“Which came first, the chicken or the egg?” is an age-old question, but is more importantly a dilemma about identifying the real cases of cause and consequence.

Recall from a recent post that currently in the state of California nine public school students are challenging California’s teacher tenure system, arguing that their right to a good education is being violated by job protections that protect ineffective teachers, but do not protect the students from being instructed by said teachers. Recall, as well, that a wealthy technology magnate [David Welch] is financing the whole case, as also affiliated and backed by Students Matter. The ongoing suit is called “Vergara v. California.”

Welch and Students Matter have thus far brought to testify an all-star cast, most recently including Thomas Kane, an economics professor from Harvard University. Kane also directed the $45 million worth of Measures of Effective Teaching (MET) studies for the Bill & Melinda Gates Foundation, not surprisingly as a VAM advocate, advancing a series of highly false claims about the wonderful potentials of VAMs. Potentials that, once again, did not pass any sort of peer review, but that still made it to the US Congress. To read about the many methodological and other problems with the MET studies click here.

If I was to make a list of VAMboozlers, Kane would be near the top of the list, especially as he is increasingly using his Harvard affiliation to advance his own (profitable) credibility in this area. To read an insightful post about just this, read VAMboozled! reader Laura Chapman’s comment at the bottom of a recent post here, in which she wrote, “Harvard is only one of a dozen high profile institutions that has become the source of propaganda about K-12 education and teacher performance as measured by scores on standardized tests.”

Anyhow, and as per a recent article in the Los Angeles Times, Kane testified that “Black and Latino students are more likely to get ineffective teachers in Los Angeles schools than white and Asian students,” and that “the worst teachers–in the bottom 5%–taught 3.2% of white students and 5.4% of Latino students. If ineffective teachers were evenly distributed, you’d expect that 5% of each group of students would have these low-rated instructors.” He concluded that “The teaching-quality imbalance especially hurts the neediest students because ‘rather than assign them more effective teachers to help close the gap with white students they’re assigned less effective teachers, which results in the gap being slightly wider in the following year.”

Kane’s research was, of course, used to support the claim that bad teachers are causing the disparities that he cited, regardless of the fact the inverse could be also, equally, or even more true–that the value-added measures used to measure teacher effectiveness in these schools are biased by the very nature of the students in these schools that are contributing their low test scores to such estimates. As increasingly being demonstrated in the literature, these models are biased by the types of students in the classrooms and schools that contribute to the measures themselves.

So which one came first? The chicken or the egg? The question here, really, and that I wish defendants would have posed, was whether the students in these schools caused such teachers to appear less effective when in fact they might have been as equally effective as “similar” teachers teaching more advantaged kids across town. What we do know from the research literature is that, indeed, there are higher turnover rates in such schools, and oftentimes such schools become “dumping grounds” for teachers who cannot be terminated due to such tenure laws – this is certainly a problem. But to claim that teachers in such schools are causing poor achievement is certainly cause for concern, not to mention a professional and research-based ethics concern as well.

Kane’s “other notable finding was that the worst teachers in Los Angeles are doing more harm to students than the worst ones in other school systems that he compared. The other districts were New York City, Charlotte-Mecklenberg, Dallas, Denver, Memphis and Hillsborough County in Florida.” Don’t ask me how he figured that one out, across states that use different tests, different systems, and have in their schools entirely different and unique populations. Amazing what some economists can accomplish with advanced mathematical models…and just a few (heroic) assumptions.