The Null Hypothesis and Online Education

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Bradford S. Bell and Jessica E. Federman write,

The meta-analyses reviewed above show that when instructional design characteristics are held constant across delivery conditions, e-learning and classroom instruction generally produce similar learning outcomes.

Pointer from Timothy Taylor–read his whole post.

The null hypothesis is that there is no difference in outcomes, and apparently the “meta analysis” does not reject the null hypothesis. Taylor interprets this as evidence that online learning has “caught up” to classroom learning in terms of quality. My more cynical interpretation is that there was never any catching up required, because what students learn does not appear to depend in any way on how they are taught. I am sure that there is a limit to this: presumably, if you do a randomized experiment in which one group of students gets $50,000 worth of instruction and another group gets zero, you will see some difference in outcomes. However, I would bet that, relative to what we do today, the way to improve cost-effectiveness in education is to slash costs. That is, my view of the null hypothesis is that most of what we spend on education has no marginal impact.

Note, however, that the authors of the study seem convinced that the null hypothesis is false. They believe that empirical evidence shows that pedagogical techniques do affect outcomes.

Manzi on the Oregon Medicaid Study

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Russ Roberts draws him out. Much of the focus is on the fact that almost half of the people who won the lottery to obtain Medicaid coverage then did not apply.

What that means, Manzi suggests, is that the group of people who obtained Medicaid coverage, rather than blow it off, may have been different from the control group that lost the lottery. That is, you don’t have two groups–winners and losers. You have three groups–losers of the lottery, winners who took coverage, and winners who did not take coverage. Manzi is saying that one cannot be sure that the winners who took coverage are comparable to the losers, which makes the results difficult to interpret.

Previously, Russ interviewed Austin Frakt on the study.

Peter Thiel Wants a Rat Thing

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Look at what Peter Thiel is investing in:

Over the past six years RoboteX has developed a lineup of sturdy robots versatile enough to be used by the military, police, or people who think they might have heard something in the shed. Their Avatar series Security Robot goes on patrol so humans don’t have to. Realtime video is fed to a control center wirelessly for monitoring, and a two-way audio feed allows controllers to ask questions first and get answers hundreds of miles away. Its camera has full 360 degree coverage and shoots in both visual and infrared – so there’s no hiding in the dark. It’s also hard to get away from – capable of climbing stairs and moving over carpets, wet floors, even rugged outdoor terrain

It reminds me of the Rat Thing, one of my favorite elements in Neal Stephenson’s Snow Crash. If people believe that they can address their own safety issues without government, that becomes a big deal.

Vacation in Croatia and Slovenia

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That is where I was for most of the latter part of May. A few notes:

1. Travel in the Internet age is amazing. An interesting question is which countries/regions/towns will benefit most as travel becomes easier and more affordable. We only stayed in one legitimate hotel, but all of our accommodations were clean, comfortable, friendly, and well-run. We put over 1000 miles on a car. I did not bring my computer, but Internet access was easier than it is when you travel in the U.S. Free WiFi seemed to be everywhere. We did not use any tour group or travel agent. We relied on friends. One friend was “Rick,” meaning the guidebook written by Rick Steves. Another friend was tripadvisor.com, which we used to double-check (and occasionally override) Rick. Another friend was “Bonnie,” our English-speaking navigation system in the rental car from British firm Sixt. Bonnie did not always choose the most obvious routes. Once, when we were trying to connect up with a major highway, she took us down a narrow lane through a vineyard that dumped us onto a road that indeed took us to the freeway entrance. Another time, however, she kept trying to get us to the highway using a route that simply was not operable, and we had to ask for directions.

2. Another interesting question is what happens if/when English loses its dominant role as everybody’s second language. In a place like Croatia or Slovenia, we see that Russians, Germans and Asians have to speak English in order to communicate with one another and with locals. But the presence of native-speaking English tourists is relatively low (more Brits than Americans). What if China becomes the largest source of tourist revenue? What if translation apps on cell phones become good enough to enable one to order a meal, register for a hotel, ask someone to take a picture, or ask for directions in any language?

3. Yet another question is what is the optimum currency area? I think that many economists nowadays doubt that the eurozone is an optimum currency area. But is Croatia? In any event, the dollar has lost its role as tourism’s medium of exchange or unit of account. Do not expect to get anywhere by offering to pay using greenbacks. In Bosnia, Montenegro, and Slovenia, you transact in euro. Croatia has its own currency, but prices for tourists are often quoted in euro. Given the importance of tourism, should all these countries simply adopt the euro?

4. On the European Union (Slovenia is in, and Croatia is in any day now), we had a very small sample of opinion (one person in each country) . Our sample thought that being in the European Union was more likely to inhibit trade than to help it. For example, Bosnian farm exports to Croatia will now be subject to costly regulation. Our sample also did not like the undemocratic nature of EU policy-making. Our sample complained of being “sold down the river by our politicians.”

5. It is very sobering to realize that this region was torn apart by war just two decades ago. What does the bitter post-Tito breakup of Yugoslavia tell us about, say, Mark Weiner’s thesis? Arguably, NATO replaced Tito as the hegemon required to keep the lid on ethnic hatreds.

6. Now that they are separate states, at least some of the countries are thriving, but I can imagine them doing better with more integration. If one could get the ethnic groups to remain peaceful with one another and at the same time avoid excessively statist economic policies, I imagine they would have to better off if they were federated in some way. If nothing else, it would get rid of a lot of wasteful border crossings. However, given the historical reality, perhaps the Balkans are better off…Balkanized. Continue reading →

Robin Hanson on Clans

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He writes,

In most farmer-era cultures extended families, or clans, were the main unit of social organization, for production, marriage, politics, war, law, and insurance. People trusted their clans, but not outsiders, and felt little obligation to treat outsiders fairly. Our industrial economy, in contrast, relies on our trusting and playing fair in new kinds of organizations: firms, cities, and nations, and on our changing our activities and locations to support them.

