GUIDES FOR USE OF RISK 



RISK is a computer program written by Walker and Duncan (1967) that calculates the 

 nonlinear regression coefficients of the logistic function utilizing the algorithm just 

 discussed. The program has been modified to handle data with unequal sampling weights 

 attached to each observation. The program is written in FORTRAN IV and has been run 

 on an IBM 360/67. Requests for the program should be directed to: 



Intermountain Forest and Range Experiment Station 

 Forestry Sciences Laboratory 

 Attention: David A. Hamilton, Jr. 

 1221 S. Main 

 Moscow, Idaho 83843 



Control Cards 



Field Function 

 Card 1 



Value 



Column Nam.e Format 



Problem identification 



1-80 IDF.NT 20A4 



Card 2 



Regressor set number 

 Run number 



XX ... X 



XX ... X 



1-10 

 11-20 



ANRS 

 AN 



F10.0 

 F10.0 



Number of parameters to be 

 estimated (< 30) 



xx . 



21-30 



ANR 



F10.0 



Number of observations in 

 population 



Is input file on cards? 



xx ... x 



Yes = 



31-40 

 41-50 



AN0 

 ATAPF 



F10.0 

 F10.0 



No = input unit 

 number containing 

 input file 



12 



