account system, or is just another federal expenditure. Liberals (and I do consider myself one) tend to vehemently affirm the former and deny the latter. Here’s a recent-ish example from Noah Smith.

I’ve always found this strange – why are we even talking about the government’s unfundeded commitment to Social Security if it’s not a government expenditure? If it’s a system of retirement accounts, then once the federal government pays back what it has borrowed from those accounts, any obligation to pay for Social Security would be over with. At that point, if Social Security revenues (from payroll taxes) were less than its expenditures, it would go bankrupt. A bad outcome for people expecting benefits, but definitely not a fiscal catastrophe for the US. This is consistent with the law on Social Security – in Flemming v. Nestor, the Supreme Court ruled that you have no property rights over expected Social Security payments. Social Security is not savings – you do not own the funds in any legal sense. Congress can decide to stop paying you, or indeed all Social Security beneficiaries.

Now, I do understand what liberals are trying to do here. They think that they need to defend Social Security, and that people won’t like it as much if they think it’s a government program.* But it’s a really popular program – there’s no need for these rhetorical hijinks. I have my reservations about how the Social Security works, but it’s undeniably a vote-winner. Why trip over yourself about how it’s being framed?

And this isn’t a costless strategy. Framing Social Security as an retirement account system allows Republicans to carry on with one of the craziest lies in politics: the claim that over 50% of Americans pay no federal income taxes. That’s true if and only if we pretend that the payroll taxes that nominally fund Social Security and Medicare aren’t income taxes. But what are they, exactly? Are they your money? Yes. That gets taken away from you? Yeah. By the federal government? Yep. And are they mandatory? Totally non-optional. Does the money get spent on whatever the government wants, without regard to the name of the tax? Absolutely. They are taxes, but arguing that Social Security is a savings scheme lets Republicans pretend they aren’t and gain the advantage in the overall fight over entitlements. “See?” they say, “we’re in a death spiral of increasing numbers of listless, no-tax-paying leeches!” This is complete nonsense but since Democrats don’t want to talk about payroll taxes as taxes, no one ever heads it off.

It gets worse: payroll taxes are wildly regressive, too: they are 7.65%** of your income up to around $110,100, then that’s it, you don’t pay any additional payroll tax no matter how much you make. The savings account rhetoric leaves them out of the conversation when we discuss the equity of our tax code. It also means we can’t discuss unlinking benefits from income or removing the cap on payroll taxes, each of which could do a lot to make the Social Security system sustainable. To win a single, unimportant fight about what Social Security “really” is, Democrats have conceded almost the entire war over the size of government.

*Do they really believe the retirement account claim? I’m doubtful – most understand the reasoning above. And smart people all realize this is just quibbling over terminology. As a matter of practical policy, it doesn’t matter what Social Security “really” is.
**In reality they are 15.3% of your income. Half are nominally paid by the employer, but a basic analysis of tax incidence shows that who is supposedly charged the tax doesn’t matter – all that’s important is the relative elasticities of the labor supply and demand curves, and the total amount of the tax.

The shadow of an impending famine hangs over TA Mwambo. According to employees at AGORA and ADMARC, maize prices are reaching record heights on the back of a failed crop last year, and at present it is extremely dry. We’ve been teased by raindrops a couple of times, but they’ve never materialized into actual rain. Conversations about crops always take a detour through grumbling about a lack of action to do something about the impending situation.

Some of the obvious – and misleading – signs of famine in the popular are already here. In some villages half of the children have kwashiorkor; in others they all do. When I saw it, I looked up the causes to see if there’s anything I can do. It’s caused by protein deficiency, so simple multivitamins won’t do the trick. What’s more, although these kids are malnourished, none are wasting away. There’s food to be had, and it’s wrong to even say there isn’t protein. Every village we pass through has tons of livestock running around, and a large proportion of the men in Mwambo work as fishermen. I concede the possibility that the protein-deprived kids all belong to destitute families with no protein source, but a less savory explanation seems more likely: I suspect that many parents are making a choice – maybe a totally reasonable choice – not to give their kids enough protein to prevent kwashiorkor. That might be a way to pay for enough maize to feed the whole family, or it might be a way

