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._|\|   |/|_.  Copyright (c) 1981-1990 by the University of Waterloo.
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 <____ ____>   Waterloo Maple Software.
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#
#  PROTO, Sensitivity Analysis Example
#
#  Equations of the model:
#
>     eq1 :=           y = w*h + s  :
>     eq2 :=   p*(1+t)*c = a*y      :
>     eq3 :=         w*j = (1-a)*y  :
>     eq4 :=         w*l = a*y - s  :
>     eq6 :=           l = q/b      :
>     eq7 :=           p = w/(b-1)  :
>     eq8 :=       t*p*c = s        :
#
#  Some parameters and exogenous variables:
#
>     b := 2.040:
>     h := 100.0:
>     p := 1.000:
#
#  For several values of parameter "a" solve 
#  the base run (tax=0.2), change the tax and then
#  solve the policy run (tax=0.3):
#
#  CASE 1: a = 0.285
#
>     a := 0.285:
>     t := 0.200:
>     fsolve({eq1,eq2,eq3,eq4,eq6,eq7,eq8},{y,w,s,c,l,j,q});
     {s = 5.186351706, c = 25.93175853, q = 50.86614173, j = 75.06561680,

         l = 24.93438320, y = 109.1863517, w = 1.040000000}

>     t := 0.300:
>     fsolve({eq1,eq2,eq3,eq4,eq6,eq7,eq8},{y,w,s,c,l,j,q});
     {w = 1.040000000, s = 7.321531494, c = 24.40510498, q = 47.87155208,

         j = 76.53355290, l = 23.46644710, y = 111.3215315}

#
#  CASE 2: a = 0.255
#
>     a := 0.255:
>     t := 0.200:
>     fsolve({eq1,eq2,eq3,eq4,eq6,eq7,eq8},{y,w,s,c,l,j,q});
     {j = 77.80678851, w = 1.040000000, s = 4.616187990, c = 23.08093995,

         q = 45.27415144, l = 22.19321149, y = 108.6161880}

>     t := 0.300:
>     fsolve({eq1,eq2,eq3,eq4,eq6,eq7,eq8},{y,w,s,c,l,j,q});
     {w = 1.040000000, s = 6.502656314, c = 21.67552104, j = 79.15815284,

         q = 42.51736821, l = 20.84184716, y = 110.5026563}

#
#  CASE 3: a = 0.315
#
>     a := 0.315:
>     t := 0.200:
>     fsolve({eq1,eq2,eq3,eq4,eq6,eq7,eq8},{y,w,s,c,l,j,q});
     {j = 72.29551452, q = 56.51715040, w = 1.040000000, s = 5.762532982,

         c = 28.81266491, l = 27.70448549, y = 109.7625330}

>     t := 0.300:
>     fsolve({eq1,eq2,eq3,eq4,eq6,eq7,eq8},{y,w,s,c,l,j,q});
bytes used=1001360, alloc=786288, time=.766
     {q = 53.30568229, l = 26.13023642, y = 112.1526338, s = 8.152633762,

         c = 27.17544587, j = 73.86976359, w = 1.040000000}

#
#  Done
#		 
>     quit;
bytes used=1150780, alloc=786288, time=.900