The Mechanism of Cycles 



95 



A Comparison of the Coefficients of Correlation in 

 Case of Linear Yield-Price Curves and of Linear 

 Demand Curves 



The data used in the above computation were, in 

 case of the yield-price curve, the average yield per acre 

 of the respective crops in the whole of the United 

 States and the corresponding average prices for the 

 United States, on the first of December of the years in 

 which the crops were produced. The data for the 

 demand curves, it will be recalled from the preceding 

 chapter, were the total supply of the respective crops 

 in the United States and the corresponding prices on 

 December 1. The period covered in both cases was 

 from 1866 to 1911, inclusively. The data were ob- 

 tained from recent Yearbooks of the United States 

 Department of Agriculture. 



It appears, from the coefficients of correlation given 

 in the above Table, that it is possible to predict the 

 prices of the crops from the yield per acre with the same 



