Category Archives: Anthropology

Risk-Aversion and Finishing One's Dissertation

It's that time of the year again, it seems, when I have lots of students writing proposals to submit to NSF to fund their graduate education or dissertation research.  This always sets me to thinking about the practice of science and how one goes about being a successful scientist. I've written about "productive stupidity" before, and I still think that is very important. Before I had a blog, I composed a series of notes on how to write a successful NSF Doctoral Dissertation Improvement Grant when I saw the same mistakes over and over again sitting on the Cultural Anthropology panel.

This year, I've find myself thinking a lot about what Craig Loehle dubbed "the Medawar Zone." This is an nod to the great British scientist, Sir Peter Medawar, whose book, The Art of the Soluble: Creativity and Originality in Science, argued that best kind of scientific problems are those that can be solved.  In his classic (1990) paper Loehle argues that "there is a general parabolic relationship between the difficulty of a problem and its likely payoff." Re-reading this paper got me to thinking.

In Loehle's figure 1, he defines the Medawar Zone.  I have reproduced a sketch of the Medawar Zone here.

medawar-zoneNow, what occurred to me on this most recent reading of this paper is that for a net payoff curve to look like this, the benefits with increased difficulty of the problem are almost certainly concave.  That is, they show diminishing marginal returns to increased difficulty.  Hard to say what the cost curve with difficulty would be – linear? convex? Either way, there is an intermediate maximum (akin to Gadgil and Bossert's analysis of intermediate levels of reproductive effort) and the best plan is to pick a problem of intermediate difficulty because that is where the scientific benefits, net of the costs, are maximized.

Suppose that a dissertation is a risky endeavor.  This is not hard for me to suppose since I know many people from grad school days who had at least one failed dissertation project.  Sometimes this led to choosing another, typically less ambitious project.  Sometimes it led to an exit from grad school, sans Ph.D.  Stanford (like Harvard now, but not when I was a student) funds its Ph.D. students for effectively the entirety of their Ph.D.  This is a great thing for students because nothing interferes with your ability to think and be intellectually productive than worrying about how you're going to pay rent.  The downside of this generous funding is that students do not have much time to come up with an interesting dissertation project, write grants, go to the field, collect data, and write up before their funding runs out. So, writing a dissertation is risky.  There is always a chance that if you pick too hard a problem, you might not finish in time and your funding will run out. Well, it just so happens that the combination of a concave utility function and a risk of failure is pretty much the definition of a risk-averse decision-maker.

Say there is an average degree of difficulty in a field.  A student can choose to work on a topic that is more challenging than the average but there is the very real chance that such a project will fail and in order for the student to finish the Ph.D., she will have to quickly complete work on a problem that is easier than the average.  Because the payoff curve with difficulty is concave, it means that the amount you lose relative to the mean if you fail is much greater than the amount you gain relative to the mean if you succeed.  That is, your downside cost is much greater than your upside benefit.

risk-aversionIn the figure, note that d1>>d2.  Here, I have labeled the ordinate as w, which is the population genetics convention for fitness (i.e., the payoff).  The bar-x is the mean difficulty, while x2 and x1 are the high and low difficulty projects respectively.

The way that economists typically think about risk-aversion is that a risk-averse agent is one who is willing to pay a premium for certainty.  This certainty premium is depicted in the dotted line stretching back horizontally from the vertical dashed line at x=xbar to the utility curve.  The certain payoff the agent is willing to accept vs. the uncertain mean is where this dotted line hits the utility curve. Being at this point on the utility curve (where you have paid the certainty premium) probably puts you at the lower end of the Medawar Zone envelope, but hopefully, you're still in it.

I think that this very standard analysis actually provides the graduate student with pretty good advice. Pick a project you can do and maybe be a bit conservative.  The Ph.D. isn't a career – it's a launching point for a career. The best dissertation, after all, is a done dissertation.  While I think this is sensible advice for just about anyone working on a Ph.D., the thought of science progressing in such a conservative manner frankly gives me chills.  Talk about a recipe for normal science!  It seems what we need, institutionally, is a period in which conservatism is not the best option. This may just be the post-doc period.  For me, my time at the University of Washington (CSSS and CSDE) was a period when I had unmitigated freedom to explore methods relevant to what I was hired to do.  I learned more in two years than in – I'd rather not say how many – years of graduate school. The very prestigious post-doctoral programs such as the Miller Fellowships at Berkeley or the Society of Fellows at Harvard or Michigan seem like they are specifically designed to provide the environment where the concavity of the difficulty-payoff curve is reversed (favoring gambles on more difficult projects).

There is, unfortunately, a folklore that has diffused to me through graduate student networks that says that anthropologists need to get a faculty position straight out of their Ph.D. or they will never succeed professionally.  This is just the sort of received wisdom that makes my skin crawl and, I fear, is far too common in our field.  If our hurried-through Ph.D.s can't take the time to take risks, when can we ever expect them to do great work and solve truly difficult problems?