What if famine really comes? First, to fix terms, I’m using “famine” in the colloquial sense (which is also the one used by Amartya Sen in his pathbreaking “Poverty and Famines”). It means mass death through starvation. Not a shortage of food, not a really bad shortage of food, not high food prices, not long queues for food. All of those are bad, but none are necessarily equivalent to famine. In the Malawian popular thought, there were famines in 2002 and 2005. From what I’ve heard, these were in fact food shortages – fairly terrifying ones – but I’ve found no evidence of widespread death in those years. In a paper I’m still working on, I have found evidence that the number of surviving children from those years is lower, but haven’t sorted out how much of that is infant mortality versus miscarriage versus delayed fertility. I don’t want to make like of what were no doubt horrible experiences, but as best I can tell there is a big gap between what happened here and for example last year’s famine in Somalia.

The central contribution of Sen’s book is to demonstrate that famines almost never involve a decline in the availability of food. In most cases, famine-struck regions actually export food to other areas. Instead, famines involve people being unable to afford the food they need to survive. Crop failures deprive them of the endowment of food/money they would normally use to survive, while also causing price shifts that make affording food impossible. This isn’t equivalent to the common idea that we have enough food but not the means to transport it to the needy. Mwambo sells tons of rice and maize and other crops which get bought by other Malawians. In a famine, that pattern would continue, using the high-quality tarmac road between Jali and Zomba town.

Many people have trouble believing that claim (that famines have nothing to do with food shortages), and it’s tough to get folks to read Sen’s book just to have their preconceived notions disproven. It’s a great book, which I do recommend highly (it’s pretty readabfle too), but I’ve often thought about how to convince people of its claims in a straightforward way. So here’s a thought experiment: if famine struck TA Mwambo while I was still here, do you think I would starve? Of course not. I would just buy food. Duh.

So if famine does arrive in Mwambo, god forbid, people will starve even while their neighbors sell food to people who live elsewhere in Malawi. If anything that is more horrific than the idea of there being no food around at all. But it also means there’s a simple solution: give people money. Not food, and certainly not surplus food from the US, which we’ve done in the past, but cash.

In the US, plumbing practicalities and limited space mean that we use our “bathroom” principally for eliminating waste; bathing is just a secondary use. Smarter folks than me have observed that, constraints aside, this is a pretty terrible arrangement: we intentionally go to the dirtiest room in the house the clean ourselves. God help you if you need to use the toilet before showering, the smell can be devastating.

A very different system obtains in rural Malawi. The toilet and the bath are generally different structures, separated by a fairly decent distance. Part of this is driven by necessity – pit toilets are disgusting – but part probably comes from the opportunity to rearrange two spaces that are outside the house anyway. The more urban the site, the less true this is – in places with running the water the two are often close together, or even combined in the standard Western style. Even in cities, though, at least having separate rooms is reasonably common.

Although I confess some benefits to the US arrangement – having one sink for both bathroom and toilet is nice, as is the shared storage – if I ever have the ability to design a house I’ll shoot for a toilet room that is separate from the bathing one.

I was forwarded a copy of John Mauldin’s latest “Thoughts from the Frontline” email column by a friend. It’s basically a finance/investing newsletter that centers on economic issues. I get this kind of thing sent to me fairly regularly, since people know I study economics. Sometimes (although not in this case) it’s also because folks expect someone with a masters in economics to know about investing, which couldn’t be farther from the truth. At best I can explain to you why you’re unlikely to beat a “diversify-and-hold” strategy, but I’m basically ignorant on that stuff. I’m going to go through this one in some detail, and then talk about this kind of “economic newsletter” more generally.

Mauldin makes bunch of claims, of various merits.

1) “How Are You Going to Keep Them Down on the Farm?” An economic history anecdote about the beginning of the shift from farming to the modern economy. This is interesting but I don’t see how it’s related to his other points. He alludes to something about graduate school, but what exactly is the grand shift he sees on the horizon? I may have missed that somehow.

