Figure A-4. Road Network Surrounding Concord, New Hampshire. 



50 Miles 



cord were measured. A regression equation of the form D 

 was derived: 



+ b P 



D 



Where: 

 D 



P : 



= - 1.534 + 1.351P 



= road distance in miles 



= radial distance in miles 



(correlation coefficient: 0.982) 



Figure A-5 shows the theoretical limits to the road mile - radial 

 mile relationship. If every farm is located on a radial road, the 45-degree 

 line will apply with the regression equation having an a value of zero 

 and a b value of 1.0. This also means that a very large number of radial 

 roads exists, assuming an even distribution of farms over the country- 

 side. The 4 radii line in Figure A-5 is the second limit, resulting from 

 the theoretical model discussed above. This line has an a value of zero 



42 



