Monthly Archives: July 2007

Fridge advice?

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Here’s a shout out. Our fridge is misbehaving. It’s an Amana, with the freezer on the bottom. The freezer is working fine. The top has stopped working. Anybody got a theory on how that’s possible?

Update: I took it apart. There is a fan in the bottom freezer that circulates cold air. Included in that circulation is the run of air that chills the upper part. The fan isn’t working. I removed it and tested it. Of course it worked; but it also behaves in a manner that suggests it’s variable speed and has a thermostat. So I suspect I need to replace it. I put it all back together and it worked until we finished cleaning it; then it stopped.

Update 2: Disassembled again, the bearing in the fan motor is worn out. Once you know this thing is called an evaporator fan you can find some pretty good sites showing how the fridge is put together. More delightfully I found pdf containing a scan of the typewritten paper outlining the design. It was written in 1978 by some engineers at Amana in Iowa and the work was funded by the US government in service of making appliances more efficient. It looks to me like the design is unchanged in almost 30 years. Now to find the part, locally, on a Saturday.

Update 3: New fan: $80.  Installed, everything works – yeah. Oh boy, it’s really quiet!  20 minutes later it stops – boo.  A while later – it works – yeah?  24 hours later it all seems pretty good; and i think the random stopping is part of a defrost cycle.  Reading what I refer to as my handbook for obsessive compulsives I learn that the freezer should be around zero degree’s F, and the upper part should be around 36 degrees.  So far I’ve managed to get the top right, and the bottom’s 10 degrees too cold.  It’s now clear we should have sensed trouble when: it got noisy, the beer started getting warm, and the lettuce started freezing.

Bus Driver’s guide to Project Management

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I take the bus to work most every day and recently I’ve noticed two new, to me, syndromes.  First off I’ve noticed that I catch later of two morning buses it will passes the earlier bus on it’s way.  Secondly I’ve noticed  that if the bus is even a few seconds ahead of schedule this advantage will  accumulate so that it arives at the train station quite a bit ahead of schedule. Both of these have to do with passenger loading delays.

The 2nd bus wins because it is less popular, so it stops less often; while the 1st bus is very popular and has to stop a lot.  It’s the passengers,  and their loading time.

The second syndrome, where the amount a bus is running ahead of schedule piles up is also due to the passengers.  In this case the bus doesn’t have to pickup passengers who come out to the bus stop on schedule.  I’ve noticed that when I miss my favorite bus, but I’m on schedule, it will drive by empty – which of of course get’s my goat.

These are interesting complementary syndromes and they suggest that being on schedule is unstable.  Early buses tend to become even earlier, since the load they usually carry doesn’t appear; while buses that run late tend to accumulate additional loading costs.  It’s fun to think about how one might overlay some regulatory scheme to temper these effects.

Seems to me there is an analagous syndrome in projects.  Delayed projects tend to accumulate more items, as the delays allow more requirements to show up and pile-on.  Projects ahead of schedule tend to pick up speed as they drive pass additional requirements which haven’t managed to get the meetings on time.

It’s interesting to muse about what interventions one might take in these situations.  Driving by a few bus stops to get back on schedule, or explicitly ignoring a few project requriments is very hard to execute on.  There is one bus driver on my route who appears to have discovered that he can spend a lot more time drinking coffee if he gets ahead of schedule; the man’s a maniac.  I’ve worked with managers like that.

The Road Less Traveled

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I’ve read that given two stores people will tend to visit the one that is toward the city center in preference to the one that’s in the other direction.  It’s as if you had to climb uphill to move away from the city center.  Customers tend to flow, like water toward the commercial centers.

These effects get filled under the term Hoteling in some of the economics’s literature.  In it’s most naive form Hoteling is kind of stupid; it merely points out that buyers include the total cost of a transaction when making a purchase.  The vegetables maybe spectacular at Russo’s or dirt cheap at Haymarket; both a half hour round trip from my house; but the Foodmaster  at the bottom of my street is a damn sight more convenient.  Which goes to explain why there are a few dozen Foodmaster’s around town; like a hotel chain Mr. Foodmaster knows that part of what he’s selling is being close at hand.

My reading on hyperbolic discounting suggests that hoteling effects are much stronger than mere arithmetic would suggest.  I suspect that people have extremely skewed models about this stuff.  The hills are much steeper than it’s possible to imagine.  That most people shop closer to home and stick to the main roads far more than would be in their best interest.

I’ve always been a road less traveled kind of guy.  As a child, before first grade, I can recall lying in bed tracing out the roads of my town; wondering what was down particular turns my parents had never taken.  As an adult I have a self amused tendency to take turns out of raw curiosity and a strong preference for taking the roads the super highways replaced.  I know that the interesting authentic vendors tend to be hidden, around the corner, up the stairs, where their unique qualities sustain them; rather than their proximity to traffic.

Hoteling effects, of course, take place in your mind too.  When something new needs an explanation you fall naturally into the existing explanations.  When you must decide what to do your thoughts flow into existing channels.  It would be, it is, exhausting not to.

In this country, where we have traditionally had tremendous amounts of empty real estate, we have undergone waves of upheaval that have transformed the shape of the traffic flows.  We have successively overlaid networks of rivers, turnpikes, canals, railroads, and superhighways.  For better or worse, each time these have created new commercial centers while displacing older ones.

In each round some people got really rich.  Not by buying the land cheap and selling it high, but by shaping the traffic flows until they came to the land they owned.    Some railroad barons are and were more conscious of this process than others.  For example the folks building Facebook are clearly working hard to see that social traffic flows over their turnpikes.

As a guy who like to take the road less traveled I’m pleased to see that Google Maps has added little handles to their suggested routes that enable me to dynamically drag them.  Now I can insist that, yes I do want to drive thru downtown on this trip; and yes I do want to make detour that goes along the beach road, and yes I do want to cross the river on that exceptionally narrow bridge.  But I wonder, why did they decide that such a feature would actually be interesting to most people?  Most people aren’t like me.  I suspect I’m way out on the long tail of map users; but then I suspect the folks working on Google maps are too.