Pursuit of Truthiness

my gut tells me I know economics

Archive for the ‘Education’ Category

What is Macroeconomics?

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Studying for the comprehensive exam in economics meant wading through a lot of difficult math that still vastly oversimplifies things. It is enough to make anyone wonder, what is the point of it all? This post is my attempt to explain what the point is.  There are a lot of different ways to carve up what a field is, so I will make a brief attempt at several.

End Goal: Most simply, macroeconomics is the study of how to make national economies work well, meaning how to bring about material conditions that make people in general happier.

Intermediate Goals: high GDP growth (more stuff), low unemployment (people who want jobs can get them), and stable prices (a monetary system that facilitates trade). All else equal, these things tend to make people happier, and they are a lot easier to measure than happiness.

Time Frame: We find it useful to divide the field of macroeconomics into growth (long-run) and business cycles (short run), because we think there is little overlap between the best ways to increase long-run growth and the best ways to prevent or reverse sharp declines (recessions). Denying that difference is sometimes seen as denying macroeconomics.

Conclusions: Keynesians think the best way to end recessions is with fiscal policy (government lowering taxes and/or increasing spending).  Monetarists thought we could prevent recessions and high inflation by stabilizing the growth of the money supply; market monetarists now think we can accomplish these goals by stabilizing the expected growth of nominal GDP.  New Classicals think the government can’t really do anything to end recessions.  One can divide macro into many more schools based on such policy conclusions.

History: Recessions in the modern sense (where we have an industrial economy able to recess) begin happening in the early 1800’s, so people begin trying to explain them.  Some like are JS Mill are “under-consumptionists”, saying the economy gets so productive we have trouble consuming all the production or finding useful work for people to do.  Jevons comes up with a sunspot theory, that every 10 years or so sunspots will change the earth’s weather and reduce the productivity of agriculture. A growing thread focuses on the importance of interest rates and money.  The biggest recession of all hit in 1929, leading to the perception that macroeconomics is its own separate crucial field. Governments and public opinion seem to prefer economists who tell them to do something rather than nothing. I can go on with history for a long time, and I haven’t even discussed the history of growth theory, so that is enough for now.

Tools: Often it is not differing goals or conclusions that seperates people but rather the tools they use. Economics began with Adam Smith who was trained as a moral philosopher and whose main tools were eyes to examine the world and a pen to write verbal arguments. David Ricardo turned the profession toward abstract models, looking at a simplified and formalized world about which we can make stronger and more certain statements than we could about the real world in all its complexity. Alfred Marshall brought in graphs and algebra; Jevons and Walras brought calculus. Paul Samuelson showed that most questions in economics could be posed as constrained optimization problems using Lagrangians.  Later economists used the more complex optimization tools of Hamiltonians, dynamic programming and stochastic calculus. Another thread pioneered by Ken Arrow turned up the formalism another notch by using set theory and real analysis; after the 1950’s it is common to speak of theorems and proofs. At any given time some “institutional” or “historical” school is pushing back against the ever-increasing use of math.  Many fear that excess formalism limits the set of questions we think we can answer or even ask. The last great tools-war on the theoretical side is the debate over the use of Dynamic Stochastic General Equilibrium in the 1970’s and 80’s. It is said that many Keynesians objected because they thought the tool would inevitably lead to certain (small-government) conclusions, then stopped objection once it was shown that the tool could be used to support many different conclusions.

There has been a whole separate evolution of tools on the empirical side.  For one thing the quantity and variety of data and the capacity and power of computers has kept expanding. Alongside this has come the gradual development of modern statistics and econometrics.  The many-equation macro models developed in the 1950’s have mostly been displaced by Vector Autoregressions and calibration.

Analogous fields: We have physics envy. We may have succeeded in emulating string theory. The predominant modern paradigm of DSGE uses a mathematical advance to beautifully and elegantly unify of micro, growth, and business-cycle theory.  It also does a poor job of describing the real world.

Stylized facts: Are there any? See jokes.

Jokes: The three scariest words in the English language are “macroeconomists agree that”.  The difference between microeconomics and macroeconomics is that microeconomists are wrong about specific things, while macroeconomists are wrong about things in general.

