56 



Maine Agricultural Experiment Station. 1920. 



in the use of them for the determination of the corrections to 

 be applied to the correlations from double-selected data as was 

 done by Rietz. 



The Correlation; of Jersey 8 Months Milk Production 

 With the Age at Test. 



Common knowledge among dairymen is that milk produc- 

 tion and age at the commencement of the lactation are corre- 

 lated in such a way that advancing age means increased produc- 

 tion. The opinion is general that this increase is a linear one. 



TABLE 3. 



Correlation Surface for Pounds of Milk and Age at Test for 



Jersey Cattle. 

 (Lactation Period 8 Months). 



= = = = 



a o o 



— — ?: 









a 





o 



o 















































a 









L^ 



a 



■■c 



i> 



*-. 







c-- 



a 



- = 





- 







- 



- 



o 







- 

























































»- 







-j-. 



c. 



08 



=. 



1:6-2:0 





5 



15 



10 



2 2 















34 



2:0- 2:6 



1 



4 



19 



54 



51 



56 42 



19 



7 



2 



















255 



2:6- 3:0 







1 



4 



6 



7 



11 12 



4 



4 





















49 



3:0- 3:6 









4 



21 



22 



33 30 



20 



13 



P 



3 



2 















156 



3:6- 4:0 







3 



3 



6 



9 



14 19 



16 



8 



7 



3 



5 



2 



1 











96 



4:0- 4:6 









2 



8 



15 



31 24 



25 



15 



7 



8 



1 



2 





1 









139 



4:6- 5:0 











7 



11 



13 20 



24 



13 



8 



3 



5 



3 



1 







108 



5:0- 5:6 











7 



• 13 



16 14 



23 



10 



5 



7 



9 



2 



1 1 





108 



5:6- 6:0 











5 



13 



12 19 



17 



15 



14 



9 



4 



3 



3 



" 1 



115 



6:0- 6:6 









2 



2 



10 



14 8 



14 



12 



12 



5 



6 



3 



3 



1 





92 



6:6- 7:0 











4 



6 



9 15 



IS 



12 



16 



8 



7 



4 



1 



2 



1 



100 



7:0- 7:6 







2 



1 



4 



5 



16 11 



19 



7 



6 



5 



5 



2 









83 



7:6- 8:0 











3 



11 



8 9 



9 



14 



14 



9 



5 



1 



3 1 





87 



8:0- 8:6 









1 



7 



7 



7 10 



15 



8 



7 



4 



2 



1 



1 1 71 



8:6- 9:0 











2 



8 



8 3 



12 



7 



6 



5 



3 



1 



1 56 



9:0- 9:6 







1 



3 



4 



3 



7 



9 



7 





3 



5 



1 





43 



9:6-10:0 







1 



3 



1 



3 



4 



6 



8 



5 



5 



3 



1 



1 



1 







42 



1 : -1 :>, 











1 



1 



3 



9 



6 



1 



1 



4 















26 



10:6-11:0 







1 





3 



3 



2 



2 



4 



3 



3 



1 



1 



1 











24 



11:0-11:6 









1 



3 



2 



6 5 



3 



4 



1 





1 













26 



11:6-12:0 















2 



1 



1 





1 

















5 



12:0-12:6 









1 



3 







2 



1 



o 



















9 



12:6-13:0 













1 



o 



1 



2 



1 



















7 



13:0-13:6 









1 





1 



1 





1 



1 



















5 



13:6-14:0 















1 









1 

















2 



14:0-14:6 

















1 



1 





















2 



14:6-15:0 









































15:0-15:6 













1 





















1 



15:6-16:0 



























Total 1 13 



50 



166 



212 



279 274 



266 



162 



127 



82 



58 



26 



15 3 2 2 3 1741 



