Category: Economics Profession

Reflections on a semester of blogging

There are many important issues in the news right now that I’d love to write about. There are policy decisions and campaign statements and housing woes and education debates that are all demanding my attention. Unfortunately, so is grading, and a trip to SF, and so I thought I would take a few minutes to reflect on the semester and particularly the inclusion of student blogging in my quantitative methods class this semester.

First, the positives. I really like that my students were writing every week. I think it’s important for their development as thinkers and economists to find ways to express themselves in various ways. Looking over their posts from the semester, I see significant growth in their thinking about econometrics and economic issues in their blogging and am excited to read their final thoughts this week on Donohue and Levitt’s (in)famous abortion and crime paper. I have pretty strong feelings about Freakonomics, but I hope that by reading the Freakonomics chapter, other chapters from the book, the actual paper that prompted the main thesis of the chapter and one of the primary critiques, they can reasonably evaluate the merits and failings of all sides of the argument.

Perhaps one of the most difficult parts of teaching this course has been how to help students to understand that statistical significance is not necessarily the end goal in itself. I’m not grading their papers on whether they found a significant result, but rather their ability to explain it. In reading several chapter of two books, the news, and working through their own research process, I hope that they begin to understand the distinction. I tried to design writing assignments to reflect an understanding of numbers, or coefficients, and will be looking to make that more explicit in upcoming semesters.

All of my students had some great insights throughout the semester. Whether in reading an article in the news and relating that to their research, or finding a connection between a chapter in Poor Economics and some aspect of their own research, it’s been exciting to see them grow and incorporate their lives into their writing and academic work. I’m not sure I made any bloggers for life, but I do hope they all continue writing and finding ways to share their work.

On the not-so-good side, I need to find a better way to track their posts and comments and a better way to ask them to read what each other is writing. Requiring commenting appeared not to be sufficient. I would like to have larger conversations on the blogging platform about the posts themselves. Perhaps requiring everyone read a particular student’s post in a given week and comment there is a better solution. Asking students to read different pieces of books or different articles might solve this as well. Although I think it’s useful for students to read different analyses of a topic they themselves have analyzed, I would like to split the kind of commenting they do a little more in order to expose them to more topics. In addition, much of the commenting was within small groups I only realized existed later in the semester. Students from one fraternity tended to read mostly each others’ posts, for instance. I would have liked to see more integration, but that was my shortsightedness, and it will be remedied.

Related to the issue of topics is the issue of books, reading different books, or more books, or articles may be in order. I chose Poor Economics and Freakonomics for their accessibility and ready discussion of statistics, but surely there are others. I have ruled out More Than Good Intentions by Dean Karlan and Jacob Appel, for reasons I might explicate here some other day, but surely there are others. Perhaps some Dan Ariely, or parts of Hamermesh’s Beauty Pays.

Another significant problem was length. I found it difficult to keep up 25 students worth of writing every week. In the future, I will be stricter and more explicit about length requirements. In order to stay on top of it, and help students develop the skill of writing concisely, maximum word counts are definitely in order.

I’m still exploring ways to better incorporate twitter into the classroom. I know that many of my students read this blog and thus see many of my tweets on the sidebar, but they are still mostly passive readers. Perhaps it’s too much to try to incorporate social media in a class that’s already jam-packed with mountains of new information, but I did like the few opportunities I had to bring it up.

All in all, I think it’s a great way to do writing exercises. Even the limited exposure my students had to outside commentary was useful and a good reminder of how they can use their ideas to shape opinions and contribute to wider conversations. Next time, I’ll do some things differently, but we will keep blogging. You can follow a whole new group of students in the Fall, and even more of them in the Spring! Look for us later on, and of course, you’ll hear plenty from me in the next few months. Thanks for a great semester, for all your thoughts and tweets and emails, and if anyone has thoughts about how to make the student blogging process smoother or more integrative or more useful to students, I’d be very happy to hear your ideas in an email or the comments section.

An abstract

Tuesday was Equal Pay Day, and appropriately, I met with the Vice-Provost to negotiate my contract for next year. He only wanted to give me a one-year contract the first time around, despite knowing that the Economics department needed me and wanted me for two years, so clearly, I was going negotiate again.

