WILLIAMBURG, Va. – Two economics professors at the College of William & Mary are shedding some light on President Obama’s so-called “free” community college tuition proposal.

Professors Robert B. Archibald and David H. Feldman, experts in college costs, crunched the numbers and made a chart that shows Obama’s “America’s College Promise” idea to give away two years of community college to “responsible students” is far from free for taxpayers, the Washington Post reports.

The chart “shows an estimate of the initial fiscal cost of making community college ‘free’ in each state, measured as dollars per thousand of that state’s personal income,” the researchers wrote, according to the news site.

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“We say ‘initial’ and ‘estimated’ because we have no way to know precisely how many current students would qualify for aid (those in the appropriate programs with the requisite GPA) and how many more students will move into the system.

“Even without that extra knowledge, it’s clear that there is a lot of variation nationally. In Florida, for instance, the cost is 33 cents per thousand. In Kentucky, it’s three dollars and a penny.”

The chart shows the estimated cost to each state for the “free” tuition program, ranging from around 10 cents per thousand dollars of personal income in Alaska to nearly $3.50 per thousand in Iowa.

What’s abundantly clear is the program would not be “free” for taxpayers, as states would be required to cover a quarter of the cost, while the federal government would pick up the other three-quarters.

There are also some other things to think about, the researchers said.

“One of the program’s goals is to break down the financial barriers that keep many students from pursuing a useful certificate or degree. Two free years at a community college supposedly will make a four-year bachelor’s degree more affordable. Yet four-year colleges and universities depend on larger classes taught to first and second year students to keep cost down,” they wrote in the Post.

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“These larger introductory classes are the flip side of the smaller and more teacher-intensive upper level classes of the final two years. The upper division courses are the ones that truly prepare students for a job market that prizes advanced training in technical and non-technical fields alike.

“If the proportion of freshmen and sophomores at four-year universities falls (due to students taking advantage of the ‘free’ community college program), this could push up the cost of a four-year degree for students who go directly to places like Ohio State or Oregon. Welcome to the ‘law of unintended consequences.’”

That could be a problem because research shows that students who go directly to a four-year institution are more likely to graduate than those who begin in community college.

Politics will also play into the issue, the researchers noted, and it remains unclear whether states would be willing to foot their part of the bill.

“Since the federal government is picking up ¾ of the tab, states like Iowa, South Carolina and Arizona (the latter two quite red), would be clear net recipients of federal money even though they would have to kick in some extra cash themselves (the other ¼),” they wrote in the Post.

“How would South Carolina’s leadership react? Not sure.”

Here’s the professors’ chart, courtesy of the Post: