Mailund on the Internet

I just saw this post today linked to from Bitesize Bio’s Around the Blog. It bears the title “Postdocs always overestimate their intellectual contributions” but really is about the relationship between postdocs and PIs, as seen from the postdoc perspective (and an under-appreciation of the PIs work).

Life as a postdoc

The postdoc (and grad student, for that matter) perspective is — and I recognize it both from my own experience and my colleagues — that you come up with most of the ideas, do all the work, and the PI just takes the credit. It is a bit exaggerated, but the point is that the vast majority of the time spend on a project is time spent by a postdoc or grad student. The advisor reads the occasional draft paper, comment on the research a bit here and there, but doesn’t really put in the hours.

I think this is true. I think this is absolutely true (and on this point I think I disagree with the post I link to above… or maybe not when I elaborate on the point…)

Before I elaborate, though, I should probably explain my own situation, so you know where this perspective comes from.

I am somewhere in between being postdoc or PI. The last couple of years I have been working on my own grants and not really been associated with any particular group, so I haven’t been a postdoc as such. Although I’m currently officially an associate professor, I am not associated to anyone, and I haven’t got tenure yet so I cannot start my own group. With the current rules in Aarhus, I cannot have grad students associated either. Instead, I have associated myself to different other groups, for individual projects, and when doing so take on roles as either “postdoc” or “advisor”, depending on the project and who else is involved.

Anyway, the situation is that I was relatively recently a postdoc — and remember how I felt about academic life then — and now I have experienced both the advisor and the postdoc world (but so far have never really been responsible for my own group, so my perspective might change later on).

So, as I said, I think it is true that on any one project, the postdoc will be doing the vast majority of the work, at least measured in hours. This isn’t really surprising. The postdoc can focus on one project (or a few projects), while the PI needs to manage many. Of course the postdoc will contribute the most time — but who contributes the most research?

Division of labour

This is a trickier question… first of all because it is not easy to define nor measure “research”. The best measure we have is the publications, but within a project you cannot use it to measure the output of the first author vs the last author.

The PI will be more experienced (or at least should be, but I’ll come back to that) so he will have a better idea about how to approach a problem, he will be able to spot dead-ends long before the postdoc, he will know the literature better, etc. This is all experienced he gained when he was the one doing the grunt work, and now he should use it to teach the postdoc. A PI hour might simply be worth more than a postdoc our because of the extra experience.

That is not the whole story, though. There is also what I would call a trade-off between “detail work” and “big picture”.

Most research is fiddling with details, trying to make epsilon improvements upon previous work. We all dream of a great breakthrough, but day to day research is about epsilon improvements, and that means fiddling with details. It requires a lot of work to fully understand the details of any kind of problem, and it is very easy to get lost in details and lose the big picture. How does the current work fit into the larger problems in a field, how does it related to previous work, and what will be the consequences of whatever you are trying to prove or solve? Someone needs to figure out the details, but someone also needs to keep the big picture in mind!

I’m not sure you can do both at the same time. At least I find it difficult to do both at the same time.

The postdoc deals with the details, and is probably the only one who fully understands the problem being worked on. The PI keeps the big picture in mind, trying to relate the current problem to the rest of the field.

The PI will spend less time on the particular problem — contribute fewer hours to the project — but at the same time he probably needs to keep up with a broader part of the literature and keep track of related projects to improve on this project. It doesn’t feel like he is contributing to the specific problem when he is just reading papers about other peoples work, but the hours he put in there helps him keep an eye on the big picture instead of getting caught in the details.

One of the perks is, of course, that keeping up with the literature pays off for more than one project at a time, so you get more publications that way. As I said, it is one of the perks of that side to research.

Experience matters (if you have it)

One thing is the “details” / “big picture” division, but another is experience. The postdoc will be less experienced in doing research. The whole package, including doing the actual research, writing the papers — just as important as doing the experiments and analysing data, really — applying for grants, etc. This is stuff you learn from experience, and is a lot easier to learn with the assistance of someone who already has the experience. That would be the PI.

The postdoc is still learning. He is being taught (or should be taught) by the PI. It might not feel like a student/teacher relationship, because it is very different from the typical teaching at a university, but it is such a relationship. It is just more of a master/apprentice relationship. The apprentice starts out doing only the grunt work, but gradually does more and more of the complicated work under less and less supervision, until he has mastered the discipline.

