SOME DELIBERATELY MISLEADING RESEARCH:

This week a new empirical study claiming to show that public schools do a better job than private schools has made a big media splash. But the study is deeply misleading. The authors make claims their statistical method can't possibly justify. And if you guessed that the study got off the ground with help from the educational status quo, you'd be right. If there's one thing education research has shown, it's that private schools do a better job than public schools. The consensus in favor of this among empirical studies is as strong as on anything in education-policy research. Indeed, this is just the sort of thing that makes people wonder why we social scientists spend so much time doing empirical studies to prove things that everybody already knows.

Well, one reason we do it is to counteract the effects of propaganda and bad research. This new study, conducted by researchers at the University of Illinois, was first published by an openly anti-voucher think tank located at Columbia University's Teachers College. It's getting media play now because it was picked up by the journal of Phi Delta Kappa, a professional organization for teachers. The authors themselves make no bones about what their real target is. One author told the Christian Science Monitor that their study "really undercuts a lot of those choice-based reforms." Translation: People only support vouchers because they don't realize that private schools are actually worse than public schools.

Another reason why the study is getting attention is owing to its size: The data set includes 23,000 students. People tend to assume that a big study is automatically good. But the same rule applies in research as in so many other things: size does matter, but technique matters a lot more. The researchers take raw test scores from isolated years and apply statistical controls for race, socioeconomic status, and disabilities. While the raw scores are higher in private schools, they find that once you apply the statistical controls public-school students actually have higher test scores. They characterize this as evidence that public schools do a better job than private schools. In fact, it shows nothing of the kind.

The main problem is that they use scores from isolated years. That is, they take a snapshot of student achievement rather than tracking achievement over time. While they do take snapshots from different years, they have no way to track students from one snapshot to the next, which is no better in practice than taking just one snapshot. This is important because if you don't track students over time, you can't establish a causal connection between the type of school a student attends (public or private) and test scores. In other words, their data have nothing to say about the relative quality of public and private schools.

A much more likely explanation for the latest study's results is that when students enter private schools, they tend to have test scores a little lower than other students of their race and socioeconomic status. That seems counterintuitive, because people are used to thinking of private-school students as privileged. And so they are - because of their race and socioeconomic status. But that's precisely what this study controls for. In fact, it makes perfect sense that within each racial and socioeconomic group it's the low performers whose parents will be motivated to make the sacrifices necessary to put them in private schools. What counts is whether those students make better or worse gains over time after they enter private school - and that's just what this study can't tell us. I could go on, but instead I'll let the authors explain it for themselves. Buried in the back of the study, they write:

NAEP data [the test score set they use] do not allow for examinations of growth in achievement over time, nor do they include information about student movement between school sectors. Therefore, correlations between school sector and achievement are not demonstrably causal. In other words, one cannot conclude from this analysis that public schools are more effective at promoting student growth than private schools.

Read that last sentence again: One cannot conclude from this analysis that public schools are more effective at promoting student growth than private schools. So what about all the huffing and puffing in the front of the study - "At this time when market-style reforms are changing the public school landscape, this study offers fresh evidence that challenges common assumptions about the general superiority of private schools," etc.? It's just smoke and mirrors.

As it happens, there's a large body of very high-quality research that does allow us to evaluate the causal connection between school type and student achievement, and it overwhelmingly finds that private schools do better. The most convincing evidence comes from seven studies using "random assignment," the same method used in medical trials. In all seven studies, students who won a random lottery to use a school voucher at a private school had significantly greater test-score gains than similar students who lost the lottery and stayed in public schools. Numerous studies using other methods have also produced a very strong consensus in favor of this finding.

As a general rule, whenever a researcher announces that his study finds something that contradicts all the other empirical evidence, and the finding just happens to coincide with the self-interest of powerful political groups, it's a good idea to do a reality check. One can only hope this study doesn't damage the chances that more students will be empowered to attend superior private schools through voucher programs.

Source




OVERPAID AND UNDERWORKED TEACHERS ON LONG ISLAND: "Moderate" $100,000 salaries for the lucky ones

What you expect from a powerful union

East Islip isn't the only community where teacher pay is under scrutiny. Across the Island, school costs, including salaries, are projected to rise an average of 7.2 percent next year -- the eighth year in a row that spending has outpaced both inflation and enrollment growth. With budget votes coming up on May 17, the spotlight has focused on teacher salaries and benefits, which account for more than 50 percent of most districts' budgets.

Long Beach's school board, for example, is weighing a recommendation for a two-year freeze on teacher's pay. The recommendation comes from a board-appointed committee representing civic associations, business groups and others, and is widely viewed as a bargaining chip in ongoing contract negotiations. For next year, Long Beach proposes a $97.6-million budget that would raise spending 6.2 percent and taxes 9.9 percent.

Proponents of a freeze note that teachers have done better financially than many private-sector workers in recent years. A freeze, these supporters say, would provide homeowners with tax relief. "My husband's working two years without a salary increase," said a member of the advisory group, Mindy Warshaw, whose spouse is an electrician. "And with the rising costs of health care, something's got to give."

Teacher representatives insist that pay raises aren't as high as they appear, because they are offset by retirements of those highest on the pay scale who are replaced by lower-paid teachers. Those representatives add that higher school spending is largely in response to employers' demands for better-trained graduates with advanced degrees. "I hear very few of those business people saying teachers don't deserve what they're getting," said Dick Iannuzzi, a former Central Islip teacher who recently was elected president of New York State United Teachers, the state's largest faculty union. Rather, Iannuzzi added, the usual complaint is that higher spending is simply unaffordable. Teacher unions contend the state should deal with that problem by increasing aid payments to schools, thus curbing local property taxes. Islandwide, raises for teachers generally run 3 percent to 4 percent annually -- a figure that union leaders say reflects the cost-of-living.

Frank Volpe, a Long Beach math teacher who heads the union there, cites this regional pattern in arguing against a local freeze. "Long Beach is no different than any other community, and their teachers shouldn't be treated any differently," he said.

But taxpayer groups and school business managers note these raises are boosted by other provisions buried within contracts - everything from "longevity" raises to additional compensation for college credits - that drive up total compensation 5 percent or 6 percent. All this adds up to a median teacher's salary on the Island of about $67,800 and top pay of about $102,200 for those in the upper 5 percent. Figures are for 2003-04, the latest available, and are the highest for any region in the state

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For greatest efficiency, lowest cost and maximum choice, ALL schools should be privately owned and run -- with government-paid vouchers for the poor and minimal regulation.

The NEA and similar unions worldwide believe that children should be thoroughly indoctrinated with Green/Left, feminist/homosexual ideology but the "3 R's" are something that kids should just be allowed to "discover"

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