Time-money convertiblity

While reading Robin Hanson's recent post on why bets aren't used more often to back up people's beliefs, I was struck by one of his followup comments, the gist of which is that people shouldn't waste their time arguing because they could be using that time to earn more money. Leaving aside the argument that dialog, discourse, and argument are at the very least methods of refining ideas and beliefs and therefor have value, this argument about time and money has always struck me as a bad model.

There is a large class of people for whom time cannot generally be converted to money. For some people like me, their terms of employment forbid outside work. These salaried people are paid not by the hour but a fixed sum to do their work no matter how long it takes. For me that generally means that I'm working more than 40 hours a week as well. So not only do I not have the time and energy for more work, but I can't do it anyway.

Many (most?) hourly employees also cannot work more hours to get more pay either. Full-time workers are generally forbidden overtime without explicit approval. They are required to get their work done in the allotted time and either do not work overtime or are (illegally) forbidden to report it. Either way, without a second job, they cannot supplement their incomes by working an extra hour.

Given that, we're left with a group of people that are able to choose between a second job and an hour of fighting over ideas. The cost of finding a second job for an additional hour of pay seems to be much higher than foregoing that pay in order to have an argument. Perhaps Mechanical Turk has a lower barrier to getting started, but the pay doesn't really seem worth it for many workers.

I see this argument pretty frequently, but I don't really think it holds water. For most workers the value of an additional hour of work falls off a cliff around 40 hours per week and for most job types so does the worker's productivity. Modeling pay as a linear function of hours work just doesn't cut it.

Also, spend your out of work time how you want.

Leipzig, day 1

My hotel is directly across from the Universitat Leipzig. Down the road  a a short walk across Augustus Platz and through a shopping disict is the Auerbachs Keller where Goethe staged his famous debate. I'm sitting there now. I was expecting more beer hall than big dining room, but I think I'll be OK. They have a few beers on tap, and I'm trying what I think is going to be wild boar sausage with sides. Specifically: Wildschweinbraten MIT Pilzfrikassee, Rotkohl, rohen Kartoffelklossen, und Kroketten. I'm having the Ur-Krostitzer dark to drink. 

The travel getting here was a little convoluted. Flights into Leipzig were completely full, Frankfurt, too, so some of my colleagues and I flew into Dusseldorf and took some trains. The fast train from Dusseldorf to Hanover was excellent. We changed inHanover to a regular intercity train headed for Leipzing, but learned that we'd have to change in Magdeberg to a local train to go around the flooding further down the line. The Hanover train was old and hot, but the local was brand new and appropriately cooled. 

The beer, having arrived, is smooth and dark brown with a fine foam and thickish mouthfeel. Vey malty and a little sour. Very tasty. 

Of course, braten means braised, and so I have a braised saddle of wild boar with mushrooms which is fantastic. The red cabbage and beet sauerkraut is a great accompaniment, the croquettes are tasty, and there's a spongy sphere of I know not what (it's dumpling). 

My newest favorite phrases

Dunning-Krugerand

Helicopter Gunship Parents

New House Notes

We're in the new house now. There's a few things in the old house still to be gotten rid of and the repairs to do before we can sell, but we're out!

Many thanks to R.D. (son of a Master Electrician) for help rewiring the dryer from 3-prong to 4-prong. The electrical work was straightforward, but he was watching and giving good, sound advice the whole time, especially about flipping the outlet over when the cord wouldn't reach. Also, moving a stacked washer and dryer is much easier (read possible) with two people.

I've got to learn a new way to get to work. We only moved a dozen blocks, but finding an optimal way in is going to be tricky. If I hit the northbound train at Lamar and Airport, I'm guaranteed to hit it again at 183 just before Burnet. Going over to Burnet first would save that hassle, but I think it's far enough out of the way that going up Lamar is a better choice. I'll have to do some more experimentation and research. Google definitely thinks I should take Burnet, but what do they know?

Speaking of efficiency, and first world problems, I've got to learn to move around my new kitchen efficiently. I don't always know where everything is, and things are much further apart now. It's going to require some route planning to efficiently use.

Today I drew.

To follow up on last Thursday's post, today I drew an electronic version of the picture I'd been drawing on whiteboards around the office at the end of the week. I suspect this will appear in a talk about MICs some time soon.

Today I Learned.

And, I actually prefer it that way.

I relearned the lesson of Amdahl's Law, and I learned a new word, "bathetic". No, I didn't spell that wrong. Bathetic, with a 'B'. Which, in a similar but not exactly the same vein as 'pathetic', draws on the Greek word 'bathos' meaning depth. But what it really means is an abrupt, absurd fall into mediocrity or chaos.

The basic lesson of Amdahl's Law is that parallel computing is hard. The slightly more than basic lesson is that adding additional simultaneous processing to a problem only helps in so far as there is simultaneity to be had.  Which is to say that if half of your work is completely serial and half is completely parallelizable, you can only expect to halve your run time with all the additional processors in the universe.

Today's lesson from Amdahl takes a bit of a jag. If the gods give you a magic computer that does the parallel portion of your calculation infinitely fast, effectively reducing its run time to zero, but it runs the serial portions of your code slower, then you should think carefully before making promises about what that gift can do. Even if this computer instantly returns the result of the parallel part, if it also doubles the run time of the serial part of the code, then the gift is a wash if half the work is serial and half the work is parallel. Fortunately, in the real world, the best scientists build codes where more than 99.999% of the work is parallelizable.

Unfortunately, this is, in some ways, the problem with GPUs, Xeon Phis, FPGAs, and other computing accelerators. They do some things extremely well, and while they don't reduce the parallel run times to zero, they may cut them by significant factors. But to do this, they have to sacrifice performance on serial execution. If you don't watch out for this, you can get killed by it, bathetically.

Great video from NASA's SDO satellite. (HT: /.)