高等教育的成績膨脹

Grade inflation of higher education

張彧昕(Chang-Yu Hsin)

指導教授 ： 江莉莉

共同指導教授 ： 楊秉訓(BIING-SHIUNN YANG)

淡江大學/商管學院/經濟學系經濟與財務碩士班/碩士(2022年)

https://doi.org/10.6846/TKU.2022.00064

摘要

伴隨著高等教育的擴張，大學生的在校成績出現膨脹現象。在勞動市場上，在學成績往往是新進受雇者的技能與生產力的訊號；雇主提取該訊號，以決定各個技能的受雇者之薪資。因此，成績膨脹現象，尤其是成績壓縮，將影響雇主對訊號的反應，從而改變高等教育體系的教學與學習誘因，衝擊勞動市場的生產力與相關者的福利。本研究設立一個結合勞動市場薪資決定的學生與教師的賽局模型，探討成績膨脹的衝擊與成因。
首先設立完全訊息的基準模型，模型中勞資雙方從受雇者可觀察的產出，依協商取得分配份額，而學生與教師即依照勞動市場的薪資表，同步決定各自的努力程度。其次，考量勞動市場的訊息不對稱，探討廠商如何根據在學成績所提供的訊號，決定受雇者的薪資，以及學生與教師在預期個別技能的薪資下，如何作成最適決策，並分析成績膨脹對均衡的影響以及福利效果。接著，延伸單一訊號的訊息不對稱模型為二元訊號模型，加入校外的證照考試成績做為第二訊號，重新檢視成績膨脹對師生雙方的決策與福利的影響。最後則是將單一訊號模型中的教師調分措施內生化，以找出成績膨脹的成因。
在完全訊息的均衡下，影響教師與學生決策的因素包括勞動市場上雇主的議價能力、學生的努力成本參數，以及勞動技能的邊際生產力。當勞動市場存在訊息不對稱時，本文發現成績壓縮使得高能力的學生與教師的期望效用皆提高，至於低能力學生的期望效用之變動方向則無法判定。接著當勞動市場存在二元訊號時，學校成績壓縮使得低能力學生與教師的期望效用皆降低，而高能力學生的期望效用之變動方向無法判定。最後舉一特例將教師調分決策內生化，例中教師僅針對能力低於平均水準的學生，在其依照本身學習成效取得的成績上加一固定分數。本文發現在此調分特例中，教師調分幅度主要決定於雇主的議價能力、勞動技能的邊際生產力，學生的努力成本參數與教師調分的邊際損失參數等因素。此外，調分會造成雇主對成績訊號反應增強，從而強化教師所考量的各項因素對調分幅度的影響。

關鍵字

成績膨脹 ； 成績壓縮 ； 成績訊號 ； 師生賽局

並列摘要

With the expansion of higher education, college students' grade in school has expanded. In the labor market, academic grade is often a signal of the skill and productivity of new hires; employers extract this signal to determine the salary of employees of various skills. As a result, grade inflation, especially grade compression, will affect employer responses to signals, thereby changing the incentives for teaching and learning in the higher education system, impacting labor market productivity and the welfare of those involved. This study establishes a game model of students and teachers combined with wage determination in the labor market to explore the impact and causes of grade inflation.
First, a benchmark model of complete information is established. In the model, labor and firms allocate shares from the observable output of employees according to a bargaining rule in the labor market, while students and teachers simultaneously determine their respective effort levels according to the wage structure of the labor market. Secondly, considering the information asymmetry in the labor market, it explores how firms determine the wage schedule of employees based on the signals provided by school grades, and how students and teachers make optimal decisions based on the expected wages of individual skills, and analyzes the effects of grade inflation on game equilibrium and welfare of both teachers and students. Then, the information asymmetry model of the single signal is extended to the dual- signal model, and the results of the license examination outside the school are added as the second avenue of labor market signaling to re-examine the impact of grade inflation on the decision-making and welfare. The last extension of the model is to endogenize the teacher's grading measures in the single-signal model to find out the causes of grade inflation.
In the equilibrium of complete information, the factors that affect the decision-making of teachers and students include the bargaining power of employers in the labor market, the effort cost parameter of students, and the marginal productivity of labor skills. When there is information asymmetry in the labor market, this paper finds that grade compression increases the expected utility of both high-ability students and teachers, while the direction of change in the expected utility of low-ability students cannot be determined. Then, when there are dual signals in the labor market, school grades compression reduces the expected utility of both low-ability students and teachers, while the direction of change in the expected utility of high-ability students cannot be determined. Finally, a special case is given to internalize the teacher's decision to adjust the grades. In this case, the teacher only targets students whose ability is lower than the average level, and adds a fixed score to the grades obtained according to their own learning results. This paper finds that in this special case of adjustment, the extent of teacher adjustment is mainly determined by the employer's bargaining power, the marginal productivity of labor skills, the parameter of student effort cost and the parameter of marginal loss of teacher adjustment. In addition, grading increases the response of employers to performance signals, thereby enhancing the influence of various factors considered by teachers on the scale of grading.

並列關鍵字

grade inflation ； grade compression ； signaling of grade ； game between teachers and students

參考文獻

參考文獻

邱于真編譯 (2019), 〈淺談分數膨脹 (grade inflation)：當 "A 等第" 變成平均時〉，原文：Jed Applerouth (2019), “Grade Inflation: When A is for Average.” Retrieved from https://www.applerouth.com/blog/2019/11/12/grade-inflation-when-a-is-for-average/

Bar, Talia, Vrinda Kadiyali, and Asaf Zussman (2009), “Grade Information and Grade Inflation: The Cornell Experiment,” Journal of Economic Perspectives, 23 (3): 93-108.

Chan, William, Li Hao and Wing Suen (2007), “A Signaling Theory of Grading Inflation,” International Economic Review, 48(3), 1065-90.

De Paolo, Maria and Vincenzo Scoppa (2010), “A Signalling Model of School Grades under Different Evaluation Systems,” Journal of Economics, 101, 199-212.