Sunday, November 17, 2013

Multitasking or Parallel vs Serial Thinking

It is useful to know what one is good at, but also what one is bad at. 

The example I am thinking of is multitasking, doing and thinking about several things at once. The first clear evidence of my inability to do it well appeared decades ago in the context of my medieval hobby, which included combat with medieval weapons done as a sport. I was much worse at melee combat—one group of fighters against another—than at single combat. In single combat I only had to focus on the opponent I was fighting. In melee, I had to be, or at least should have been, simultaneously keeping track of everyone else near me. And I wasn't.

The same problem showed up much later in the context of World of Warcraft. Group combat there, a raid with a group of from five to forty people, requires the player to keep track of what he is doing, what other people in the group are saying—in the form of typed messages on the screen—and other things going on around him. I focused on what I was doing and frequently missed important things other people were saying. Interestingly enough, that was less of a problem if the group was using software that permitted voice communication, so that one kind of information was coming in mostly through my ears, another through my eyes. 

It is not just that paying attention to multiple things is hard. My daughter, playing the same game, can not only pay attention to everything in the game, she can also conduct one or two independent conversations, in typed text, while doing so. Pretty clearly, it is a real difference in abilities, whether innate or learned I do not know.

Thinking about it, it occurred to me that I had observed the same pattern in an entirely different context, the difference between how I think and how Richard Epstein, a friend and past colleague, thinks. I usually describe the difference as my thinking in series, Richard in parallel. It shows up when he is sketching the argument for some conclusion. 

A implies B. B implies C. C ...

At which point I demonstrate that B doesn't really imply C, that there is a hole in the argument. That is no problem for Richard, who promptly points out that A also implies B', a somewhat different proposition than B, which implies C', from which he can eventually work his way back to D, or perhaps E or F, and so to the conclusion that the original line of argument was intended to establish. Pretty clearly, he is running a network of multiple lines of argument in his head and only has to find some set of links in the network that gets him where he is going. I am focusing on running a single line of argument. Hence parallel vs series.


Tibor said...

I don't know if it really is true, but the popular "knowledge" is that women are generally better at "parallel thinking" (or multitasking if you will) than men are.

Playing drums is also quite an intersting thing from this pespective. Some things are better understood in of the drumset make a single melody together, albeit some notes are played together (even though you can even play strictly in single notes which sometimes leads to interesting grooves). But especially in latino music where the drummer basically takes a role of a couple of musicians who otherwise play in a traditional band, it makes much more sense to separate your limbs in your mind and percieve them separately. It is arguably harder. I wonder if these styles are on average easier for female drummers or not.

Some people are much more extreme than not being able to keep two conversations at once. A friend of mine cannot type an sms message and walk at the same time, or at least it is very hard for him. Otherwise he is an intelligent guy who does mathematical modelling and works as a research assistant in a computer security company, but this he is really bad at.

The other extreme is some people who are able to type a text message and talk with someone at the same time...I know a few (and all are women, so that is at least a weak evidence for that "popular knowledge") people who can do that but for me this is extremely hard and I can only do it with very simple messages (ones I don't have to think about and type them almost automatically, such as "yes, I will be there at 8pm").

bruce said...

Jacques Barzun thought good detective stories were a golden mean between the appropriately flat-footed story of police routine, no drama or real story at all, and the feminine mistakes of HIBK (Had I But Known to apply ordinary judgement) and EIRF (Everything Is Rather Frightening when purple prose cranks up high enough). HIBK:

" ...books that chiefly mirror the typical aspects of women's lives are not made into detective stories by the perfunctory addition of a crime and a policeman.

"What are these typical aspects? The briefest answer is : household confusion. The actual scene of the story may be a hospital or a college, but the state of mind is that of a kitchen. It is marked by interruption, changes of plans, minor mishaps that pass for catastrophes, surprises, and lucky recoveries- all highly verbalized and widely communicated. All of life could no doubt be described in terms not very different: it is a matter of degree. But domestic life, by its nature and for its great purpose, remains extraordinarily discontinuous- the perpetual readjustment of small intentions. This in turn generates a characteristic tone, which one finds faithfully rendered in the "feminine" detective tale."

Kid said...

I am part of the younger generation that is supposedly good at multitasking.

What I notice is that the 'secret' to multitasking is spending very little time on each task. Not surprisingly, that reduces how effective, and especially how innovative, you can be on that task. Sometimes that is OK.

If you wanted to get better at multitasking, I think you ought to practice doing tasks really quickly with a minimum amount of attention.

If you need to multitask spellcasting, for example, you'd take less than half a second executing the muscle memory for it, and then move on to surveying the environment. You don't need to watch your character cast.

Age factors into it in terms of processing speed, perhaps. But even older people can get quite reasonably good at multitasking with practice. It just so happens not to be their generation's 'natural' way of operating, so it's outside of the comfort zone at first.

Simon said...

But is multitasking and parallel thinking the same phenomenon? I'd describe myself as a highly parallel thinker but a mediocre multitasker. One could perhaps describe parallel thinking as internal multitasking: you have to keep several threads simultaneously in memory. But while I'm internally multitasking, the food I started cooking is burning on the stove.