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Written by James Bailey

February 16, 2012 at 9:23 pm

Berkeley Students Are So Conservative

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They, like most people, are small-c Burkean conservatives about life in general.  They have a strong status quo bias, but rather than admit this like Edmund Burke, they feel compelled to invent reasons why status quo things are good.  Berkeley psychology prof Seth Roberts said “Most of my students, for better or worse, were very conformist. My conclusion…. is that the reasons we give for our beliefs have roughly zero correlation with the actual reasons and shouldn’t be taken seriously (e.g., argued with).”  Robin Hanson said the same about George Mason students:

  • Ask random colleges student random policy questions and they will feel compelled to come up with opinions.
  • Ask them for reasons for those opinions and they’ll feel compelled to come up with such reasons.
  • Such opinions strongly tend to support the status quo – mostly whatever is, is assumed good.
I am thinking along similar lines today after discussing organ markets with my students.  Students say that legal markets in human organs would be bad mainly because it would lead to organ theft.  Even supposing there would be more organ thefts, it is hard to imagine there would be enough to outweigh the deaths of 9000 Americans every year caused by our current ban on organ sales.  If people were used to a functioning market in organs, I have to think they would be horrified by someone saying we should ban organ sales and consign thousands to death in order to reduce theft, just as it would seem crazy to ban day-laboring to protect laborers from employers who stiff them after a day’s work (stealing is already illegal!).  It is easier to think there must be a good reason for the status quo, that we live in the best of all possible worlds and aren’t doing something horrible.  Indeed, there is more right with the world than wrong with it; there is a reason status-quo-biased people continue to survive and thrive.  Further, it is dangerous to think that those who disagree with you must do so out of some ignorant bias; call this the “bias bias”.
In general though, if we are trying to figure out the truth, we have to fight pro-status-quo bias more often than its opposite.  The reason for this is wired into our brains: our dominant trait is to rationalize, not reason.  One part of our brain is dedicated to coming up with a reason for anything, whether it makes sense or not.  In extreme cases, paralyzed people can come up with all sorts of reasons to explain why they aren’t really paralyzed; their brain is acting as an apologist for what is done, not a reasoned truth-seeker (Seriously, check out that link- it is way more interesting than my post, even if you have heard of the phenomenon before).
I am optimistic about getting people who think of themselves as non-conformist or politically liberal to consider new ideas by telling them they are being conservative conformists.  Put name-calling to good use!

Written by James Bailey

October 17, 2011 at 3:00 pm

It’s a Liquidity Trap!

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I’m not proud of this, but its seems no one in the whole wide internets had done it yet, and it needed to be done:

Ackbar realizes he's trying to push on a string

The best part is that our solution to the liquidity TRAP was a TARP.  Now let’s hear the Bernanke/Ackbar jokes.

Written by James Bailey

February 16, 2010 at 11:30 am

College Taught Me How to Vote (sometimes)

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As I filled out my absentee ballot, I found myself deeply ambivalent- both about the local races I know nothing about, and the Presidential race I’ve been reading about for months and could talk about for hours.  I wonder whether all these things I know about the candidates reflect what they know about themselves and their real plans; and further how future events will intervene to make the candidates act in ways they themselves don’t anticipate.

But the problem is bigger than uncertainty about the future; it is more a fundamental inability to judge people.  I lack the experience, knowledge, and confidence to say that one person is better than another unless the evidence is overwhelming.  College taught me how to evaluate position papers and speeches, but some time working HR, or working anywhere, would have taught me to evaluate people with more confidence (if not knowledge).

So why do I say that college taught me how to vote, if it left me unable to choose candidates?  Easy, there’s more than names on a ballot!  There are questions, direct questions about single issues.  That’s exactly the kind of thing college is good for; these questions could blend into an exam in political science, philosophy, or economics.  Except they’re easy; it is pretty straightforward to see which groups are hurt or helped economically, and how a single proposition fits with your political philosophy.

The ironic part of all this single-issue preparation is that while I feel I’ve learned well how to vote as a senator, I’m left clueless about how to vote for a senator.

Written by James Bailey

November 3, 2008 at 2:28 am

2,4,6,8, who do we indoctrinate?

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Our Children! Go Maine!

Written by James Bailey

June 16, 2007 at 9:06 pm