Recent articles by Alan B. Krueger
Romesh Vaitilingam: Welcome to "Vox Talks" a series of audio interviews with leading economists from around the world My name is Romesh Vaitilingam and today's interview is with Professor Alan Krueger from Princeton University We met in October 2008 at the Center for Economic Performance in London, which was hosting a workshop on happiness research. Alan and I spoke about his work on physical pain and wellbeing He began by explaining how he got into this field
Alan Krueger: It actually goes back about eight years when Danny Kahneman invited me to join a group of psychologists that he was working with on wellbeing. I remember he said he has the dream team of psychologists working on this issue, but to have an impact on public policy they needed an economist I found that flattering and I joined up. The work has been evolving over time. The latest development for me has been to work on, specifically, on the issue of pain. I think everybody could agree that pain is a bad thing, or at least, you don't want too much pain in your life
Maybe pain when you exercise is good to have because it's outweighed by other factors, but one of the things that we found is that people who live in pain really live different lives, much less fulfilled lives So, let me back up a little bit
The techniques that we've developed over the last eight years: We started with the idea of experience sampling: trying to measure how people feel during the course of their day in real time. We quickly discovered that it's very difficult to implement that type of survey technique in the general population
So then, we looked for ways in which we could have people keep diaries, a day later, describing what they did the day before in a lot of detail and reporting on their emotional experiences during the day. Those results seemed to mirror pretty well what one finds with the experience sampling technique. You could use these other techniques for more general populations.
So, earlier this year Arthur Stone and I published a paper in the journal Lancet assessing the extent of pain in the US population. It's the first time, really, that pain has been studied in the entire population of the US. There was one previous study, which had a very vague question about how much pain people had
What we could do is we could look moment by moment. We could say, "What fraction of time does the average person spend where they some pain, how about where they have moderate to severe pain? How does it vary by groups?"
And the results we found, I think, were absolutely fascinating. Some we expected, some we didn't. For example, as people grow older, or to be more precise we're looking at people of different ages in a point in time, pain seems to rise for people who are older, but not in a constant fashion; there was a very long plateau.
So, pain increased from people from their late teenage years up until the early 40s. Then there was a plateau from the mid 40s to the mid 70s It was more prominent for men, but it was also there for women We were really quite surprised to see that. We concluded our paper saying that this needs to be replicated. If it can be replicated, we need to figure out what's going on here.
So today, I first showed that finding and then I showed how we replicated it, and we replicated it in two different surveys; one, a very large survey of the US, which the Gallup organization has been doing, and then the second one, which is really more interesting, is a survey that Gallup has been doing in about 140 countries.
It's not quite as precise as what we studied, but pretty close. They asked people in each of these countries, a large sample of people, "Did you experience pain during a lot of the day yesterday?" Then we could see what fraction of people experience pain during a lot of the day yesterday. The US and the UK really stood out for having this plateau What was fascinating, if you look at lower income countries, if you look at Africa, parts of Asia, you see pain rises with age monotonically It starts at a higher level in the poorer countries and it really diverges at the older ages. So, one of the things I concluded from this work is that the UK and the US are good places to grow old in.
We've been trying to understand what it is that accounts for the patterns that we're finding. A related pattern is looking within the US, and of the other countries as well, we find very strong income effects on pain. Low income people experience a lot more pain in their daily lives than high income people
In the US, people who make less than $30,000 a year, or households that make less than $30,000 a year, the average person spends about 18% of their time in pain; in moderate to severe pain. In the high income households, more than $100,000 a year, they're just spending 7% of their time in moderate to severe pain. So, there's a tremendous gap in the way that they experience life. Those things seem to be connected, especially at the older ages; high income people seem to be more resistant to pain. We're not entirely sure we know why.
I think part of the explanation has to do with occupational structure. Lower income people tend to work in jobs that are more physically demanding. That's something that we can show in our data blue collar workers, while they're on the job are experiencing more pain than they feel when they're off the job. You don't see that for the white collar workers: it's about the same amount of pain on the job and off the job
There are other possible explanations too It could be related to pain medication, lifestyle and so on
Romesh: What do you think the issue is about causality? Does it go from pain to, therefore, having lower socioeconomic status because you're less able to work and earn a good wage or is it going the other way around? How do these things interact with each other do you think?
Alan: Right, well I'm confident that the arrows go in both directions. It's harder to separate how much they point in both directions, but it's certainly the case in the data that we have that people who have a disability are in a tremendous amount of pain and have very low employment rates and very low income when they do work. Clearly I think one arrow goes from chronic conditions to disability, to withdrawal from the labor force, to low income. But I suspect another channel, as I mentioned before, is through occupation. It's not only a matter of kind of withdrawing from the labor force because if we look specifically at people who are employed, we still find that those who are employed at lower wages tend to have more pain in their daily lives.
So I suspect that causality goes in both directions. In another level, we certainly care about unraveling the direction of causality, but I would say we also just care about pain itself. We care about characterizing who it is who experiences pain, because pain is an outcome of interest all by itself.