Marcado de los recipientes a presión recargables "UN"

The immediate impact of having low teacher quality is poor educational outcomes. Moreover, low teacher quality diminishes the returns of investment in human capital accumulation in the long run. Thus, the direct policy implication of my study is very straightforward. To improve the teacher quality, getting out of a separating equilibrium and move towards a pooling equilibrium must be the goal of the US educational reform. The problem is that moving from a separating equilibrium to a pooling equilibrium is not an easy task because government has to come up with extra revenue to pay higher wages to teachers. It may also take a long time to arrive at the new equilibrium. I make several suggestions that can improve the average quality of teachers and speed up the transition.

a) Pin down the determinants that make good teachers.

Many researchers have been trying to figure out which teacher characteristics are critical to improve students’ academic performance. They have looked at many ex-

ante observable teacher credentials including teaching certification status, advanced education degree, college major, and competitiveness of colleges. However, little evidence has been found that these qualifications, except teaching experience, can significantly increase students’ academic achievement. Teaching experience is not a

useful hiring standard if most applicants are new to teaching. Nailing down some other teacher qualifications can help set better hiring standards for teachers.

b) Raise the standard for the minimum qualification for public school teachers. Increasing the average value of will raise the average teacher quality. As the

value of gets larger, the threshold for the pooling equilibrium becomes smaller. Then, it is easier to satisfy the condition to reach a pooling equilibrium. One way to increase the average value of is to raise the lower bar to become a teacher. For instance, screening the applicants by the minimum college GPA and by the course grade of their teaching subjects or increasing the passing scores for teaching certificate tests can increase . Raising the standards adds more competition among applicants,

which can support higher teacher salaries.

c) Raise teacher salary significantly.

Teacher salaries should be at least comparable with what teachers can earn in the non-teaching sector. Unless the notion of “underpaid teachers” disappears, high quality people will refrain from entering the teaching sector. The small increase in teacher salaries can only incur additional education spending without improving average education quality. Manski (1987) also suggested that the average ability of the teaching force could be improved and the size of the teaching force could be maintained if the minimum ability standards were to be combined with sufficient salary increase. We may consider keeping the current wage schedule for existing

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teachers and use the new wage schedule for new teachers who passed stricter screening processes.

d) Fire the worst teachers.

Giving tenure to all teachers does not seem to be a good strategy when the average quality of the teachers is already low. A documentary film, “Waiting for Superman”, reveals the common practice called “The dance of the lemons”. The principals trade their worst teachers, lemons, hoping that the new lemon they receive is better than the one they just got rid of. Firing the worst teachers, therefore, can eradicate this custom. In fact, firing the worst teacher seems a necessary task for any educational reform to work in the U.S. because it changes the composition of current stock of teachers. Assuming that spotting a few worst performing teachers is not a difficult task, we can expect an immediate positive impact on the average teacher quality of current teaching force by letting the worst-performing teachers go.

Many people have a very hopeful view towards the current education reform, which introduces the teacher evaluation and bonus system to public schools. The advocates of the pay for performance system believe that a low quality teacher could become a good quality teacher by providing simple financial incentives (Woessmann. 2011). According to a recent experimental study by National Center on Performance Incentives (NCPI) at Vanderbilt University (Springer et al. 2010), however, the bonus system of teacher pay did not show a significant effect on students’ academic performance. Other researchers also found similar

There is no accurate measurement for teachers’ productivity. Besides, teacher evaluation is a complex task as it is subjective, labor-intensive, and possibly fraud-inducing. Recently, 178 schoolteachers and superintendents were accused of cheating on standardized tests in Atlanta. This was not the only incident related to cheating teachers for the last several years. D.C., California, Florida, and Massachusetts were among the other states reporting similar events. Even when schools invite the third party evaluators, the evaluation content itself may not be unbiased. Another concern is that having an evaluation on a regular basis is very costly. A recent estimate shows that the teacher evaluation system will cost Washington D.C. 7 million dollars a year. The incentive pay system, therefore, might not be a cost- effective method to improve educational outcome. Instead of putting lots of resources on implementing teacher evaluation, raising teacher salaries significantly enough to attract higher quality teachers and to retain them in the teaching sector might be a better strategy.