human capital

Wide margins of error, instability on city's value-added reports

Some English Language Arts teachers received high "value-added" scores in 2007 but much lower scores in 2008.

The value-added reports meant to measure city teachers’ effectiveness have wide margins of error and give judgments that fluctuate — sometimes wildly — from one year to the next, a new analysis finds.

Schools Chancellor Joel Klein has instructed principals to use the Teacher Data Reports as one way to decide which teachers should receive tenure. Teachers who teach English or math to students in grades three through eight receive the reports.

The NYU economist Sean Corcoran found that 31 percent of English teachers who ranked in the bottom quintile of teachers in 2007 had jumped to one of the top two quintile by 2008. About 23 percent of math teachers made the same jump.

There was an overall correlation between how a teacher scored from one year to the next, and for some teachers, the measurement was more stable. Of the math teachers who ranked in the top quintile in 2007, 40 percent retained that crown in 2008.

The Annenberg Institute for School Reform at Brown University, which has a history of criticizing the Bloomberg administration, published Corcoran’s findings, which were part of a wider look at the practice of assigning “value-added” scores to teachers based on their students’ test scores.

The analysis explains the difference between what value-added scores of teachers aim to do and what value-added measurements actually do in practice. The dream is to isolate the effect of a teacher on students’ performance from the effect of everything else; the reality is that the measures approximate that isolated effect with statistics, weak tests, and small sample sizes.

Corcoran offers some praise. “The simple fact that teachers and principals are receiving regular and timely feedback on their students’ achievement is an accomplishment in and of itself, and it is hard to argue that stimulating conversation around improving student achievement is not a positive thing,” he writes. “But,” he writes,

teachers, policymakers, and school leaders should not be seduced by the elegant simplicity of “value-added.”

The weaknesses of value-added detailed in the report include:

  • the fact that value-added scores are inherently relative, grading teachers on a curve — and thereby rendering the goal of having only high value-added teachers “a technical impossibility,” as Corcoran writes
  • the interference of imperfect state tests, which, when swapped with other assessments, can make a teacher who had looked stellar suddenly look subpar
  • and the challenge of truly eliminating the influence of everything else that happens in a school and a classroom from that “unique contribution” by the teacher

Another challenge for the teachers and principals charged with using value-added scores for self-improvement is the uncertainty about what each individual teacher’s score actually is. On each teacher’s report, the city pinpoints the percentile ranking that represents how she compares to other teachers of the same subject and grade.

But while this is the ranking that the teacher most likely holds, it’s far from 100 percent certain. Indeed, the economists who make value-added scores can only be very certain that the teacher falls somewhere on a range of percentiles (and even getting that cautious, they’re still only 95 percent certain). This range, as you might remember from statistics, is called the “confidence interval.”

For most teachers, the confidence interval is at least 30 percentage points long. For math and English teachers with only one year’s worth of data, the average length is over 60 percentage points. That’s a range of, for instance, between the 10th and 70th percentile of teachers.

The average confidence intervals that Corcoran reports are in the chart below. You can see that, because the confidence intervals shrink as the sample size grows, they are longest when only a year’s worth of data is available.

Teachers in the Bronx face the least certainty. Corcoran guesses that this is because their students are the most likely not to be measured, thereby lowering the data pool — either because the students are classified as special ed or English language learners, and don’t take the state test, or because the students move from year to year, making data about their growth over time harder to come by.

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The full report is here and below.
The Use of Value-Added Measures of Teacher Effectiveness in Policy and Practice

first steps

Superintendent León secures leadership team, navigates evolving relationship with board

PHOTO: Patrick Wall
Superintendent Roger León at Tuesday's school board meeting.

As Newark’s new superintendent prepares for the coming academic year, the school board approved the final members of his leadership team Tuesday and began piecing together a roadmap to guide his work.

The board confirmed three assistant superintendents chosen by Superintendent Roger León: Jose Fuentes, the principal of First Avenue School in the North Ward; Sandra Rodriguez, a Hoboken principal who previously oversaw Newark Public Schools’ early childhood office; and Mario Santos, principal of East Side High School in the East Ward. They join three other assistant superintendents León selected for his team, along with a deputy superintendent, chief of staff, and several other officials.

The three assistant superintendents confirmed Tuesday had first come before the board in June, but at that time none of them secured enough votes to be approved. During last month’s meeting, the board assented to several of León’s leadership picks and to his decision to remove many people from the district’s central office, but it also blocked him from ousting several people.

This week, Board Chair Josephine Garcia declined to comment on the board’s reversal, and León did not respond to a request for comment.

What is clear is that the board and León are still navigating their relationship.

In February, the board regained local control of the district 22 years after the state seized control of the district due to poor performance and mismanagement. The return to local control put the board back in charge of setting district policy and hiring the superintendent, who previously answered only to the state. Still, the superintendent, not the board, is responsible for overseeing the district’s day-to-day operations.