2) “A College Degree Is Not Enough” It’s definitely true that a college degree doesn’t guarantee a job. It’s not clear whether it ever did, though – he doesn’t provide evidence on that point, and I can’t recall seeing this data in John Bound’s portion of second-semester graduate labor economics, which focused on human capital. (When I get back to Michigan I’ll ask him, I’m sure he knows). My thinking is you’d need to look at maybe the 1981 recession to see what happened “back in the day”. It’s also true that bachelors holders have a huge leg up over less-educated peers. Most of the talk about poor returns to education doesn’t pay enough attention to how badly-off high school graduates are.

3) “Boomers Are Breaking the Deal” The idea that boomers “breaking the deal” by working longer is a problem is a fallacy and directly contradicts his final point, about a shortage of workers to support retirees. There is not a finite supply of jobs in the economy. If there were, hundreds of millions of Americans would be out of work since we used to have far fewer total jobs than we currently have people. This idea (the “lump of labor fallacy”) is commonly cited but there’s no evidence that a larger workforce increases unemployment, except maybe over the very short term. Lots of evidence points out the opposite – developing countries (including the US in the past) uniformly undergo a “demographic dividend” where they have tons of workers and this drastically boosts their economies.

4) “Two Workers for Every Social Security Recipient” We definitely need more workers to sustain SS. One great solution is Mauldin’s third “problem” from above, which is that Boomers are working longer. This is great. It raises the size of the workforce while decreasing the number of retirees (People who are still working can collect some SS benefits, but not 100%, between age 62 and 67 (or so, the “full retirement age” depends on when you were born)).

After re-reading the newsletter, I’m not sure the points are supposed to be connected. But the ironic juxtaposition of his last two points.

With these emails, it’s important to consider the source, the audience, and the goal of the newsletter. Mauldin is a financial expert. While the newsletter disavows the idea that it’s selling anything, he is in the business of getting people to listen to him and (probably*) helping them invest. So there are three somewhat nefarious potential payoffs to doing this. One is attention – getting lots of people to read his newsletters is likely profitable, so it pays to be a bit sensationalistic and tell his audience what they want to hear. The second is the asymmetric returns to crazy predictions. In other such newsletters, it’s common to see forecasts of impending doom; circa January 2011 I was forwarded lots of assertions that we were about to experience hyper-inflation. No one is likely to remember your crazy predictions if they don’t pay off, but if they do, you get to be famous. The third is that you can make forecasts or conduct analyses that directly lead your readers to consume goods or services you’re selling. With the hyper-inflation talk, there was a lot of selling of gold and so forth.

I commend Mauldin for staying away from the second payoff, which can be tempting, but he’s definitely doing a bit of sensationalism and playing-to-his-audience bit. Investors lean Republican, so they like to hear stuff like the fact that one in eight American families are on food stamps or that one in two families get checks from the government. Neither are false, as far as I can tell, but both are overplayed – the second figure will rise mechanically as the population ages, for example.

As for directly profiting off the newsletter, I don’t see much of that either. He does market his talks at the bottom, so you could argue that his mild doomsaying is a way of encouraging attendance; if things are bad then you need to hear from the expert. I suspect this is more of a long game, though – he’s setting himself up as a reliable analyst for his target audience of rich, fiscally-conservative readers, so they will want to come to him for services in the future. This is the finance equivalent of a snack company sponsoring the paralympics.

Could this all be entirely ingenuous, just intended as thoughtful analysis on the economy? I’m doubtful, and my doubts return to the vast disconnect between his last two points. People trying to do thoughtful analysis for the public good usually impose a bit more consistency on their essays.

Hat Tip: Robert Bruhl, via email

*I wouldn’t know – as alluded to above, my investment plans at present are to diversify and hold, so I’m not in the market for financial expertise.

