Friday, February 28, 2014

The Senate immigration bill is not dead

My facebook/google profile picture is a screen capture from a Fox News interview I did on the Senate immigration bill, from May 7th of last year. I thought I'd share it to warn people that immigration is still a live issue, as the House ponders whether to pass a similar "reform."

The video takes about ten seconds to load, and it contains an annoying commercial from Fox that I can't get rid of. So please be patient.


If the embedded video isn't working, you can watch it here.

Sunday, February 23, 2014

Against "consensus" science

I often cringe when I hear the media use the word consensus in reference to some area of science. The concept of consensus is antithetical to the scientific method. I have no problem talking about "mainstream" or "conventional" science, or saying that "most scholars accept" some claim. But "consensus" is not right.

Much like the equally bad phrase "settled science," consensus implies that the debate is entirely over. That indisputable proof exists. That anyone who disagrees is simply wrong as a matter of objective fact. Worst of all, it implies that truth can be determined by a majority vote.

Who believes in gravity?

In science, nothing is ever final. Everything is constantly subject to re-evaluation and re-testing. In fact, if a statement is not falsifiable, then it's not considered a scientific claim in the first place. And it takes only one person--not a majority--to overturn an existing finding.

"But wait a minute, Jason," every reader is surely now saying. "Didn't you use the term consensus to describe the foundations of IQ research?" Guilty as charged, but that was actually a calculated appeal to the journalists who formed my target audience. The reference is in "Why can't we talk about IQ?" published by Politico. (Of all my responses to the dissertation controversy from eight months ago, that's the one I am most proud of.) To show that the media had denounced scientific findings about which there is little technical dispute, I wrote:
What scholars of mental ability know, but have never successfully gotten the media to understand, is that a scientific consensus, based on an extensive and consistent literature, has long been reached on many of the questions that still seem controversial to journalists. [emphasis added]
I went back and forth on whether to use the word consensus to describe that set of views shared by nearly all cognitive psychologists. In the end I went with it, because the word carries a certain resonance with my intended audience. It was an appeal to those on the Left who are accustomed to hearing consensus thrown around in the context of global warming, second-hand smoke, same-sex parenting, and so on.

I wanted Politico readers to consider that they might be just as wrong about IQ as they believe their opponents are about those other issues. So I deliberately used "consensus" rather than "mainstream" or "rarely disputed."

Anyway, this whole post was motivated by the alleged consensus on government preschool, which I discussed in National Review recently.

Monday, February 10, 2014

Roundup of recent preschool commentary

My long-form article ("Pre-K Decay") in the current print version of National Review follows a series of shorter pieces on preschool that I've written in the last few months.

"Does Government Preschool Add Value? Probably Not" makes the point that a government preschool program should offer "value added" rather than just substitute for the early education that children are already receiving through private providers or their parents. A randomized experiment properly measures value added, while regression discontinuity design (a popular non-experimental method) does not.

"Public Pre-K Defenders’ Latest Excuse: If Only Elementary Schools Weren’t So Bad..." takes on a common defense of government preschool. Preschool "works," according to this view, but the gains fade out due to the poor performance of elementary schools that children go on to attend. The trouble is that no one knows how to reliably and substantially improve K-12 schooling, and--even if we did--it would not necessarily make preschool any more valuable.

"Can de Blasio Look to New Jersey’s Pre-K Success? The Evidence Is Weak" details the problem of self-selection bias that plagues non-experimental preschool studies. New Jersey's preschool program for its "Abbot districts" is hailed as a great success, but the evidence is based on a simple matching exercise that cannot adequately deal with selection bias.

Friday, February 7, 2014

"Pre-K decay" in February 24th issue of National Review

Read pp. 21-22 !
I have an article in the print version of National Review that brings together a lot of the points I've been making about government preschool over the past few months. "Pre-K Decay"--I don't come up with the titles, all right?--describes how preschool advocates have persistently exaggerated the empirical evidence that underlies their movement. They are utterly confident that preschool is effective, but their arguments from the data require hope and speculation:
That’s the strange thing about the preschool movement. It mixes scholarship and advocacy in a way that leads some academics to put themselves far out in front of what the evidence supports. Preschool advocates inundate their audiences with long and authoritative-looking lists of academic citations, but they rarely seem troubled by the rigorous gold-standard evaluations that generate contrary results. Healthy skepticism—which is crucial to a good scholarly mindset—is too often absent among the preschool movement’s most vocal leaders.
Download a pdf of the article here.

Wednesday, February 5, 2014

Keepers of the conventional-wisdom flame

When a sufficient number of thought leaders endorse some nugget of conventional wisdom, that wisdom becomes seemingly impossible to knock down. Even with contrary data and evidence at hand, the conventional-wisdom flame burns on and on.
One of those nuggets is what Eric Hanushek calls "input-based schooling policy." It's the idea that public schools can be improved with more inputs: more teachers, more administrators, more licenses, more certifications, more classrooms, more textbooks, more computers, and more and more and more spending.

Although there is little empirical support for the input model--see the link above--it's still regarded in non-expert circles as a matter of plain common sense. I have an example of this from an unlikely place: The Onion. We can learn a lot about what people think based on the jokes they tell, and in that sense the Onion is a big, shining reflection of conventional wisdom within the intellectual class.

Here's a 2011 Onion article: "Budget Mix-Up Provides Nation's Schools With Enough Money To Properly Educate Students." It's fairly funny as these things go. But we're supposed to laugh because we all "know" that schools could be so much better if only they received more money. The message is that spending more on schools is so obvious that only someone who cares nothing for children could be against it.

I wish it was just the Onion that keeps the conventional-wisdom flame burning. But so does America's newspaper of record. The New York Times editors recently gave their interpretation of international test score rankings, and it's a tour de force of conventional-wisdomizing about schools. Does the U.S. need elaborate teacher training, centralized school funding, and more egalitarianism? Conventional wisdom says "yes," and the Times' editors whole-heartedly agree. I criticized the editorial in a piece for National Review:
Glancing at the list of the best-performing countries, the editors tell some just-so stories to explain the PISA rankings. They start with Finland, which is said to have strict teacher-training requirements. Is that a lesson for education policy that, in the Times’ words, “can no longer be ignored by the United States”? While it’s true that education training in the U.S. generally lacks the rigor of other college-level programs, there is little evidence that increasing formal entry requirements – e.g., creating a “teacher bar exam” – will ultimately improve teacher effectiveness....

Who else sees class-size reduction here?
The Times editors have engaged in what education scholar Jay Greene calls the PISA Rorschach test. The rankings are like an inkblot, and what people see in the inkblot is not a new insight, but rather a reflection of their preexisting preferences. To glean any real lessons for education policy from the PISA data, the Times’ editors will need to look somewhere other than deep within themselves.
Read the whole thing here.