Through the course of our discussion, I began to get a little nervous about upcoming calls for papers, conference deadlines and the looming market. As I have told a few of you, I will be on the market again in the Fall, attending the American Economic Association meetings in San Diego in January, and filling out ridiculous numbers of applications as the year comes to a close. There’s lots to be done, but also lots to finish up–getting my dissertation out–and lots to start–new papers!

So, I’m trying to get some papers out and I think I’m close to getting this one done. It’s so hard sometimes, because it’s really so easy just to keep editing, keep running regressions and keep looking for other things to do. But I like this paper. I hope some editor does, too. Hopefully, next week I can share the whole things with you.

Abstract for “Match Quality and Maternal Investments in Children”, Working Paper, April 2012, Erin K Fletcher.

Marriage advocates suggest that the unstable environment caused by divorce can have adverse effects on children’s educational and behavioral outcomes. However, the causal assignment of poor outcomes to the divorce itself fails to take into account relationship quality and heterogeneity in place before or in the absence of divorce. I explore the link between heterogeneity of relationship quality and investments in children. I show that women who report less satisfaction in their relationships spend less time reading with their children. I test various theoretical mechanisms by which we would expect women to decrease their investments in a child using additional information about the match including argument frequency and whether the union dissolves in the future. The anticipation of a union’s dissolution is associated with a decrease in investments in children while the relationship is intact, but argument frequency and mother’s estimation of the father’s character do not have a significant correlation. The results suggest that subjective measures tell a more complete story about investments in children than indicated by future union status, argument frequency or parental quality.

Have a great weekend!

Hot professors get better evaluations

That’s pretty much the gist of the paper. Even controlling for things like age, confidence, etc., professors who are objectively deemed attractive are more positively assessed by their students.

It makes me curious, though. I wonder if there are premiums for being hot based on student and professor compositions. Perhaps departments like economics or physics–where the professors tend to be male and the students primarily male–see higher evaluations for their attractive female professors because they are more novel. Alternatively a sociology department, comprised of more women on both the professor and student side, might give a bigger boost to attractive male professors. The authors seem to acknowledge that this might be an issue given their strategy for selecting students to rate the professors’ appearance.

h/t Bill Easterly and the WSJ

Source: “The Good, the Bad, and the Ugly: Teaching Evaluations, Beauty and Abilities,” Michela Ponzo and Vincenzo Scoppa, Università della Calabria, Dipartimento di Economia e Statistica Working Paper (March) (via Ideas)

The blogging bump (or I am a huge nerd)

I’ve been writing here, on this blog, for a little more than eight months. What started as a way to take a break from finishing my thesis and put down some thoughts about economics has turned into a big part of how I spend my time thinking about economics. Responding to tweets and news articles and other bloggers helps me formulate my thoughts about teaching and my research, and gives me a place to keep track of papers I’m reading. I find it much more useful than EndNote, but that’s perhaps more indicative of the way my head works than anything.

One partly unintended consequence is that I’ve gained a little notoriety. The first time Modeled Behavior tweeted one of my posts, my site stats shot up and I was so confused. I thought someone had made a mistake, then became nervous that Gary Becker had read it and was going to end my career, or something. When discovered the source and tweeted them (him? it? how do we refer to a hivemind?) to say thanks, the hivemind confirmed they had similar fears that elevated site stats were a result of pissing someone off.

With that, I’ve done a very non-scientific survey of bumps. My site stats have, on average, risen over time, but there’s still a noticeable difference when one of the more established economics bloggers tweets or reblogs my stuff. Also, I don’t always know who reblogs or retweets, so if you did and I didn’t mention you, it’s nothing personal, wordpress just didn’t indicate very well to me who you are.

By way of methodology, I wanted to calculate a percentage increase in day-over-day page views, as displayed by WordPress on the day of a tweet or mention. But stats will only let me go back far enough to see three of the bumps. So, the others are cobbled together from my memory. These posts all occurred between February 10 and April 10, 2012.