During a board discussion Tuesday, Garcia hinted at that delicate balance of power.

“Now that we’re board members, we want to make sure that, of course, yes, we’re going to have input and implementation,” but that they don’t overstep their authority, she said.

Under state rules, the board is expected to develop district goals and policies, which the superintendent is responsible for acting on. But León — a former principal who spent the past decade serving as an assistant superintendent — has his own vision for the district, which he hopes to convince the board to support, he said in a recent interview on NJTV.

“It’s my responsibility as the new superintendent of schools to compel them to assist the district moving in the direction that I see as appropriate,” he said.

Another matter still being ironed out by the board and superintendent is communication.

León did not notify the full board before moving to force out 31 district officials and administrators, which upset some members. And he told charter school leaders in a closed-door meeting that he plans to keep intact the single enrollment system for district and charter schools — a controversial policy the board is still reviewing.

The district has yet to make a formal announcement about the staff shake-up, including the appointment of León’s new leadership team. And when the board voted on the new assistant superintendents Tuesday, it used only the appointed officials’ initials — not their full names. However, board member Leah Owens stated the officials’ full names when casting her vote.

The full names, titles and salaries of public employees are a matter of public record under state law.

Earlier, board member Yambeli Gomez had proposed improved communication as a goal for the board.

“Not only communication within the board and with the superintendent,” she said, “but also communication with the public in a way that’s more organized.”

The board spent much of Tuesday’s meeting brainstorming priorities for the district.

Members offered a grab bag of ideas, which were written on poster paper. Under the heading “student achievement,” they listed literacy, absenteeism, civics courses, vocational programs, and teacher quality, among other topics. Under other “focus areas,” members suggested classroom materials, parent involvement, and the arts.

Before the school year begins in September, León is tasked with shaping the ideas on that poster paper into specific goals and an action plan.

After the meeting, education activist Wilhelmina Holder said she hopes the board will focus its attention on a few key priorities.

“There was too much of a laundry list,” she said.

early dismissals

Top Newark school officials ousted in leadership shake-up as new superintendent prepares to take over

PHOTO: Patrick Wall
Incoming Newark Public Schools Superintendent Roger León

Several top Newark school officials were given the option Friday to resign or face termination, in what appeared to be an early move by incoming Superintendent Roger León to overhaul the district’s leadership.

The shake-up includes top officials such as the chief academic officer and the head of the district’s controversial enrollment system, as well as lower-level administrators — 31 people in total, according to documents and district employees briefed on the overhaul. Most of the officials were hired or promoted by the previous two state-appointed superintendents, Cami Anderson and Christopher Cerf, a sign that León wants to steer the district in a new direction now that it has returned to local control.

The officials were given the option to resign by Tuesday and accept buyouts or face the prospect of being fired by the school board at its meeting that evening. The buyouts offer a financial incentive to those who resign voluntarily on top of any severance included in their contracts. In exchange for accepting the buyouts, the officials must sign confidentiality agreements and waive their right to sue the district.

Earlier this week, León submitted a list of his choices to replace the ousted cabinet-level officials, which the board must approve at its Tuesday meeting. It’s not clear whether he has people lined up to fill the less-senior positions.

It’s customary for incoming superintendents to appoint new cabinet members and reorganize the district’s leadership structure, which usually entails replacing some personnel. However, many staffers were caught off guard by Friday’s dismissals since León has given little indication of how he plans to restructure the central office — and he does not officially take the reins of the district until July 1.

A district spokeswoman and the school board chair did not immediately respond to emails on Friday about the shake-up.

Some staffers speculated Friday that the buyout offers were a way for León to replace the district’s leadership without securing the school board’s approval because, unlike with terminations, the board does not need to sign off on resignations. However, it’s possible the board may have to okay any buyout payments. And it could also be the case that the buyouts were primarily intended to help shield the district from legal challenges to the dismissals.

León was not present when the staffers learned Friday afternoon that they were being let go, the employees said. Instead, the interim superintendent, Robert Gregory, and other top officials broke the news, which left some stunned personnel crying and packing their belongings into boxes. They received official separation letters by email later that day.

The people being ousted include Chief Academic Officer Brad Haggerty and Gabrielle Ramos-Solomon, who oversees enrollment. Also included are top officials in the curriculum, early childhood, and finance divisions, among others, according to a list obtained by Chalkbeat.

In addition to the 31 being pushed out, several assistant superintendents are being demoted but will remain in the district, according to the district employees.

There was concern among some officials Friday about whether the turnover would disrupt planning for the coming school year.

“I don’t know how we’re going to open smoothly with cuts this deep,” one of the employees said. “Little to no communication was provided to the teams about what these cuts mean for the many employees who remain in their roles and need leadership guidance and direction Monday morning.”