People everywhere believe in crazy bullshit. I’m not talking about religious beliefs – any spiritual belief can be defended on the grounds that it’s not a statement about the physical world, and hence not testable. I mean provably false nonsense, like thinking that horoscopes predict the future (they don’t) or that vaccines cause autism (absolutely not) or that cell phones give you cancer (some people are committed enough to this one to keep running studies until they think they’ve found a risk, when really they’ve just finally hit on a false positive). Reading about pseudoscience and urban legends has always been a hobby of mine – I am fascinated the absurd stuff people believe, the reasons they believe it, and the way they react to contradictory evidence. It’s increasingly become relevant to my research as well – a lot of what I work on has to do with what people believe about the world, which often differs from the truth.

Conventional wisdom holds that the poor, and people from undeveloped countries, are ignorant: that they are more likely than people in other places to hold incorrect beliefs or not know about stuff. As I’ve noted here before, my experience is that this isn’t true. I have a previous post that points out the high levels of knowledge about HIV here in Malawi. I wrote it to explain a point that I had seen proven before but couldn’t source, which is that Malawians know more about HIV than Americans. I’ve since learned that the evidence for that is in one of kim dionne’s papers that is currently in the pipeline. Here’s her post on the topic.

In addition to knowing the basics of HIV fairly well, Malawians also don’t seem to believe the crazy shit that foreigners* think they believe. It’s quite common for discussions about HIV in Africa to turn to the “virgin cure” myth. The idea is that people think having sex with a virgin can cure HIV. As best I can tell this is a kind of meta-urban legend, a myth about the existence of a myth. I have seen survey data from Zomba District that asked about this, and about 5% of respondents said that it was true. This is fairly low for something that’s supposed to be a widespread belief and a major causal factor in the HIV epidemic; it’s almost at the point where I’d just say it’s just measurement error, for example respondents misunderstanding the question.** Moreover, at one point I read through all the citations about virgin cures on Wikipedia. There were plenty of cases of whites or African elites asserting that villagers believe in virgin cures, or blaming some horrific rape on such a belief. I came across no evidence of people actually believing in this stuff. I’ve also never seen any quotes from self-professed believers in this idea. I can find you people who will openly espouse almost any belief, on the record: that HIV doesn’t cause AIDS, that we never landed on the moon, that the uterus automatically prevents pregnancy in cases of rape. But I’ve never seen someone say on record that sex with a virgin cures HIV. These people probably exist, but if so they’re rare.

On the other hand, one belief I have no trouble finding open support for is the “blood suckers” rumor. This belief, prevalent in Southern Malawi, holds that when you see white folks in a car (or maybe anyone hanging out in your village in a car) they are planning to come back at night and take people’s blood. The story I’ve heard is that the blood suckers have special pipes or tubes that can go through windows while they remain outside. This rumor first became a big deal around 2004, probably related to the Demographic and Health Surveys, which did take respondents’ blood (in small amounts, in the daytime) to test them for HIV. According to my staff, though, it goes back at least a couple of decades and is also associated with the Red Cross logo and vehicles. Many of my employees assert that blood suckers are in fact real but aren’t associated with white people, and are maybe just evil individuals. The rumor is so commonly accepted that I’ve been openly asked if I was an “opopa magazi” (“blood sucker”, in Chichewa) and had people shout it at us in our project car. It’s also often whispered in my presence, especially by kids. While most kids here are kind of scared of me (hey, I’m weird-looking, who can blame them?), some proportion simply flee in terror the moment they see me.

I have somewhat mixed feelings about writing this post. Wild rumors spread faster than the nightly brushfires here, so in the field I try to avoid even saying the words “blood sucker” (in English or Chichewa), for fear that my words would be misinterpreted. My hope is that posting this here is okay, on the assumption that anyone who believes in that bullcrap isn’t sophisticated enough to use the internet. (Maybe that’s not a safe bet. Plenty of Americans believe even crazier shit and discuss it online – the 9/11 “truth” movement comes to mind.) What I find most interesting about the blood suckers legend is its similarity to other prominent urban myths. Although the name is reminiscent of Latin America’s “goat sucker” (chupacabras) legend, the similarity there is just superficial. Instead, it strikes me as having the same essence as most myths from the US. Fear of strangers, typically characterized by senseless and often anonymous violence, is common to a huge share of American urban legends. The best example of this may be the allegation that people are sticking HIV-infected needles in the coin returns of pay phones or in movie theater seats. Another common theme is a skepticism of authority figures and a belief in conspiracies by the government to do evil things for basically no reason: think of stories about black helicopters or men in black or that weird myth about cows being dissected. Both of these fit right into the blood suckers story.

