Table 9 . --Regression equations ^ coefficients of determination (R^), and 

 standard errors for the key variables , based on 

 mechanical, counter relationships 



Variable \ 





Regression • 

 equation ; 



Coefficient of ; 

 determination • 

 (R2) = 



Standard 



^V^ "V^ /*v "V* 



error 





VEHICLE TRAFFIC -COUNTER REGRESSION 





Season- long number of 

 visits 



Yl 



= -3.63 + 1.29 (TC) 



0.67 



17.68 



use (hours) 



Y6 



= -1,596.40 + 148.79 



(TC) .37 



3,855.29 



Season- long number of 

 groups 



Y7 



= 0.47 + 0.29 (TC) 



.66 



4.16 



n = 22 













TR.AIL 



PRESSURE-PAD COUNTER 



REGRESSION 





Season- long number of 

 visits 



Yl 



= 9.33 + 0.84 (PC) 



.83 



14.85 



Season- long recreation 

 use (hours) 



Y6 



= 2.12 + 104.21 (PC) 



.48 



4,145.85 



Season- long number of 

 groups 



Y7 



= 5.20 + 0.16 (PC) 



.69 



4.00 



n - 14 



The prototype ultrasonic beam counters could not be kept in adjustment and operat- 

 ing long enough to yield any usable counts. The counters operated well when tested 

 indoors, but failed in the field, probably due to temperature fluctuations and moisture. 

 The trail pressure-pad counter and traffic counters worked quite satisfactorily, how- 

 ever, and yielded useful information. 



The regression equations expressed interview information obtained from entering 

 visitors for the three key variables as linear functions of the corresponding pressure- 

 pad counter (P.C.) and traffic counter (T.C.) covariate values (table 9). The analysis 

 revealed that trail pressure-pad counters and vehicular traffic counters hold promise 

 in estimating number of perso7is and number of groups, but that mechanical counters 

 were essentially useless in estimating total visitor-hours. The single trail pressure- 

 pad counter provided more precise estimates of number of persons and groups than did 

 vehicular traffic counters on two access roads. However, both types of counters were 

 inferior to registration boxes in estimating use. 



30 



