The Minneapolis and St. Paul school districts rank poorly for their achievement gaps, but better than average on improving student test proficiency, judged against a select group of big-city peers nationally, according to a foundation that describes itself as libertarian.

The research by the Reason Foundation, released Wednesday, is limited to 15 large districts nationally that have moved toward school-based budgeting, in which more dollars closely follow students to the schools they attend. Minneapolis got an A from the foundation and St. Paul a B for principal control over budgets, hiring and training, and for school-level empowerment on such measures as transparency of results and budgeting policies.

Overall, the study ranked Minneapolis sixth and St. Paul ninth among the studied districts on academic and autonomy measures. But they were last and third from the last, respectively, for their achievement gaps. Minneapolis ranked last for its 2011 graduation rate, while St. Paul was second best. The study didn't include 2012 graduation rates, in which Minneapolis recorded a 5 percentage point gain, to 50.1 percent.

"It's data that we know," said Michelle Walker, chief executive of the St. Paul district. She said St. Paul favors allocating dollars in a way that follows students, factoring in their extra needs such as special education, learning English or dealing with a poverty background. But she said the foundation may credit the district with more school autonomy than it has in reality. Minneapolis is in early internal discussions of how it can revamp its budget to promote more equitable achievement among students, according to finance chief Robert Doty.

The academic measures for the first-time study are largely based on standardized test scores and on a protocol used by the education-focused Broad Foundation to select high-achieving urban districts. That is likely to raise red flags among some teacher activists who argue that it's a reductionist approach that inaccurately summarizes the complexity of measuring what a student is learning. One indication of the researchers' ideology is that they gave more credit for school autonomy if teachers' unions had made contract concessions on work rules.

The two key academic measures were standardized state tests for math, reading and science, and graduation rates. For example, actual district test proficiency was measured, both overall and for grade-level and demographic groups. Proficiency was also compared to other districts in a state, ordered by their degree of poverty, to see if districts did better or worse than predicted. Growth in proficiency over four years was measured, and compared to other districts in a state.

Much the same was done for achievement gaps. Using a district's relative rank within its state, a comparison was also made to the relative ranking of the other 14 districts in other states.

The comparisons were selective. For example, Asian-Americans make up the largest bloc of St. Paul students, but achievement gap calculations didn't compare them as a group against whites, and their proficiency as a group wasn't used in some measures.

For Minneapolis, the methodology found that the district's low-income students had among the state's lowest proficiency rates for such students, while students from better-off families had relatively high proficiency against statewide peers. Black math proficiency rose in high school rose faster than that of black students in most state districts. Reading and science proficiency rose for Latino and black and low-income students but was not much different from the norm for such students statewide.

St. Paul had better proficiency for white, Latino, low-income and higher-income groups than such groups had statewide, but its black students had lower proficiency and were improving more slowly than elsewhere in Minnesota. The research found St. Paul has some of the state's largest achievement gaps between low-income and other students of all state districts and isn't closing them.

Minneapolis ranked last in achievement gaps between low- and high-income students. See Minneapolis' rankings below and the full detailed report on the district at http://tinyurl.com/kpdnuu7.

St. Paul ranked second in graduation rates. See St. Paul's rankings below and the full detailed report on the district at http://tinyurl.com/kdc9bg3.

You can find the full study at http://tinyurl.com/km77kau.

Steve Brandt • 612-673-4438

Twitter: @brandtstrib