It also has an attribute in common with lots of conspiracy theories and urban legends about the US government: it adapts to contradictory facts (we’re just doing surveys, and people can see that that’s what we’re doing) by asserting that although there is a legitimate reason for what’s going on, there’s also secretly another very similar thing happening that is nefarious (the same people come back at night and suck your blood). There’s a whole insane literature about “chemtrails” espoused by Americans that asserts that the contrails that come out of jet engines in some weather conditions are really chemicals being sprayed by the government to poison people or do experiments or something. The people who adhere to this legend have had to confront the fact that contrails are real things that naturally occur sometimes. Their response, logically, is that okay, that’s true, but sometimes the government makes things that look exactly like contrails but are instead chemicals being sprayed to kill us. People actually believe this. Fervently. So it’s hard to say that the nonsense Malawian villagers believe is that much worse than what people espouse in the US.

The crazy stories here are no surprise, since they’re not that much crazier than crap that Americans believe – remember, a significant share of Americans don’t think our President was born in the United States. What I find surprising is how similar the underlying themes in the blood suckers rumor are to what I know from American myths. The underlying fears and concerns behind US urban legends might in fact be fairly universal.

*Let’s be honest, we’re basically just talking about white folks here.
**On my current survey I have a question that states “I get pleasure from sex, True/False”. According to my enumerators, some proportion (they think 10%) of respondents think the question is about whether they think the *enumerator* enjoys sex. That question was on another survey and performed really well – measurement errors can be big even with really well-tested survey questions.

One question I get fairly frequently is what an economist is doing studying people’s sexual behavior, and other topics related to public health. There are lots of reasons, but a significant one is that the public health topics I work on (HIV, mostly) are interesting and important, and, moreover, that a lot of quantitative research that comes out of public health schools on these topics is bad. Like, really terribly bad. There’s definitely plenty of very good researchers in that field, but poor-quality empirical work in public health is common enough to be standard water-cooler fodder for certain groups of statistics nerds. The most common offense is for researchers to ignore the title of this blog, and to take two groups that differ in some specific way and attribute any differences in an outcome of interest to that difference. Want to conclude that alcohol makes you smart? Just compare drinkers and non-drinkers in terms of IQ. The former are, on average, smarter. But that’s a ridiculous conclusion; if anything, alcohol kills brain cells and makes you stupid. The problem is that, in the words of my advisor, a lot of other stuff might be going on. The predominant reason for becoming a teetotaler is religion, and higher levels of education tend to decrease religiosity as well as boosting measured IQ. If you don’t account for this, you will get the wrong answer. Unfortunately, this is a great way to make the front page of your university’s news wire/PR wing (every school has one, seriously) and hence the headlines of internet news sites. Chocolate prevents cancer? Fiber recuces your risk of bowel cancer? No, your study is terrible.

The latest offender of this kind comes to me via facebook, and alleges that exposure to semen improves women’s mood and health. The study’s methodology, according to this story from *The Sun*, was to use self-reported unprotected sex as “an indirect measure” of women’s exposure to semen, and look at health and scores on the Beck Depression Inventory. But condom use is related to all sorts of other things – the quality of one’s relationship, trust in one’s partner, STI and HIV status, and hormonal contraception use, to name just a few of the many potential omitted variables here.