The biggest bump so far came from a combined DeLong/Modeled Behavior bump. I can’t separate them out with great confidence, but given the second biggest bump came from Modeled Behavior and the magnitude of daily hits was more than twice the sole MB day, so I’m going to give it to DeLong. It’s close though, for sure. Without further ado, my list of blogging bumps, in descending order of magnitude of percentage change (or as best I remember it) in hits on day I was tweeted/reblogged/whatever.

  1. Brad Delong (est. 1005%)
  2. Modeled Behavior (est 610%)
  3. Justin Wolfers (304%)
  4. Tyler Cowen (144%)
  5. Marc Bellemare (est 50%)
  6. Brett Keller (20%)

As I see it, my analysis suffers from a few big problems:

  • heterogeneity of tweets/posts might change click-through rates (did they retweet/reblog because I said something antagonistic about Gary Becker, or just mentioned them, or something else entirely? Did the retweet or reblog contain a link to this blog?).
  • Serial autocorrelation (If hits are high on one day, they’re bound to be high on the next as people read through recent blog entries and tweets, and when retweets were close together, I could be attributing hits to one when they belong to another).
  • Trend over time is also partially due to people coming back because they found me interesting (different, but related to 2, and impossible to know how big or small it is).
  • the time of day. It’s pretty well established that tweets in the morning and mid-afternoon get the most views (or so I am told–please don’t quote me), so retweets/blogs will have differential effects given when both I and the retweeter publish the post. I don’t control for this. (also, days on this blog are on Mountain Time. Colorado, I just don’t know how to quit you. No, really, I don’t know to change it.)
  • unknown retweets/reblogs
  • Popularity of other blogs. (For instance, MB bump came before the Time list of top tweeters came out, so their bump may be even bigger now)

Please don’t judge me (for not controlling for obvious variables. You can judge me for writing this post; that’s fine.)

To weight or not to weight?

Last week, we discussed weighted least squares in my methods class. As a method for dealing with heteroskedastic errors, it has a lot of opponents, notably Angrist and Pischke of Mostly Harmless Econometrics fame. The form of heteroskedasticy, or rather the lack of information about the form, can make weighting a useless proposition. If we’re wrong about the form, which we most likely are, it only introduces further bias.

With regards to population weighting, however, Angrist and Pischke are more clear that we absolutely should weight samples to reflect populations. I’m chest-deep in edits right now, trying to get out my paper on match quality and reading to children, and struggling again with the weighting issue. My advisor, seminar participants at the Census Bureau, and Angrist and Pischke say weight for population. If not, the results aren’t meaningful, or so the story goes.

My gut and a friendly editor say “isn’t it enough to learn about this population itself? Why try to extrapolate to the whole population?” Especially when the sample population was picked to identify particular characteristics, I wonder how or whether weighting is a useful exercise. Or rather, how not weighting is somehow less meaningful.

Any suggestions on how to resolve this internal debate?

How to look rich by not breastfeeding

Almost every time that I’ve presented one of my dissertation papers, someone comes up to me to tell me about some experience they have had that is relevant to my paper. Often, they’re not happy. My paper on parental relationship quality and reading to children tends to really rile up single mothers, all of whom want to tell me how they managed to be good parents despite having unhappy marriages. Mostly, I reiterate how these are average and then just smile and thank them for their input.

Occasionally, though, someone tells me something inspiring, or sad, that really touches me. A student came to tell me about her own experiences with a violent relationship after I presented some of my research, and many others have told me stories about parenting.

Today, I presented the second chapter of my dissertation at the Central Pennsylvania Consortium’s annual Women, Gender, and Sexuality conference. That’s a mouthful, no? My second paper explores the extent to which promises of financial support given to single mothers by the fathers of their children have an influence on financially-constrained investments in children as the child gets older.

As we all finished, a woman who works at the College came up to tell me her story of growing up in Jamaica. She told me how formula was marketed to upper class mothers and so became a sign of wealth. And conversely, breastfeeding became a sign of poverty. Many mothers with few resources, she said, wanted to appear as though they were giving their children formula–the marketed as healthier option as well as the option that signaled ability to pay. Consequently, these mothers would use their limited resources to buy formula, but then would water it down in order to have more opportunities to show they were feeding their children with formula.