Experience is mainly a way to avoid dead ends, in my experience (no pun intended). When you have worked with something for a long time, you have a good intuition for what might work and what will not, so you avoid a lot of wrong turns. The experience of the PI will help the postdoc avoid a lot of pitfalls (probably without ever realising that there was a potential pitfall). There should be room for making mistakes — that is how we learn — but by supervising the postdoc, the PI can help to avoid the worst mistakes. By supervising less and less, leaving room for some mistakes but not until the postdoc is ready to deal with them, the PI allows the postdoc to gain the experience while still being a bit sheltered.

When supervising, it is actually harder to allow someone to make a mistake than it is to spot a mistake and avoid it, but sometimes mistakes are necessary to learn, so they should never be totally avoided… but that is a topic for another day…

Will the PI always be more experienced? Many paragraphs ago I promised to get back to this point. In most ways I would say yes. Writing papers, applying for grants, that stuff he should be more experienced. Otherwise he wouldn’t be the PI, really. But there is a limit to that experience and that is also important to keep in mind.

There’s two scenarios where the postdoc will be more experienced than the PI. If the project he is working on is outside the PIs previous experience, or when the detail-work is important but completely lost to the PI.

Let’s take the first scenario first. The PI gets an idea. “It could be fun to figure out if …” and although it is not really related to anything he has done before, he manages to get a grant for doing research on the project. He has the grant but not the experience. So he hires a postdoc to work on the problem, but cannot really supervise the science! (This is not as made up as it might sound; I have seen it happen a couple of times…)

The second scenario is probably more common. Here the problem is that by focusing on “the big picture” for so long, the PI has forgotten the details and ignores that that is where the problems really are. The big picture might tell you what the important questions are, but the answers are found in the details. People forget this too often, in my opinion. They ask an interesting question and then suggest “maybe you can solve it using an MCMC or something…” or “maybe you can solve it using dynamic programming…” but that is not a helpful suggestion at all! It is a complete disregard for the details, and the details are important (damn it)!

You loose the feeling for the details if you keep away from the for too long, and when that happens you cannot teach others how to deal with them any more.

Of course, a PI will never be as much into the details as the postdoc working with them every day, but luckily most problems are somewhat similar so what works in one setting might work in another so some experience is transferable. This is why experience can be substituted for hard work in many cases.

Sometimes the experience just isn’t there (for either of the two reasons I mentioned), and in that case the PI isn’t pulling his own weight on the project. A few general remarks to a draft and completely generic comments to solutions (”have you considered an ABC solution?”) are of little help. In such cases, I think a postdoc would be right in thinking that the PI just gets the credit but doesn’t do the work. Fortunately, it is not something that happens that often, and most PIs would recognise that they are not actually capable of helping with the problems and try to improve on it by getting to know the details a bit better.

Life as a PI

Being in transit from postdoc to PI I’ve noticed a few things that I never really thought about before. New problems when you are no longer a postdoc in a group. I’ve probably only noticed half of the new problems, since I have yet to experience running my own group.

Anyway, the most important difference, the way I see it, is related to the “big picture”/”details” thing. I no longer have time to focus on just a single problem for days or weeks. There is always a lot of different projects that requires my attention, and that means that I cannot put in the time really necessary to solve detailed problems. It is something I really miss, being able to completely focus on a problem for a couple of weeks, until I have it nailed. If I want to do that now, I have to do it in my vacation.

Another thing is the time it takes to come up with those few suggestions to drafts and projects. I would have guessed that you would spend half an hour before a meeting and that would be the time you would put into it when supervising a project. Maybe some people can do that, but I find that to really think about it I need to spend hours. Checking the literature, doing the math to check out if it works out, looking over the data with my own simple methods to get a feeling for it. It is not enough to get the feeling for the details that is really needed — as I said, there simply isn’t the time for it any more — but it takes a lot longer than I would have thought.

I’ve already begun to think of the postdoc days as the good old days, but I fully remember being envious of the PIs at the time. Over the coming years, if I get tenure, I will get more and more administrative and teaching tasks and I might end up missing the postdoc time even more.

Tags: Research life

This entry was posted on Friday, May 9th, 2008 at 2:28 pm and is filed under Work. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.