Now, maybe that summary is just a poor description of the study, right? No; other than the titillating picture the *Sun* article is basically a paraphrase of the abstract. (Interestingly, this story was picked up just recently but the research is 10 years old). That link is gated, but I managed to dig up this copy of the PDF.* To the authors’ credit, they actually do control for some of the factors named above and find that condom use still correlates positively with depression in women. But that should go in the abstract! In any case they don’t adjust for trust or relationship quality. Here I can’t blame them – those are very hard things to measure on a survey. And they don’t consider the single most important factor: unprotected sex is more fun, feels better, and is more satisfying than sex with condoms. That is going to irrevocably confound any study that uses unprotected sex as a proxy for semen exposure to look at effects on depression – at least as long as it looks at women alone. If the hypothesis is just about semen, and we don’t think that vaginal lubricant has similar effects, you could just look for differences in these results across men and women. I submit that a study of men would find nearly-identical results.

Is it possible that semen improves women’s moods? Absolutely – given the relevant biology, it even seems likely that there’s some effect. But this study teaches us very little about whether there is an effect and how large it is likely to be.

*I did this, and wrote and posted this article, while sitting in my project’s minibus at Mpyupyu trading center, way out in rural Zomba district. Technology is awesome.

Picking aspects of Malawian culture that are superior to the American equivalent has been surprisingly hard. This isn’t because I’m afraid to judge one culture versus another – I’m more than happy to do that, in a serious and thoughtful way. If there’s an opposite for “cultural relativist”, that’s me. If comparing cultures with an eye toward improvement isn’t the definition of development, it’s definitely integral to the concept. As Dr. Robert Siegel pointed out when I was first training to be an HIV educator, “we [HIV prevention campaigners] are here to change culture.” If it didn’t need changing, we wouldn’t be around.

It’s also not that Malawi has no advantages over America. But I wanted to stay away from the bullshit platitudes that usually plague any description of a foreign culture. The worst offender is “hospitality”, which I’ve heard applied to virtually every country. I recently read a piece on foreign tourists’ perceptions of the US which focused on their surprise at our hospitable and welcoming nature. Hospitality is a big thing in all cultures, but it’s shown in different ways so I suppose people always find it striking to see those variations. It’s also usually a bigger deal to welcome a foreigner into your home, versus some guy from down the street.

I’ve also been thinking about stuff the US could actually learn from – I find Malawi’s popular music catchier than America’s, but that’s not particularly actionable. A big one that I think Americans could get on board with is the level of freedom and self-monitoring afforded to the kids here. When school is not in session (which is right now, incidentally) kids in the villages are allowed to just run around and amuse themselves, without a parent constantly hovering over them, not confined to one of those weird playgrounds with the signs that ban childless adults since apparently I am likely to be a child molester. I did a good bit of running unmonitored around my block/neighborhood as a kid, getting dirty, catching bugs, finding cats, and generally having a blast, but that experience is increasingly unheard of in the US; parents there now feel obligated to constantly hover over their children.

Now, mortality is pretty high here, and that is even more true for kids, but the reasons for those excess deaths are largely unrelated to kids running around unsupervised. For reasons that I am very interested in, but cannot explain satisfactorily (yet), people here are pretty unconcerned about what might happen if their kid goes and plays on his or her own. As best I can tell the main risks are snakebites and getting hit by cars driven along crappy roads by stressed-out American grad students – both are rare, but the risk is probably bigger than it would be in the US. Yet Malawian parents are less concerned than American ones, and their kids are probably better-adjusted for it.

My self-interest, by the way, actually runs in the other direction – I kind of wish the parents were doing more hovering here. Since the schools are currently on summer break or something, anytime I park my project’s minibus I attract a small crowd of local kids, who stare at me in terror and usually don’t say anything. I’ve had limited success getting them to play with me, since a) I don’t yet know any games that I can explain in Chichewa and b) more important, they’re often too scared to respond to me. To make matters worse, I often need to do paperwork to get the next batch of surveys ready, in which case I really need them to stay out of the way (and not get bored and start getting in trouble, which is what tends to happen). Today, though, I was just waiting for stuff to wrap up and got a bunch of kids to start imitating my movements, which was a blast. Imagine that happening in America: parents letting their kids go play with some stranger who is driving around the neighborhood in a van? It’s like a textbook kidnapping urban legend.