Unknown said...

My Father in Law, a retired Psychologist, maintains that a number of common mental disorders like schizophrenia or manic/depression are actually overly reinforced beneficial traits of human survival. People frequently benefit from the milder aspects of creativity from the disorganized thinking patterns within schizophrenia or from the production during a mild manic phase. If the benefits of a mix of ‘manic’/‘normal’ genes may outweigh the detriments of paired ‘manic’/’manic’ or ‘normal’/normal’.

From my personal experience bosses have noticed that I function very well on focused tasks but do a poor job handling chaotic environments. There are too many distractions for me to focus well and I may be undiagnosed ADD. Flip side, I have found if I can stimulate a portion of my brain with audio then it makes it easier for me to focus on an optical or geometric set of inputs. For comparison purposes I do poorly in the chaos of melee combat which is a spectrum mix of visual and auditory but actually do very well in WOW environments where the visual geometric (characters and terrain) is differentiated from the language (nominally the same brain function as auditory) because they are 2 separate and discrete feeds of input.

I have begun to wonder if those people who have ADD (or ADHD) are experiencing a reinforced combination of genetics (and possibly environmental chemistry) from parents who are good multi-taskers while those who are OCD might be experiencing a reinforced combination of the opposite gene sequence.

Tibor said...


I'm not sure this classifies as multitasking but still - You seem to do quite a lot of things at the same time - writing books (more than one at a time), teaching at a university, giving lectures elsewhere and other things.

I find it really difficult to concentrate on multiple projects at a time. It is not about the immediate concentration like in a melee battle, but more about organization. Now, I'm working on a possible bitcoin business project, I have to (understand and) generalize an article by my Ph.D. advisor, then I'm working on one piece of code for a simulation algorithm, I'm rewriting my diploma thesis into an article with my master thesis advisor and occasionally I'm holding some lectures myself...So far I've only done one thing at a time, but now I feel like I have to do everything all the time which results often in me doing really nothing and instead worrying about what to work on first.

I just wanted to know if you have any tips on how to work on multiple separate things simultaneously. It is not like all of them are due in a week, but since I'm used to more linear (and therefore with closer deadlines) work, I'm not very good at managing this. Any advice is welcome :)

David Friedman said...


I see my tendency to have multiple projects going as part of my not quite ADHD pattern, since when I stop feeling like paying attention to one I can switch to another. As I like to explain to my kids, one way of getting stuff done is to switch to the less unpleasant things that need doing as an excuse to postpone doing the more unpleasant.

Simon said...


I don't know if this is relevant to your situation, but anyway, just in case...

Analyze how much off the worries come from the tasks themselves and how much from fear of not fulfilling the expectations of the people you are working with or for. If there is some of the latter, then I think managing the expectations of your clients or peers can help.

E.g., give early and honest heads-ups when something will be delayed, explain your scheduling constraints, give people frequent enough attention so they don't feel kept in the dark, &c. Most people are tolerant of delays but anxious to know what's going on. A large delay that is announced in advance can give you less trouble than a one-day delay that is unannounced and unexplained. Keeping the people you work with at ease will take some pressure off for you.

Tibor said...

David, Simon:

Thanks for the advice. I also remembered what my master thesis advisor told me. He is a lot into the eastern philosophies and likes to talk about it. It sounded quite funny to me often, but when you translate the metaphors to plain toungue, it contains useful ideas sometimes.

And the problem with me is that I write a list of things to do in a day like "write the article, do the program" and so on...and of course I cannot do all that in a day's work. And then I get frustrated that I did not which cripples my efficiency even more. What he told me is to divide the work to very small segments so that I can actually finish them fast and also focus on a particular problem rather than a broad topic. I've tried it today and it seems to be a better approach.

When I was working on one thing at a time, I did not have to do this since I had only one thing on my list and so nothing distracted me (and still I had common patterns of working on something for 15 hours straight and then doing nothing the next day or two). But now it seems this will lead to better results in a situation where I have to work on more things simultaneously.

Simon: I think it is a lot about the expectations. I feel like I need to finish everything next week (which is often untrue) and then get anxious about it as if I do one thing like that I have no time to go on with the others. But with that new approach it seems to work out better.

Tibor said...

David: A possible problem with your approach is that if there is one thing that is always the most unpleasant, you will never get it done :) But I suppose that condidion does not hold very often if you get things done this way :)

Kevin said...

As a huge David Friedman fan and a gigantic Richard Epstein fan, this post made me unbelievably happy.

Mark in VABeach said...

I've thought that parallel multitasking is only possible when only one task at a time requires thinking. You can drive and have a conversation because driving is pretty autonomous. But if you require thinking on the tasks you are really serially multitasking, although the time period of series of events could be small enough that you may think you are multitasking in parallel. If you can add 2 multi-digit numbers and multiply 2 separate multi-digit numbers at the same time you are parallel multitasker, if not you are a serial multitasker.

Mark in VABeach said...

as another example, if you can simultaneously speak in sign language and with your mouth, saying different things entirely (assuming you know sign language) you are a true multitasker. If you have to do one phrase first in one language and then switch back and forth, you are not.