It broke my heart to hear it, but it also showcases a rather important problem that economists have. When we rely on survey data and on averages, all of these women would say that they used formula, but likely the nutritional outcomes for their children would be much different. So, not only is there a reporting problem whereby poor mothers might understate for how long and whether they breastfed, but the quality of the alternative has much more variability in nutritional value.

Outside of the measuring problem, I don’t think we’re all that good at identifying these types of what we would call irrational behavior. Without having interviewed women in depth or been there to witness this behavior, we likely would not include it in our analysis, leading to biased estimates.

RCTs and placebo effects

A few weeks ago, a paper was posted on the CSAE 2012 Conference website that seemed to fly in the face of much of the current research that is happening in development economics. The advent of RCTs (randomized control trials) brought about a significant change in the way we do policy analysis, but also in the costs of it. This paper suggested that RCTs were capturing placebo effects. Just like when people believe they are taking curative medicines, they feel better, so do those benefiting from RCTs experience placebo effects from knowing they are part of an experiment.

The answer, according to the researchers, is to conduct a double-blind experiment, where neither the researchers nor the participants whether they were part of the treatment or control.

The paper garnered a lot of attention early on. I noticed many colleagues and others had the immediate and short reaction of “wow” and “yikes”, and I wasn’t the only one. Berk Ozler, at the Development Impact Blog, has a good review of the paper up with a great, punny title. Among other problems:

First, it turns out that the modern seeds are treated with a purple powder in the market in Morogoro (to prevent cheating and protect the seed from insect damage during storage), so the experimenters sprayed the traditional seeds with the same purple powder. As you can immediately tell, this is less than ideal. First, as this is a not a new product, farmers in the blind RCT are likely to infer that the seeds they were given are modern seeds. Given that beliefs are a major part of the story the authors seem to want to tell, this is not a minor detail. Second, if the purple powder really does protect the seeds from insect damage, the difference between the MS and TS is now reduced.

Berk’s analysis is well worth a read. Kim Yi Dionne also addresses placebo effects, though a different paper.

Update: the original post said that this paper was forthcoming in Social Science and Medicine. This is not the case. Sorry for the confusion and thanks to Marc Bellemare for catching it.

Update #2: The Economist has a nice review of this paper up as well on the Free Exchange blog. It doesn’t touch most of the analysis issues, but it does explain well why double-blind experiments might not be useful in Economics. h/t @cdsamii

On E-Universities

Megan McArdle tackles the future of society and universities in a recent article at The Atlantic. In response to a post on the future of universities by Stephen Gordon at the Boston Globe, she enumerates her predictions for how societies will change if universities change to a totally online model.

Both McArdle and Gordon place great emphasis on cost, and perhaps not wrongly. Gordon claims that because they can hire an MITx credentialed student for cheaper than a regular university grad due to lack of student loans, the MITx model win win. McArdle says that the economies-of-scale that result will make us all go to the cheaper option and she thinks that’s good. But there are a couple of assumptions that are implicit in the analysis that I find incredibly disturbing. And not just because it would likely put me out of a job.

The first is that it’s valuable to have everyone learn the same thing. I find this horrifying. Yes, it’s useful if everyone used the same computer programming language, but if they did, then things wouldn’t progress. They become entrenched, like the QWERTY keyboard, which we all know is inefficient, and yet we learn and use it anyway. I think it’s great that most economists use Stata, but I also think it’s great that some use SAS, so that if I needed something done in SAS–which handles large datasets much better, while Stata is perhaps simpler to learn–I could get it done.

I want to know people who have read different books and studied different thinkers and learned different ways of studying or learning about the world. I think life would be incredibly boring otherwise.

Secondly, though McArdle mentions it, I think both authors severely underestimate the networking effect of college. McArdle says that we’ll need to find a different way to essentially make friends, but I think it’s more than that.

People I know from college represent not only many of my close friends, but also collaborators, colleagues, coauthors, references, providers of services, and directors of charities I support. If I wanted to go into investment banking or consulting or medicine or some other field, I have a list of people I would call for advice and to let them know what I was hoping to find, work-wise. I’d imagine that at least one Duke alum, if not many, would aid in my career change or become a client down the line.

