Even though I know the world is round, little is on the level and Tony Soprano can’t live much longer, I never stopped to think that colleges would be serving as bagmen for lenders, skimming profits to fill their penurious pockets in the process.

I guess I wanted to believe that colleges were honest informants when it came to the art of financing school, there to help freshmen from getting collegially fleeced.

But they were not. Colleges were steering students to aggressive loaners delighted to give college officials financial kickbacks for helping to increase their share in the annual $85 billion student loan business.

And while New York’s attorney general Andrew Cuomo has made the whole country aware that financial officers at colleges are to be doubted, there are more dire money questions hounding every college student.

For starters: Does college pay off financially? What does your money really buy you? Will you pay too much? How to compare offers? And why is there such a premium on higher education these days?

Naturally, I don’t have any answers, but Malcolm Getz, associate professor of economics at Vanderbilt University, has written a penetrating book entitled, Investing in College, A Guide for the Perplexed, Harvard University Press. And while it’s not a breezy read, it provides keener insight into some of the more complex questions than do the college guides.

Before we delve into the manual, I have to tell you that it was my good friend, Tim Napier, the college counselor extraordinaire at the Hopkins School, who stumbled upon it at R. J. Julia’s the other week, read it, and pronounced it a must read.

The book makes the assumption that many families pay too much for college and attempts to help the reader to discern the differences in quality worth paying for, which cannot be spotted if a student only focuses on college rank.

Viewed as investment, the question then is not whether you’re paying a shade extra on student loans, but rather will a family’s long-term wealth be greater with this investment in education than it would be if the funds were invested in a typical portfolio of financial assets.

The short answer, according to Getz, is that on average, higher education will give the family a higher rate of return. Getz points out that more years of education and higher degrees are positively correlated with increased earnings up to a point, and in certain fields more than others.

It’s helpful for students to see that different occupations show different patterns of income over a lifetime. Nursing and engineering pay off faster in the short term but provide less long-term growth. Medicine, however, shows a smaller jump in earnings at the beginning, but provides more sustained growth.

“So the question of how much higher education to buy is strongly influenced,” Getz says, “by the choice of career.” As well as a hundred other things that he goes into.

The book addresses trends in earnings and education, whether undergraduate degrees pay off, and the same for postgraduate degrees. I found it interesting to learn that a PhD has been a very good buy for women but not such a good buy for men.

And while it’s fairly well established that salaries increase as the level of education increases, Getz notes that “the top one-sixth of males with high school diplomas earn as much as the bottom one-sixth of males with PhDs.”

In addition to raw talent and intelligence, this wide dispersion reflects differences in the quality of education, the commitment to work, and the risks taken in pursuing careers, and he notes; we can’t forget the role of mistakes and just dumb luck.

If you can tolerate a surfeit of statistics in a guidebook, I think you’ll find the book a good investment. It has the obligatory section on finding true bargains in education and it offers insight on how to balance net price with quality.

Now even if you don’t get around to the book, it would be interesting to ask your college student if he thinks the cost of college is a superior investment.