A Class-Mean-Based Method for Assigning Grades to Absent Students Peter R. Adams Pennsylvania State University, York Campus, York, PA 17403 Assigning fair grades to students who, for valid reasons, have been ahsent from scheduled written tests or lahoratory work is always a difficult task. Administering separate tests to these students is often inconvenient and invites charges such as ineouitv and unfairness. Increasing the weight assigned to one & more of the tests that were taken may be unfair to the absent student if the general performance in the missed test was particularly good, or may be unfair to all the present students if the general performance in the missed test was particularly bad. These disadvantages can be substantially mitigated if a reasonable individual estimate can be made of how the absent student would have scored in the missed test had he or she been present. The method suggested here can be effected by the teacher with minimalexpenditure of time with the aidonly of an inexpensive pocket calculator' though it could undouhtedly be adapted to more sophisticat&l media such as a personal commter. A; an illustration consider student P (see table ) who was absent from test no. 4 in which the class mean was 8.4 out of 10 points. His total score for the other five tests that he took is 32 out of 50 points, or a personal average of 6.4. If this average is assiRned to test no. 4 (or an equivalent procedure is devised in which his grade is based on tests that heactually . took) his total score becomes 38.4 out of 60 ~ o i n t s~rohahlv lower than he would have scored bad he taken test 4 since his scores were consistently above the class mean. On the other hand student Q, who missed test no. 2 (class mean 3.6 points) and had earned 27 out of 50 points would, by a similar treatment, be assigned 5.4 points for test no. 2 and a total of 32.4 out of 60,probably more than he would have earned since his earned-grades were consistently below the class mean. Other treatments of these situations may have ~imilar distortions imolicit in them. ----If, however, it is noted that student P's scores for the five tests taken were consistently higher within one standard ~
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deviation of the class means for those tests, a reasonable estimate of what his score would have been for test no. 4 can be made from the class mean (8.4)and standard deviation (1.6) of that test. To do this ouantitativelv. the Darameter Z & i t be calculated2 for each bf the five tests taden, where - individual score z = clam mean standard deviation For student P, these Zvalues would be -0.73, -0.14, -0.53, -0.14, and -0.32 for tests 1,2,3,5,and 6,respectively. The average of the five Z values (-0.37) can then reasonably be assiened to test no. 4 from which a score of 9.0is calculated to prc&ce a total of 41.0 (instead of 38.4 by the previous method) out of 60 points. Similarlv, the Z values for student tests 1,3,4,5,and6, Qare 1.09,1.24,1.~0,0.33,and0.iifor respectively, from which an average Z of 0.87would produce an estimated score of 1.1 for test no. 2 and a total of 28.1 (instead of 32.4)out of 60 points. Probably this is a fairer, more accurate, and quicker to calculate method of grade assignment to absent students than many other methods in current use. I t requires no bookkeeping other than data in the table and entering the class means and standard deviations in the calculator are&am. Once entered in the calculator, the program can be stored indefinitelv and incomorated in the total made-assigning process. lican be used for as many different categories of test and lahoratory work scores as needed and also used in different courses hiving different final grade calculation formulas. Obviously, many modifications could be devised to suit individual needs. Copies of a program that would process data such as the tahle are offered to interested readers upon request directly to the author.
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' me one used here is a Casio fx-4000P ScientificCalculator.
Hopkins. C. D.: Antes, R. L. Classrmm MeasurementandEvaiua tion, 2nd ed.: Peacock: 1985: p 369.
Student Ted Scores (Maxlmum 10 Points per Test) Test Number
1
student P ~ m e s StudemQ Scores Class Means StandardDeviatlons
6 4 5.2 1.1
2 4
3
5
6
6 8.4 1.6
7 6 6.7 2.1
7 6 6.4 1.9
8 5
3.6 2.9
4
7.1 1.7
Volume 66 Number 9 September 1989
717
