RURAL AND AGRICULTURAL EDUCATION 11 



figure "13" after his name in this same column. Next decide 

 which man should be considered as second most successful and 

 place a figure "2" after his name. Likewise decide who should 

 be considered next to the least successful and place a figure 

 "12" after his name. Continue this, working from the extremes, 

 until the numbers "1" to "13" appear in the "Finance" column 

 representing the numbering of the men were it possible to stand 

 them up before one in the order of their financial success. 



Follow this same procedure for "Physical Capacity" as 

 defined. Again imagine the thirteen men to be standing in line 



before you. The order would be some- 



The Spearman "foot what different. W. B. (See form A) e. g. 

 rule" formula pro- would be transferred to a position two 

 vides a simple meth- places up from the lower end of the scale, 

 od for obtaining de- The next two men would hold their old 

 sired correlations places. T. H. would go up one place. W. 

 from the data at W. would go down one place. N. S. 

 hand. leaves fifth for first place. H. F., a very 



successful man financially, goes to the 



lowest place so far as physical capacity is concerned. In spite 

 of this one considerable change, together with several lesser 

 ones which keep the balance, you will feel that as a whole there 

 has not been any very decided re-arrangement. The two sep- 

 arate rankings of the men are not very dis-similar. This like- 

 ness, or unlikeness, as the case may be, can be measured can 

 be weighted and stated as a single number. The "Delta Column" 

 gives the basis for this measurement. The positive differences 

 must always equal the negative differences. The total of either 

 may be known as Summation G(SG). Applying the Spearman 

 Foot Rule Correlation formula 7 the value of this mutual relation- 



6SG 



7. R=l . SG in this case equals "14" and n (num- 



n 2 1 



6x14 



bcr of men) equals "13." R=l -=.500. It is custo- 



1691 



mary to state the Spearman values in terms of the Pearson 

 formula values and in this case R(fp)=.500 or r(fp)=.732. See 

 pages 167 to 177 Thorndike's Mental and Social Measurements. 



