64 



THE BELL SYSTEM TECHNICAL JOURNAL, JANUARY 1952 



COMPUTED DATA COMPARABLE TO j FACTOR ANALYSIS DATA 

 COMPUTED DATA COMPARABLE TO SENDER MONITORING CIRCUIT DATA 



m 60 



< 40 



2 4 6 8 10 12 14 16 18 20 



TIME, t, IN SECONDS TO FIRST ACTION TAKEN BY A SUBSCRIBER 



FROM RECEIVER OFF HOOK 



Fig. 19 — Subscriber dialing habits based on individual line records when dial 

 tone is delayed indefinitely. 



Table IV with the vakies developed earlier in connection with the 

 j factor analysis. 



These results are not considered to be inconsistent since the tails of 

 the survivor curves were constructed from very meager data. Conclu- 

 sions based on Figs. 17(a) to 19(b) should therefore be regarded as 

 having qualitative value only. The results principally indicate that the 

 waiting-for-dial-tone characteristics of subscribers clearly vary with the 

 different classes of service. 



Comparisons between the lower survivor curves on Figs. 17(a) to 

 19(b) and the curves on Figs. 13 to 15 of the sender monitor tests are 

 indicated by the percentages given in Table V of subscribers waiting for 

 dial tone 5, 10 and 15 seconds from the time they requested service. 



