APS trial witness: Improved test scores’ odds? One in 288 septillion


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Students in one fourth-grade class at Dobbs Elementary School had a one in 288 septillion chance of doing as well as they purportedly did on a 2009 standardized test, a witness said Thursday in the Atlanta Public Schools cheating trial.

“That’s 27 zeros,” University of Michigan professor Brian Jacob said, trying to help jurors understand the enormous number.

Jacob testified the mind-boggling figure represented the odds that one class would score so much higher on the spring 2009 Criterion-Referenced Competency Test than had been predicted when the teacher gave students a “benchmark” test at the beginning of the school year.

Jacob, a professor of statistical analysis and education policy, is the prosecution’s expert witness as the Fulton County District Attorney’s Office wraps up its case against 12 former educators charged with engaging in a racketeering conspiracy to inflate test scores. Prosecutors contend the goal of the alleged conspiracy was to ensure the Atlanta schools district showed mandated improvements that would reflect well on its educators and then-Superintendent Beverly Hall.

Hall’s reputation for turning around failing schools earned her nationwide acclaim and financial bonuses. The charges of cheating and racketeering brought down her administration and ruined multiple teaching careers.

Thursday was the 56th day of testimony in the trial, which began on Sept. 29 following a jury-selection process that started in August and lasted six grueling weeks. Prosecutors have told Fulton County Superior Court Judge Jerry Baxter they expect to call their final witnesses Tuesday. Then defense attorneys for the educators will present their cases. The trial is expected to conclude in late March or early April.

On the witness stand Thursday, Jacob compared numbers for the entire state in 2009 and statistics for school districts in Georgia that are similar to Atlanta’s. In the comparisons, he included Atlanta schools that had been flagged for cheating because of a high number of erasures on the CRCT, as well as those that had not been flagged.

Another fourth-grade class at Dobbs also saw dramatic improvements on the CRCT over what was expected. The odds of that happening? One in 4 quintillion, Jacob said.

“That is highly, highly unlikely,” said the professor, who returns to the witness stand on Monday and is also expected to testify Tuesday.