Center of 





Center of 





Height Increment 



Number 



Height Increment 



Number 



ft, NGVD 



Selected 

 5 



ft, NGVD 



Selected 



7.9 



9.4 





8.0 



4 



9.5 





8.1 



4 



9.6 





8.2 



3 



9.7 





8.3 



3 



9.8 





8.4 



3 



9.9 





8.5 



2 



10.0 





8.6 



2 



10.1 





8.7 



2 



10.2 





8.8 



2 



10.3 





8.9 





10.4 





9.0 





10.6 





9.1 





10.8 





9.2 





11.0 





9.3 





11.2 





NOTE: These are the numbers of events selected for each set of 50 events. 



Total events selected at each height increment would be three times 

 the numbers found in this table. 



area were chosen from this ranked set. This method of transferring these 

 surge plus tide time-histories to the study area was determined during cali- 

 bration of the storm surge model (see Part III). 



22. Figure 5 shows the fourth and final part of the selection process, 

 the assignment of probability to the selected events. The probability p , 

 represented by each stage increment, is calculated by taking the difference of 

 the exceedance probabilities P of the end points of the increment. If more 

 than one event was selected to represent that stage increment, then the prob- 

 ability assigned to that increment is divided equally among the chosen 

 events. Table 3 contains the maximum water levels (predicted at the Boston 

 gage) and the probabilities assigned to the three sets of selected events. 

 The column in Table 3 labeled "Storm" refers to the numbering of the storms in 

 Table 1 . Note that since the selection process is random, not all the storms 

 are represented in each of the three sets of 50 events (denoted as A, B, and C 

 in Table 3), and the number of times a storm is chosen varies from set to set. 

 In conclusion, the essence of the selection process is to choose events for 

 simulation so that the stage-frequency curve, for a known location is 