This is not unique to Duke. If I’d gone to CU or Stanford or UVA or Metropolitan State, those networks would still be important. And important to my employer, not just to me. I think employers recognize this. Education signalling is not just about quality (regardless of noise levels), there’s also an assumption that who you know might matter at some point, as well.

Besides, what the heck are journalists going to cover if researchers aren’t putting out papers and books?

For Valentine’s Day, on love and marriage and economics

Perhaps I’m hyper aware of things going on in both media and social media these days, but it seems that UPenn economists Justin Wolfers and Betsey Stevenson are everywhere these days. They’re all over my twitter feed for one. Then, today this came out in the Washington Post, and over the weekend, out came a profile in the NYT. The Times article describes them as a ‘power couple’ of economics. Which is pretty funny if you know any economist couples.

Though our research hasn’t come head to head yet, Justin and Betsey do a lot of work in family economics, much like I do. So, their meteoric rise to national prominence (at least among the WaPo-, NYT-reading set, is of interest to me. In particular, someone mentioned a quote from Betsey Stevenson saying that the household problem (as we so lovingly call it in economics) had turned from one of shared production to shared consumption.

Much of the dominant thinking in family and household economics has roots in Gary Becker’s A Treatise on the Family. It rests on ideas that can only politely be called antiquated. Women are in charge of domestic production (cleaning, child-rearing, cooking, laundry, etc) and men are in charge of bringing home the bacon. It’s specialization at the household level. Very economist-y. On some level, it probably made a lot of sense to think about marriage in this manner, particularly when women’s wages were much, much lower than men’s. In fact, it made so much sense that it partly earned Becker a Nobel Prize in Economics.

At some point during my fourth year of graduate school, I ordered my own copy. It was a simple (though really expensive!) purchase. A paperback, just a book, but a book that essentially formed much of the dominant thinking in my field. Even then, I knew its time in the spotlight was waning. I’ve still never read the whole thing. Despite knowing it was a classic, I can still only look up passages when I think they’re relevant. Reading more than a few pages makes the feminist in me absolutely boil.

But someone else recently said that, as economists, we should hope that our research becomes irrelevant, because that means that society has changed or that we’ve developed policy solutions for those questions and problems. And that’s probably what is happening here.

The world is changing; marriage is changing, love is changing. Household production is definitely changing. And perhaps all of this is about household consumption (enjoying kids and raising them together) rather than household production (raising kids, a public good). I’m unsure whether this is true at every socio-economic level, or whether it’s a privilege of high-earners, but it’s certainly an interesting way to frame and model marriage in economic terms.

Happy Valentine’s Day!

Elsevier boycott update

Here is the list of academics who’ve signed on to the Elsevier boycott. I found it today after re-reading something that @LSEImpactBlog had re-tweeted (I hate it when an outlet changes the name of something and I re-read and don’t realize it). But I was also curious about the number of economists who have signed on.

Perhaps unsurprisingly, the absolute number is very small. While mathematicians–of whose one own started the call for the boycott–and physicists are signing on in large numbers, only 41 economists have signed it. This represents less than 1% of the 4676 signers. I don’t have numbers, but economics is a pretty large field. I’m fairly certain we represent more than 1% of academics.

The only field with fewer signers is Statistics, with 29.

I’m curious, naturally, about why this is. Are economists worried that a boycott might hurt them more and more risk-averse and thus not signing on? Are we by nature less likely to participate in boycotts? Are we just not paying attention? Is there a belief that the boycott will be unsuccessful? Are we free-riding?

I have a paper with a coauthor that we’ve been working on for awhile. Before the boycott stuff came out, we had discussed where to send it next and an Elsevier journal was on the list. While neither of us has signed the boycott declaration, we have discussed the decision. Whether or not we decide to boycott officially, others’ decisions about whether to boycott will affect our paper’s publication process. More boycotters mean fewer reviewers available, and might lead to less appropriate reviewers (on average). It might mean longer response times as referees decide whether to join the boycott.

Of course, this could all work in our favor, too, as turnaround times could decrease with fewer submissions. But in turn, this could result in the decline of journal importance, if good papers aren’t going to Elsevier journals.

Maybe we just think about things too much…