Leo, I thought this comment thread was dead, but I'll chime back in. You are welcome to have the last word. I'm hopeful we'll continue to dialogue and debate in other settings. I’ll cross-post my reply on my blog so more folks can extend the discussion.
1. I It is ad hominem (and silly) to characterize me among "those on the ultra-right." You are attempting to impeach my credibility by using a shortcut label. That isn't a response to my argument, but to me as a person—that's exactly what the conventional (not liberal) interpretation of "against the man" means. Whether you did it thoughtfully or reflexively, your introductory salvo remains ad hominem. Your writing and public testimony is full of loaded language like "privatize" “dismantling” etc. When those you support have a plan, you call it a “proposal”, when you oppose a plan you call it a “scheme”. Your use of language is nuanced and persuasive, but don’t pretend it doesn’t reveal a heavy bias. In the circles where you live, work, and publish, labeling someone “ultra-right” demonizes them.
2. Thanks for the primer on inferential statistics. Ravitch does cross the line from correlation to causation, and she does so explicitly. Why else would she reference both Finland’s rate of unionization and their high performance on PISA? In fact, Ravitch explicitly offers her analysis in response to the argument “teachers’ unions were no help to education reform.” That phrase “no help” is a causative argument, not a correlation. It may be subtle, and it may be poorly warranted, but Ravitch is attempting to refute a causative argument (of her own straw-man phrasing) with a correlational argument. Are you suggesting that Ravitch thinks unions are neutral? She is both making a rebuttal argument and claiming that no argument can be made.
3. Here you make a legitimate argument about which changes are driving improved performance in MA. I don’t know that answer, but like many dynamics in education, there are probably multiple causes. That will take much more rigorous research than currently exists. (It is disingenuous to pretend that I have advocated some increase in the number of standardized tests, or that the reforms in MA are just about testing—please substantiate or drop that line of [reasoning]) What is obvious though, is that improvement in MA has occurred in an environment of reform, and that the reforms in MA happened over the robust objections of the unions. I am convinced that if the type of charter school you advocate elsewhere had been proposed in MA 15 years ago, the union would have opposed it, calling it a “scheme” of the “ultra-right” to “cherry-pick” students, “drain resources” “privatize” public education etc.
Ultimately, the existence of charter schools will make public education better. The presence of healthy and balanced assessment systems will make public education better. The healthy checks and balances of teacher unions will make charter schools better. Teacher resistance and potential for decertification will make unions better. What won’t improve the situation is muddled argumentation and attacks on messenger with whom you disagree.
This is in response to Leo's re-comment
1. You have a rather liberal notion of ad hominem argument.
2. You also don’t seem to understand the distinction between correlation and causation. Yes, Ravitch says there is a correlation between high academic performance and strong teacher unions in Massachusetts. Both exist at the same time and in the same place, which is what qualifies as correlation.
What she doesn’t say is that there is a causal relationship, that strong teacher unions cause high academic performance. That is a different claim, with an entirely different status. There are many correlations that clearly do not qualify as causal.
Lots of things are correlated with high academic achievement. Take geography, for one example. On the whole, northern states have a higher academic performance than southern states. But no one would seriously argue that the geography is causal. Rather, there are historical reasons why northern states are better performers.
3. Massachusetts was always a high performing state. What changed in the last decade was that it went to the very top of the pack. You leave out of your account a number of very plausible reasons why that might have happened. For example, Massachusetts had a successful adequacy lawsuit, supported by teacher unions and opposed by the sort of privatizing reformers you so admire, which dramatically increased the revenues and resources going to public schools, and especially those schools serving the neediest students. As an explanation for moving from the top 5% of states to the very top, that is a whole lot more plausible than your claim for increasing the numbers of standardized tests.