Read the whole post.

The Tea Party vs. The Common Core

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It is the lead story in today’s Washington Post.

Lawmakers have responded by introducing legislation that would at least temporarily block the standards in at least nine states, including two that have put the program on hold. The Republican governors of Indiana and Pennsylvania quickly agreed to pause Common Core, and Michigan Gov. Rick Snyder (R), a vocal supporter of the plan, is nevertheless expected to accept a budget agreement struck by GOP legislators that would withhold funding for the program pending further debate.

I strongly support the Tea Party on this one. I was an early opponent of national testing. Ten years ago, I wrote

For the standardized testing approach to accountability, success by definition means making schools responsive to top-down control. In the case of the Bush administration “reforms,” standardized testing increases the leverage of the Federal government over local schools. Any conservative ought to think twice about supporting such a trend.

Schools Suffer From Regulatory Arbitrage

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At the WSJ blog, Michael Derby writes,

The way some schools are being held to account for student performance can corrupt how these institutions seek to achieve the standards, a new paper from the Federal Reserve Bank of New York warns.

In other news, the way banks are being held to risk-based capital standards can corrupt how banks seek to achieve the standards, according to a new paper from researchers at the department of education.

Freddie, Fannie Profits

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The Washington Post reported (a few weeks ago) that Fannie Mae has made large profits that will go to the U.S. Treasury.

I expect these profits to continue, because the business model right now is excellent. The government is saying to mortgage originators:

1. Do not originate any loans that do not comply with our rules.

2. We cannot tell you what the rules are yet, because they are not final (it’s only been, what, 3 years since Dodd-Frank passed?)

3. But Freddie and Fannie have an exemption, so anything they will take you can originate and we won’t bother you.

Freddie and Fannie do not have to worry much about credit risk, because the housing market bottomed out a while ago, so we are unlikely to see another house price collapse.

Freddie and Fannie are borrowing at Treasury rates, so they enjoy a nice, juicy margin. And the Fed is still holding onto a lot of mortgage securities, which helps keep their prices up.

The one fly in the ointment is that Freddie and Fannie probably are exposing taxpayers to more interest-rate risk. That is, all those 4 percent mortgages that the government is holding on our behalf will not look so profitable if the Treasury’s cost of borrowing should go up to, say, 6 percent. That is already the worst possible scenario from a government solvency standpoint. In that sense, from a taxpayer point of view, Freddie and Fannie are risk-aggravating. Meanwhile, enjoy the windfall.

James Hamilton points out that another fly in the ointment is that a lot of Fannie’s profits are actually tax deductions that come at the expense of the Treasury.

Productivity Measurement Pessimism

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Timothy Taylor reports on a symposium on productivity trends. He quotes Robert Gordon,

I have often posed the following set of choices. Option A is to keep everything invented up until ten years ago, including laptops, Google, Amazon, and Wikipedia, while also keeping running water and indoor toilets. Option B is to keep everything invented up until yesterday, including Facebook, iphones, and ipads, but give up running water and indoor toilets; one must go outside to take care of one’s needs; one must carry all the water for cooking, cleaning, and bathing in buckets and pails. Often audiences laugh when confronted with the choice between A and B, because the answer seems so obvious.

I think that what this anecdote indicates is that measured productivity is bunk. Gordon’s anecdote suggests that people derive a lot of consumers’ surplus from modern water systems. But this consumers’ surplus does not show up in measures of productivity, either for one hundred years ago or for today.

I am becoming a productivity measurement pessimist. That is, I am becoming pessimistic that what we call “productivity” is anything more than a crude indicator of trends in living standards.

I can imagine coming up with an accurate measure of productivity in soybean output. However, it is difficult to imagine coming up with anything accurate for health care, where we have little idea about what generates value at the margin, or for education, we where have almost no idea at all.

Moreover, the value of many goods and services, including the Internet and modern water systems, is under-estimated because we do not measure consumers’ surplus. Going forward, suppose that researchers come up with a way to prevent or cure Alzheimer’s. The effect on consumers’ surplus would be quite large. The effect on measured productivity? To a first approximation, nil.

In assessing economic progress, productivity may be the best indicator we have. However, we take small differences in measured productivity growth rates way too seriously. On the one hand, it is correct to say that if you extrapolate a difference in productivity growth of 1 or 2 percentage points over thirty years, it accumulates to a big number. But I fear that it is quite possible that the error in measuring productivity growth can exceed 1 or 2 percentage points for thirty years or more. That is, I think it is quite possible to take two thirty-year periods and arrive at a very large estimate of the difference in the rate of growth of living standards that is entirely due to mis-measurement.

Anarchism

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From Kelefa Sanneh in the New Yorker.

Rothbard was an anarchist, but also a capitalist. “True anarchism will be capitalism, and true capitalism will be anarchism,” he once said, and he sometimes referred to himself by means of a seven-syllable honorific: “anarcho-capitalist.” Graeber thinks that governments treat their citizens “like children,” and that, when governments disappear, people will behave differently. Anarcho-capitalists, on the contrary, believe that, without government, people will behave more or less the same: we will be just as creative or greedy or competent as we are now, only freer. Instead of imagining a world without drastic inequality, anarcho-capitalists imagine a world where people and their property are secured by private defense agencies, which are paid to keep the peace. Graeber doesn’t consider anarcho-capitalists to be true anarchists; no doubt the feeling is mutual.

The article is a profile of David Graeber, an anthropologist who got involved with the Occupy movement.