Falling teacher aptitude.

In their article "Wage Distortion: Why America's Top Female College Graduates Aren't Teaching" (Research, Spring 2005), Caroline Hoxby and Andrew Leigh make a compelling argument related to the impact of wage compression on the market for public school teachers. Their findings suggest that the imposition of price ceilings, through collective bargaining, has restricted the supply of high-achieving females entering the teaching profession, resulting in a shortage in the marketplace. To once again attract top female graduates into teaching, Hoxby and Leigh propose creating pay for performance systems for teachers similar to those used in other occupations.

Economists have long held that restrictions on the free movement of price in a market will result in disequilibrium between supply and demand. So, the cause and effect that Hoxby and Leigh demonstrate is not an unexpected outcome in the education labor market. It is striking, however, that wage compression seems to have a stronger effect than the standard explanation--increase in job opportunities for women.

From my experience, however, there is another factor, not discussed in the article, which may have a comparable impact on the supply of high-quality teachers: The ease or ability to enter the teaching profession.

Historically, at the same time that collective bargaining exerted downward pressure on salaries, excessive regulations and requirements for teacher certification inserted barriers and restricted entry to the teaching profession. The teaching profession has long confused increase in regulations with promoting higher standards. Unfortunately, limiting access had the opposite effect on teacher quality. As other jobs were opening doors for high-achieving female graduates, the teaching profession closed them.

It was in response to the issue of entry to the market that alternative certification programs have been developed. For example, the American Board's Passport to Teaching certification program allows talented, motivated college graduates to demonstrate mastery of subject matter and knowledge of teaching through a series of rigorous examinations. Opening access has been a big step forward to recruiting high-achieving females; creating performance-based compensation programs would be a giant leap.

KATHLEEN MADIGAN 

President, American Board for Certification of Teacher Excellence