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HARRIS, KIRKPATRICK, BLAKESLEE, WARNER AND CARD 



month, where p is the base of prediction and of (b) the months of the year 

 subsequent to the (p + l)th month will be considered in this place. 5 

 The equations required are as follows: 



Month from uhich pre 

 diction is made 



November 



November 



December 



December 



January 



January 



February 



February 



March 



March 



April 



April 



May 



May 



June 



June 



July 



July 



August 



August 



September 



Period for which prediction is made 



December to October 

 January to October 

 January to October 

 February to October 

 February to October 

 March to October 

 March to October 

 April to October 

 April to October 

 May to October 

 May to October 

 June to October 

 June to October 

 July to October 

 July to October 

 August to October 

 August to October 

 September to October 

 September to October 

 October 

 October 



Prediction equation 



The test of accuracy of prediction of these equations when applied to 

 the 415 White Leghorns of 1917-1918 is given in comparison with the 

 results for the prediction from two-months production (to be discussed 

 later) in tables 5 to 7. 



Limiting our attention for the moment to the errors of predicting the 

 production of the months of the year remaining after any given month 

 used as a basis of prediction, we note that in general the average deviations 



6 In the comparison between the egg production of a period of two months and the egg pro 

 duction of a single month as a basis of prediction, it is necessary to base critical comparisons upon 

 the results of predictions of the records of periods subsequent to the two months under consid 

 eration. Concretely, if we are to compare November-plus-December record with November 

 record and with December record as bases for the prediction of the annual production, the two- 

 month period will contribute more to the annual record than either of the two months individually 

 considered. Neither will contribute to the January-to-October production. We must, there 

 fore, in testing prediction equations, base the test upon the results secured in predicting January- 

 to-October egg record. 



For this purpose we must have equations which show the relation between the egg record of 

 the individual months and the egg record of groups of remaining months. For example, we 

 require for November the January-to-October production; for December, the February-to- 

 October production; for January, the March-to-October production and so on. Fr&amp;gt;r conven 

 ience merely the equations are given here in comparison with the other one-month equatior 