More on Diamond

I've been thinking some more about the issues that are raised by the debacle over Jared Diamond's 21 April 2008 New Yorker piece and the recent announcement of a lawsuit against him.  There are many things to think about here.  Probably foremost amongst these are the ethical concerns relating to preserving research subjects' privacy and informed consent.  There are secondary concerns regarding scholarship, standards of research, and obligations to adequately describe research methodology.

I am troubled by a point raised by Alex Golub in the Savage Minds blog. Golub writes, "There is also a more serious problem with [Diamond's New Yorker] article which is also the most obvious thing about it: it contrasts ‘tribal societies’ with ‘modern state societies’. "  This is something that bothers me too though I think that my response may be somewhat different than that of many contemporary cultural anthropologists. In general, I have sensibilities very much akin to Diamond's. I see tremendous value in comparative studies, and I think that there is something that we can call, for lack of a better term, a robust and fairly general Human Nature.  Human beings are biological entities with material needs and (many) material motivations and we ignore these at our explanatory (and possibly literal) peril.

The Myth-of-Isolation criticism, which also arises in the Diamond debacle, is not new in Anthropology.  I am reminded of the Kalahari Debate of Lee, Wilmsen and others. Globalization as a phenomenon of anthropological inquiry has certainly increased in currency of late and I think that this scholarship tends to make many of my colleagues skeptical of any research on, say, foraging decisions by hunting and gathering people.  The answer to this criticism is that foraging people in a globalized world, like all people, still make decisions about what to eat, what not to eat, how to eat, etc.  Their choices may be constrained by a hegemonic state or by extra-state organizations, but choices are still being made.  Understanding how such choices are made in a globalized world strikes me as being at least as important as it was 50 or 100 years ago.   This goes for hunter-gatherers as well as urban elites, agrarian peasants or just about anyone else.

Rather than taking labels such as "tribal" or "state" as sufficient descriptions of the differences between groups, I think that the science requires us to describe (and hopefully quantify) the dimensions of their difference.  I have been thinking a lot about social networks lately.  One dimension on which two societies might differ is the composition of ego networks.  How many people does a given person know?  What fraction of those are kin?  What is the gender composition of the ego network? How socially similar are the member's of ego's network to him/herself? How many would provide emotional/economic/agonistic support to you in a crisis?  Does an individual's ego network include socially important figures like government functionaries, doctors, lawyers or the equivalent? How much does ego's network overlap with his/her spouse's? Brother's? Neighbor's? Member of the next village/town? Gathering such data is clearly a major undertaking, but that's what science is about, no?

The fraught question of how to do ethical, meaningful anthropology in a globalized world that struggles with the legacy of colonial depredations has, in my view, driven too many anthropologists from science. Protecting human subjects and doing unto others what we would have done to us are important guiding principles for anthropological research, indeed, any research in the human sciences.  Describing -- and, ultimately, understanding -- how societies differ and what the implications of these differences are for human behavior should, in my opinion, be another principle.  Facile labels relating to social or economic complexity, ethnicity, religion, nationality, etc. do not help us understand the diversity of human behavior.

Jared Diamond and Anthropological Ethics

Brian McKenna sent around to the EANTH Listserv a couple of blog posts today detailing the trouble that Jared Diamond has gotten in about a New Yorker story he wrote a year ago on the power of vengeance.  This seems like a rather sordid affair but I think that Alex Golub should be commended for his very fair treatment of it in his most recent post on the Savage Minds blog.  It certainly sounds like there were some major ethical lapses in the production of Diamond's New Yorker piece, though I wonder about the motivations of Shearer, the muck-raker who has brought these issues to light.

Jeanine Pfeiffer, the director for social science at the Earthwatch Institute, posted a list of ethical guidelines from the International Society for Ethnobiology which I think are very relevant for understanding the apparent ethical lapses in Diamond's work. Honestly, I can't imagine publishing an article like Diamond's and using the informants' real names!  Then there's the issue of informed consent.  People need to know that they are "on the record" -- whatever that means in this (kind of) grey area of anthropology-meets-journalism. Seems to me that minimal twin standards that should guide anyone's writing about the lives of people "in the field" include: (1) would you write this way about people in your own immediate community? and (2) would your article's evidentiary and rhetorical standards pass muster if it was a paper submitted by an undergraduate for a class you were teaching?

As Golub notes, Jared Diamond is an easy target for academic anthropologists (or historians or geographers) because he writes well and clearly about complex topics and reaches a large audience.  There are always people grumbling about Diamond's originality, authenticity, and willingness to attribute ideas to others (in that vein, a highly recommended book). Diamond's ecological work on community assembly of pigeons in New Guinea is top-notch and I still assign his chapter from the Ecology and Evolution of Communities volume he edited with Martin Cody in 1975. Regarding books like Guns, Germs, and Steel or Collapse, I take them for what they are: synthetic popularizations that maybe could have stood a little more attribution.  It would certainly be nice if the popular spokesperson for Anthropology were actually an anthropologist. Alas, anthropologists, for the most part, have given up on the goal of writing prose that can be broadly read, appreciated, and understood.

This is a story I will be keeping my eye on.