32. The most significant statistical relationship, following prelimi- 

 nary analyses, appeared to be the reduction of significant wave height between 



buoy 1 and buoy 2, as revealed by the scattergrams. SPSS procedures, which 



p 

 computed multiple stepwise regression of HS2 with factors including HS1, HS1 , 



HSI-^, TP1 , and TP1 were executed. Table 16 is a summary of a run where cases 



with TP1 < 4 sec were excluded. The independent variables are listed in 



order of their relative significance in the regression equation: 



A + B,X, + BoXo + 



'ri 



2^2 



•+ B„X„ 

 n n 



(24) 



where A and B are constants and X is the independent variable. The 

 changes in the correlation (R ) indicate that HS1 provides the only important 



correlation, with TP1 as next most important though comparatively insignifi- 



2 

 cant. Nonlinear correlations were not revealed by inclusion of the HS1 , 



HS1- 



or TPT^ terms. 







Table 



16 









Regression 



Summary i 



["or the Mult 



ipie Linear 



Regression 



of HS2 





with HS1, HSl^, 



HSl3, TPl, 



and TPl^ foi 



- TPl > 4 



sec 



















Variable 



Multiple 

 R 



! R 

 Square 



0.55725 



RSQ 

 Change 



0.55725 



Simple 

 R 



E 



Beta 



HS1 - Sig Wave Ht 1 



0.74649 



0.74649 



0.44623 



1.11870 



TP1 - Peak Period 1 



0.76011 



0.56266 



0.00542 



-0.02561 



-0.02978 



-0.30323 



TP1SQ - TPeakl Squared 



0.75218 



0.56578 



0.00312 



-0.05501 



0.00108 



0.24627 



HS1SQ - HSIG1 Squared 



0.75358 



0.56788 



0.00209 



0.67612 



-0.07965 



-0.66127 



HS1CU - HSIGl Cubed 



0.75513 



0.57022 



0.00235 



0.56785 



0.01090 



0.33109 



(Constant) 











0.26593 





33. Scattergrams of HS2 with HS1 which excluded cases with TPl values 

 below an increasing lower limit showed increasing correlation. Figure 16 is 

 a scattergram of HS2 with HS1 where cases with TPA < 12 sec were excluded. 

 The R computed was 0.73 with 405 cases included. The grouping near axes 

 intersection and along the HS2 = HS1 line is typical of all the scatter- 

 grams where only lower TPl values were excluded. Figure 17 is a scattergram 

 of HS2 with HS1 where the following conditions were specified: TPl > 12 sec 

 HS2 > 0.5 m , and HS1 > 1.5 m . The R^ computed was 0.75 with 38 cases 



38 



