6^2 



NATURE 



{Oct. 31, 1889 



the probability integral. A small table based on the 

 latter, but of a totally different form, that I have lately 

 more than once published {pp. di., p. 205, and Nature, 

 vol. xxxix. p. 297). is very convenient for this sort of work. 

 The following is a brief extract from it : — 



Grades of Rank from 0° to 100°, together with the Deviations ^ 

 from the Mean Values at those Grades. 



Some of the consequences of marking separately the 

 relative rank and the absolute performance are seen by 

 the next table. Here the relative rank is in each case 

 supposed to count between the grades of 50° and 100°. 

 Then, if it alone is considered, a man who stands at the 

 grade of 99° in a class that ranges within the limits of o'' 

 and 100°, will be seen to get very nearly the full amount 

 of ten marks, whereas if absolute performance is alone 

 considered, he would get no more than seven marks. 

 The full number of ten could be never actually reached, 

 but only closely approached at some such high grade as 

 99-99 . . .°. The figures in this table would have run very 

 differently if the marks for relative rank had begun after 

 90° and not after 50". Still more so, if the lower limit 

 had been 99°, and more still if it had been 99'''9. It 

 seems to me most reasonable, on the whole, that they 

 should usually begin after 50°, as in the table : — 



The general conclusion to which these remarks lead is, 

 that before arranging scales of marks, the first step is to 

 measure a large number of persons who are of the same 

 class as the expected candidates ; this has already been 

 done to a considerable extent at Cambridge, at Marl- 

 borough College, and elsewhere. Thence to make tables, 

 and to deduce diagrams from them like Fig. i in some 

 cases, and like Figs. 2 and 3 in others. These will exactly 

 determine the qualities of the men to be dealt with, in 

 a statistical sense. It is now the part of those who have 

 to fix the scales of marks to determine the grade at which 

 rank shall begin to count, and to arrange the weight to 

 be given respectively to relative rank and to absolute 

 performance in each sort of examination. This and a 

 few other obvious preliminaries having been settled, the 

 construction of consistent scales of marks would follow 

 almost as a matter of course. 



Experiments at Eton College on the Degree of Concordance 

 between different Exatniners in assigning Marks for 

 Physical Qualifications. By A. A. Somerville. 



An experiment was made at Eton in July last, with 

 the object of obtaining information upon the following 

 points: (i) whether it is possible to frame a system of 

 marking for physical excellence, based partly upon Mr. 

 Galton's system, and partly upon medical examination ; 



' The unit by which the deviations are measured is half the difference 

 between the performances of the persons who respectively occupy the grades 

 250 and 75°. 



(2) whether marks assigned by medical examiners would 

 be as safe a test of excellence as those assigned, e.g. by 

 examiners in English essay. The experiment was con- 

 ducted as follows : — A list of points was drawn up with 

 the help of two able medical men. These points were : 

 (i) breathing capacity, as tested by the spirometer; (2) 

 hearing — (3) eyesight, tested by Snellen's type ; (4) 

 strength, tested by the grip dynanometer ; (5) endurance, 

 tested as follows — after the maximum reading of the 

 dynanometer had been obtained and registered for 

 strength it was again (as nearly as possible) obtained, 

 and the number of seconds during which the candidate 

 could hold the needle of the dynanometer between this 

 reading and the reading 10 below it was taken by a stop- 

 watch ; (6) relation of height to weight ; (7) girth and 

 shape of chest ; (8) general muscular development ; (9) 

 health record, particular inquiries being made as to 

 rheumatism, asthma, and scarlatina : (10) general aspect 

 and condition. 



The first five points depend solely upon measurement, 

 and consequently the marks of the two doctors are the 

 same for those points. The next point was marked, 

 partly by impression and partly by reference to a table of 

 averages, but it might be made to depend altogether upon 

 averages. The seventh and eighth points were marked 

 partly by measurement of chest, arms, and legs, and 

 partly by examination. The last two points depend 

 altogether upon medical opinion, and involved a tho- 

 rough medical examination. Ten marks were assigned 

 for each point, and the examination was conducted inde- 

 pendently by the two doctors in separate rooms. Thirty- 

 two boys were examined : (i) twenty Army Class boys, 

 including ten successful candidates at the recent Sand- 

 hurst and Woolwich Further Examinations, two members 

 of the Cricket XI., and two members of the Rowing 

 Eight ; (2) six other members of the XI. ; (3) the re- 

 maining six members of the Eight. The following table 

 gives the final results, average differences per cent, being 

 calculated with reference to a maximum 50, as the 

 marks for the first five points are the same for the two 

 examiners. (N.B. — Letters are substituted for the names 

 of the boys.) 



Nineteen of the twenty Army boys were subsequently 

 examined in English essay, the essays being marked 

 independently by two examiners, with the following 

 results : — 



