Postscript After Grading the 2010 General History of Science Exam

This time I was in charge of grading all three essay questions, and since I also had to watch the World Cup, the grading went a bit slowly. But the two teaching assistants who graded the short-answer section together had already taken a week to get it to me, and they hadn’t arranged the order of the exam papers for me at all, nor had they prepared the electronic roster properly, so my speed was probably still pretty good.

This time, because I had to assign grades for the graduating class first, I rushed through the papers of the class of ’06, and in the process fixed the grading scale. Although I had foreseen that the graduating students would on the whole be somewhat slacker, I still underestimated the overall level, which caused the grading scale for the essay questions to be somewhat too generous; in the end, a few students even received three perfect scores. But it seems the final distribution was controlled just right, and only a slight adjustment to the normal distribution rate was needed to make it work, probably because this time the regular homework scores were generally rather low.

I had already talked earlier about the answering approach to the three major questions. But when I wrote up those approaches, I hadn’t looked at the ppt, so I still didn’t know the directions in which the students had answered. Because many students would answer according to the items on the ppt. Indeed, the ppt provided most of the important points; however, when doing essay questions, the point of the ppt is only to remind you—the key is still to write out what you yourself understand. The problem with many students was precisely that they more or less did not understand the logic among the items in the ppt, nor were they familiar with the background knowledge involved in the corresponding items. For example, the second question asked why modern science arose in Europe. The key points for this question were not only on the ppt; answers to a similar question from last year’s exam had also been published online. So many students simply copied a few items, such as “the genes of ancient Greece,” “the many ideas derived from Christianity,” and so on. But just what ideas did Christianity derive that led to the emergence of modern science? … Merely listing some stiff, dead items—even if copied from the “standard answer”—would not earn high marks from me. The ppt and the model answer are nothing more than hints to some clues; the key is to use your own understanding to lay things out clearly and in an orderly way. The more extreme cases were those in which some students pasted fragmented items onto the paper sentence by sentence, and yet there wasn’t a single complete sentence in the whole essay—how can that be called an “essay question”? Apart from the first question, which was graded mainly according to key points, the latter two mainly looked at understanding and argumentation. If you do not understand the items on the ppt yourself, it is better not to mechanically force them into place; better to write according to your own logic.

Although the first question was graded according to key points, one still had to see how well those key points were grasped. Merely copying the correct items could only earn an ordinary score (15 or 16 points); the explanation of the items would show whether the student had really listened in class and read with understanding, or whether they had simply grabbed the ppt and the book at exam time and copied them indiscriminately. Students who copied from the book at the last minute all had very stiff language, with a heavy patchwork feel, whereas students who had some understanding of the relevant knowledge did not need to cobble things together on the fly; instead, they could connect the key points in their own relatively coherent language and present them smoothly, which earned a high score. A few students made fairly serious factual errors in their discussion, and then even if they had hit the key points, they still had to lose points. For example, ancient Greek astronomy “saved the phenomena” is a key point; but if one then says that in order to “save the phenomena,” Pythagoras proposed the central fire theory, then that is simply wrong. Errors of this sort show that class attendance and reading were clearly not done with care, and I would deduct extra points. Another, less serious kind of error was to absolutize the differences. For instance, it is true that Chinese astronomy emphasized observation and practical use, but it is not correct to say that ancient Chinese astronomy had only observation and no prediction or mathematics; likewise, it is not appropriate to say that Greek astronomy was completely unrelated to calendars and human affairs.

As expected, for the third question, most students came out saying straight away that it “should not be done.” Quite a few students hardly considered why such a question would be raised at all, and instead only kept emphasizing the benefits of history of science; such papers earned low scores. Even some of the benefits of history of science that they praised were precisely the key issues in the discussion about whether history of science should be set as a restricted level—for example, that history of science helps establish role models and helps people learn scientific methods, and so on. Yet setting it as level X was exactly a consideration based on the possibility that history of science might break role models and dissolve scientific methodology. Not understanding the gist of the question and single-mindedly singing the praises of history of science inevitably led to a low score. By contrast, students who said it should be classified as a restricted level actually scored somewhat higher, because at least they had understood the main point of the question. Of course, there were still some unexpectedly good answers—students who had a fairly good grasp both of the question itself and of history of science and education—and there were also some perfect scores.

The average score on the final exam’s short-answer section was 35.0, and the three essay questions averaged 16.3, 15.8, and 15.4 respectively. One unfortunate student thought that in the end it was three choose two, and so failed to do one question. Among the other students, the lowest score I gave on any one question was only 2 points; that student completely failed to understand the third question, and instead wrote that “if history of science were set as level X, objectivity would be undermined,” and only wrote two or three sentences. There were also students whose reasons for the second question were things like population growth, social peace, urbanization, and the spread of stirrups—completely beside the point. How can Europe’s population be compared with China’s? The question here is why modern science was born in Europe. In short, scores below 10 were often given to students whose understanding of the question was seriously off, or whose attitude toward answering was extremely inattentive. A score of 15 to 16 was the middle range, while 18 or above was clearly excellent.

Finally, I made some minor adjustments to the grades based on participation in the course website discussion forum. Generally speaking, if a student posted N times in the forum (ignoring students who posted only once), then [(N-2)/2] would be added to the regular grade; if this score had no effect on the final grade, it would be ignored. Then I made further adjustments for students in the 89~90 and 84~85 ranges. In order to achieve the normal distribution of excellent grades, I had to change two 84.6 scores to 84, and I chose two students who had not posted in the forum and deducted one point from their regular grades to complete the adjustment. As for students with 89 points, if they had participated in forum posting, I would try to adjust them up to 90; if they had not posted, I would not adjust them. In the end, there were 18 students above 90 points; among non-double-degree students, 74 were above 85 points, and among double-degree students, 3 were above 85.

June 21, 2010

Latest Comments

• Yiwu

  2010-06-21 22:17:56

  So complicated… Was the exam paper taken home to write by ourselves?
  Why do you have to consider the normal distribution rate of excellent grades when making corrections?

• Guwa

  2010-06-21 23:01:18

  The exam paper was written in class, and the teaching assistants took the papers home to grade them.
  The normal distribution rate of excellent grades is a school rule, meaning that scores of 85 and above should not exceed 40%; in other words, it means not letting certain teachers be too lenient, or using grades to attract students.

• Yiwu

  2010-06-22 12:52:55

  Was it open-book?

• Guwa

  2010-06-22 17:05:25

  Open-book.

Translated from the Chinese original with AI assistance. The original text is authoritative.