NSWC/WOL TR 76-155 



However, should the reader require for example the probability, 

 P (level 2 injury), it is just the difference, P (level 2 or greater) - 

 P (level 3 or greater). 



3.2 OBSERVED INJURIES TO SPOT VS CALCULATED OSCILLATION PARAMETER 

 Figure 3.2.1 shows the experimentally observed injuries (as 

 shown in each row of Table 3.1.3) to Spot on the 1973 and 1975 tests 

 plotted as a function of Z = 100 In AMAX/AMIN. There are three plots, 

 one for each of the injury levels 1, 2, and 3. The plotted points 

 represent the percent of fish of a given size at a given specimen 

 location receiving injuries of the indicated level or greater. 



To investigate the functional dependence of the observed 

 injury on the calculated oscillation parameter Z we constructed 

 Table 3.2.1 and Figure 3.2.2. Table 3.2.1 was constructed from 

 Table 3.1.3 by reordering (sorting) the entries in order of increas- 

 ing value of Z and then separating the new table into groups repre- 

 senting approximately 100 fish. The total observed injuries for each 

 group was then summarized by the successive row entries in Table 3.2.1. 

 Thus, for the first group with a mid-range value for Z=54; 41% of the 

 fish received injuries of level 1 or greater; 11%, level 2 or greater; 

 and 5%, level 3 or greater. 



Figure 3.2.2 shows plots of the averaged injury data tabulated 

 in Table 3.2.1. The solid curves are drawn by eye through the data 

 points. The experimental data for level 3 injuries to Spot exhibit 

 less scatter than that for levels 1 or 2 ; and also less than for all 

 levels of injury to White Perch (Section 3.3), Whether or not this 

 has any physical significance is not known. 



Also shown, as a dashed line in Figure 3.2.2, is the equation 



(3.2.1) 



1 + EXP [-0.055(Z-125) ] 



where p is the probability of observing injury of level 3 or greater, 

 Equation 3.2.1 is the Cumulative Logistic Probability Function with 



38 



