Graduation rates are likely to go up for the third year in a row, and gaps are closing between poor and minority kids and their peers.

So does that mean that the Obama administration’s K-12 policies when it comes to school turnarounds and accountability are on the right track, as U.S. Secretary of Education Arne Duncan has claimed?

Short answer: Maybe. Maybe not. No way to know for sure.

Much longer and super wonky answer: Duncan is leaving office in a couple months—just as Congress is deciding whether to keep some of his key policy initiatives enshrined in a reauthorization of the Elementary and Secondary Education Act.

In two recent interviews, he’s used a rise in graduation rates—and shrinking gaps in those rates between groups of students —to make the case for two of his most prominent policies:

a) The School Improvement Grant program, which gave states billions to turn around the schools that fall in the bottom 5 percent performance-wise. The administration really wants to see a requirement for state to tackle the bottom bunch of schools in a revised ESEA.

b) Waivers from many of the mandates of the No Child Left Behind Act that folks in the civil rights community (and some prominent lawmakers) say really hurt poor and minority kids.

Let’s take them one at a time.

First, the School Improvement Grants.

Duncan said last week that the program, which doled out more than $5 billion over the last several years, was particularly focused on high schools with high drop-out rates. And now that grad rates are on their way up, the investment seems to be paying off.

“Part of the dividend [of SIG] is these high school graduation rates at all-time highs,” he told reporters during a roundtable last week.

But the student achievement data for SIG—which deals with the specific schools, not a national data set—has been a decidedly mixed bag. About two thirds of schools are indeed getting better, but another third actually slid backwards. (Those outcomes are for the first two years of the program, after Duncan and company expanded and overhauled it. And the administration hasn’t released any new SIG data in a long, long time.)

Does an improvement in national graduation rates paint a brighter picture of the SIG program (which only impacts a couple thousand schools, not the whole country)? Not necessarily, experts say.

“It’s difficult to link changes in rates to a given policy,” said Sterling Lloyd, who works in the Editorial Projects in Education research center. “I would be skeptical about making that link.”

And Morgan Polikoff, an assistant professor at the University of Southern California’s Rossier School of Education, said it’s tough to use state level graduation rate data to make claims about a program that affects just a handful of schools.

“I wouldn’t infer that SIG has worked from examining state-level results (and I’d want to see more outcomes than just graduation rates, anyway),” he wrote in an email. “It’d be great to see graduation results broken out by SIG schools to see if that claim holds up.”

Second, the waivers.

The NCLB waivers asked states to concentrate turnaround efforts on their lowest-performing schools and a handful of schools with big achievement gaps. That let schools with other problems essentially off the hook, some have argued.

What’s more, the department has allowed states to use statistical techniques like “super subgroups,” which combine different groups of students (like say, English Language Learners and poor kids) for accountability purposes. Advocates and some lawmakers worry that could mask gaps. (More on how the department has arguably scaled back accountability through waivers here.)

Duncan has been a leading voice in trying to beef up accountability in ESEA reauthorization. But when I asked him recently (for admittedly the second or third time) if he was the one who originally let the accountability toothpaste out of the tube through waivers, he had this to say:

“You’ve asked that question repeatedly and I give the same answer,” he said. “If you look across the nation and see high school graduation rates at all-time highs and drop out rates at all-time lows, and every subgroup of students, every subgroup of students black, white, Latino, Native American, English Language Learners, students in special education, every subgroup improving in terms of graduation rates, which I think is the most important measure, I don’t think we’ve been soft.”

So do higher graduation rates—and graduation rate gaps closing—really mean waivers didn’t hurt subgroup kids?

No way to know just yet, said Polikoff, who has studied the waivers. After all, waivers have only been in place for about three years.

“I think it’s way too early to evaluate the impact of the waivers (indeed, [the Institute of Education Sciences] has just recently funded a few impact studies, and those will really provide the first good evidence),” he said. “It won’t be long until we’re able to test this empirically.”

What’s more, Laura Hamilton, the associate director of RAND Education, a research organization in Santa Monica, Calif., said it’s tough to claim that increases or changes in grad rates are the result of relatively recent policy moves, since graduation rates are a “lagging indicators of changes made earlier students’ K-12 experience.”

In fact, if she had to guess, she thinks the higher rates could be a byproduct of NCLB Classic:

“I suspect some of the gain in grad rates is a result of state accountability policies adopted under NCLB that emphasized the need to improve grad rates, and it’s possible the original subgroup requirements helped by incentivizing schools to devote more resources to groups that had been traditionally underserved,” Hamilton wrote in an email. But she cautioned that, “this is speculation; it’s hard to know exactly what factors contributed to the change.”

Duncan is hardly the first policymaker to take credit for student outcomes. Republican and Democratic presidential candidates make the same sort of claims, and get the same kinds of cautions from researchers.

What’s more, Duncan may live to regret crediting his policies for gains in graduation rates. Scores on the National Assessment for Educational Progress (or NAEP), the nation’s report card, are slated to be released next week—and the rumor is that they are not very good. (I haven’t seen them or talked to anyone who has.)

Plenty of smart researchers would allege “misNAEPery” if folks point the finger at Duncan to explain why scores have dropped (if they drop).

But in using gains in grad rates gains to defend his policies, Duncan may have opened the door to that type of criticism, Polikoff said in an email.

“If you were to accept [Duncan’s] arguments [on waivers and SIG] as being fair/reasonable, and if (as I hear may be the case) NAEP scores are about to take a dip, wouldn’t you logically have to conclude that these very same policies had negative effects on test scores? That’s the fundamental weakness of misNAEPery (or in this case, deGRADation)... once you accept that level of evidence in favor of your preferred position, there’s no way to reject similar-quality evidence that runs counter to your preferred position,” he said.

Or as someone else put it on Twitter:

Arne claimed credit yesterday for rising grad rates. Can’t have your cake and eat it too. https://t.co/pvmcucD42v

— Trace Urdan (@Trace_Urdan) October 22, 2015

Photo: Arne Duncan, left, speaks during a town hall meeting as President Barack Obama looks at North high school in Des Moines, Iowa. Photograph: Charlie Neibergall/AP