Monday, April 14, 2014

5 Flaws of "Cosmos"

This post by Hank Campbell at "The Federalist" blog suggests 5 myths in the Neil Degrasse Tyson's remake of the Carl Sagan's "Cosmos". I admit that Mr. Campbell may know more about the scientific validity of the claims put forth in the series (or perhaps not - it does not appear Mr. Campbell has any specialized training in physics or astronomy), but in some ways he comes off a little to harshly in the opposite direction. Here are the flaws Campbell points out:
1. Venus Was Not Caused By Global Warming
Perhaps he is right here. There are probably several factors that make Venus' average temperature consistently around 860 degrees Fahrenheit, but Mr. Campbell doesn't explain what REALLY might make Venus that hot, and it's not simply proximity to the sun: Mercury is about the same temperature as Venus on its sun-facing side, but reaches extremes of about -800 degrees on its dark side. Probably it is a combination of factors, but something has to be at work keeping the dark side of Venus at a temperature as remarkably close to the sunny side as we have observed. Atmospheric gasses play an important role (if it weren't for the green house effect we'd all freeze by the way!).
2. The Multiverse Is Not Science
In a narrow definition of science, this is a true statement. Multiverse theory is not fully testable because seeing beyond the "horizon" of the observable universe (and yes, I know the universe doesn't have a "horizon" per se).That doesn't make it non-science. Scientists who "believe" in a multiverse derive their models of the multiverse from models that must follow physical laws we have observed in tests of other hypotheses about the big bang. In fact, the recent discovery of gravitational waves near the universe's origins, which also supported "inflation theory", increased the likelihood that a multiverse is possible.
3. There Is No Sound In Space
Ok. Sure.
4. Giordano Bruno Was Not More Important To Science Than Kepler And Galileo
Yeah, I kinda hated that part, too.
5. The Universe Was Also Not Created In One Year
As Campbell admits, this is mostly a style issue. It's meant to be a device for understanding the vastness of time. Apparently it didn't work on the founder of Science 2.0. But here is my beef with this point. Campbell states:
Rather than seeking to take jabs at religion, science should be embracing it. From a science perspective, religious people are involved in the largest ongoing experiment of all time. The major religions all disagree with each other in ways large and small and yet people are turning knobs in their lives and making adjustments to try and solve a grand mystery. What, if anything, comes next?
Whoa. I don't really see religious or areligious people as being any more or less in the struggle to understand the meaning of existence, or what comes after the life we know than the other. Much of this depends more on the individual. An atheist who adamantly believes that death is the end is no less at struggle with that grand mystery than someone who adamantly believes we will all be swept up to heaven or hell depending on our deeds and on our faith. I'm agonstic, and believe you me, Mr. Campbell, I spend much of my time turning knobs trying to figure out what's in store for me when my body's strength is gone.

Thursday, April 10, 2014

Framing Effects and Student Evaluations

It's student evaluation season, which always puts me in a sunny mood. While there are some studies that apparently refute the hypothesis that leniency buys better evaluations, there are reasons to be suspicious of the validity of these OLS results. For example, in hard departments like science and engineering, someone is going to appear to be better than the others, and it is hard to control for individual characteristics of the students in anonomized surveys that can't be matched up to the observable characteristics about those individuals. But I digress...
One thing that strikes me as an interesting hypothesis is to test what would happen to teaching evaluations by changing the sequencing of the questions. For example, in the forms I will administer next week, (the "Student Instructional Report II, or SIRII) the very last questions before the overall evaluation ask students about their effort and the course's difficulty. If behavioral economics teaches us something, it's that framing (or maybe this is anchoring?) matters in survey design. It seems like a neat workaround to test the "leniency hypothesis" would be to change the order of the question so that effort and difficulty are randomly asked their overall evalution either before or after the difficulty and effort questions.

Tuesday, April 1, 2014

Coming to Econ from Econ

Noah Smith writes this post on the advantages and disadvantages of coming to an econ graduate program from a physics undergraduate major. The upshot: It helps a little and it hurts a little. The same can be said for coming to econ from econ.
The big advantage doing econ from undergrad all the way through is that when you get to grad school you already speak the language and know the intuition - at least on the micro side of things.
There are two potential disadvantages to coming to this path. First, if you're like me, your undergraduate focused on policy economics, and you learned about things like  IS-LM, fiscal policy, and monetary policy on the macro side; and public goods, externalities, and other market failures on the micro side. This knowledge will not help you survive the core micro or macro sequence in grad school. In fact, it will likely hurt you (especially in the macro side).
The other disadvantage is not enough math. If you're like me you took a few semesters of calculus, some stats, an econometrics course, and maybe even a decent math econ class and thought you were hot shit. What do you win for all that? A rude effing awakening when  you get to grad school. If you do econ, pair it with a math and/or stats minor, at least - maybe even a double major.

Thursday, September 26, 2013

Reverse Causality

The headline "Does the value of driving differ across states?" seems to imply that driving more causes higher incomes. Couldn't it very well be the opposite? Higher GDPs per capita lead to higher population densities, higher congestion, higher property values where jobs are, and hence more total miles driven?

Friday, August 23, 2013

Distortions, Taxes, Absurdity, and What they can Teach Us about Tyler Cowen

Recently, Professor Cowen made the post, "I am sorry but this is absurd" in response to an article by Charles Manski, summarized on VOXEU. The crux of the paper, and of the summary, is that too much analysis of taxation focuses on the various distortions they create, and too little of the analysis goes towards what the tax revenues are used for (infrastructure, in the complete version of the research). How I feel about this issue is not the topic of my post. Instead I choose to focus on Professor Cowen's response to it, and what it really teaches us.
1. I do not believe that Professor Cowen is truly sorry for saying Professor Manski's article (and post in VOXEU) is absurd. I think that at best Professor Cowen has what he might call "meta-preference" for feeling sorry, because he thinks that he "should" feel sorry for posting such an unprofessional and unthoughtful headline to his response to Manski, but I don't think he is in fact sorry. The reason is that if you read Cowen's post, it is quite long, and in fact contains some intelligent and well thought-out points, which to me shows that he has carefully thought about how he feels about the issue.
2. I think the statement "this is absurd" tells us more about Cowen than it does about the piece by Manski. I do not mean this to be turning the term "absurd" on Cowen's view, because I think the details of his post have some merit. Rather I think his use of "absurd" mostly tells us that Cowen feels very strongly that taxes are distortionary and that this should be a topic of focus when economists discuss them. This view has some merit, but it fails to recognize that the alternative to a market "distorted" by government and taxes is seldom a free and well-functioning market in the neoclassical sense. Focusing on the distortions of taxes and government do a poor job of recognizing the ways in which a well functioning (even if also very large) government can help to make property rights more secure and reduce the transactions costs and risks associated with impersonal market exchange. Higher taxes can introduce some distortions, but they may be better than the distortions introduced under the next-best (institutional) alternative.