1  REM uncertainty: if difference * 20 < sum,
2  REM then stay with the natural inclination;
3  REM otherwise, use Arthur routine

10 INPUT N                                       ' number of adopters
20 SCREEN 11: WINDOW (-2, 0)-(N, 100): CLS       ' set up screen
22 LINE (-2, 50)-(N, 50)
23 RANDOMIZE TIMER

25 FOR J = 1 TO 15                               ' number of runs
40    AR = .8: BR = .2                           ' initialise parameters
42    SA = .2: BS = .8
43    NA = 1: NB = 1
44    S = .01: R = .01
50    FOR I = 1 TO N
70        CHOICE = RND
80        IF (NA - NB) > 0 THEN M = (NA - NB) ELSE M = (NB - NA)
90        IF CHOICE < .5 GOTO 125
100       IF M * 20 > (NA + NB) GOTO 109
101       NA = NA + 1
102       GOTO 140
109       RETURNA = AR + R * NA: RETURNB = BR + R * NB
120       GOTO 130
125       IF M * 20 > (NA + NB) GOTO 129
126       NB = NB + 1
127       GOTO 140
129       RETURNA = SA + S * NA: RETURNB = BS + S * NB
130       IF RETURNA > RETURNB THEN NA = NA + 1 ELSE NB = NB + 1
140       X = NA + NB: Y = 100 * NA / X
150       PSET (X, Y)                         ' set point on screen
160     NEXT I
165 NEXT J
170 END