macro

bball strength;
  repeat num;
  store r.1-r.m1.
 
# using bradley-terry model, simulates season 
# where each team plays each other 8 games (4 home and 4 away)

##################################################################
#  MACRO 'BBALL'                                                 #
# -------------------------------------------------------------- #
#  SIMULATES A SEASON OF BASEBALL                                #
##################################################################

mcolumn strength team h_team a_team p ones h_stgth a_stgth temp equal
mcolumn game1 game2 game3 game4 win_1 win_2 win_3 win_4 lose_1 lose_2 lose_3
mcolumn lose_4 winner loser c99 c100 c101
mcolumn r.1-r.m1 
mconstant k1 k2 k3 k4 k5 k6 k7 k8 k9 k10 k11 i num j SEASON
#mconstant s.1-s.n
default num=1

# copy s.1-s.n strength
let k1=count(strength)
set team
1:k1
end
set ones
1( 1 : 1 / 1 )k1
end

let h_team=team
let h_stgth=strength
let a_team=1*ones
let a_stgth=strength(1)*ones
do k3=2:k1
 stack h_team team h_team
 stack h_stgth strength h_stgth
 let temp=k3*ones
 stack a_team temp a_team
 let temp=strength(k3)*ones
 stack a_stgth temp a_stgth
enddo

let equal=h_team=a_team
copy h_team a_team h_stgth a_stgth h_team a_team h_stgth a_stgth ;
 omit equal 1.

let k4=k1*(k1-1)

let p=1/(1+exp(a_stgth-h_stgth))

do j=1:num

rand k4 game1 game2 game3 game4;
 uniform 0.0 1.0.
note
let game1=game1<p
let game2=game2<p
let game3=game3<p
let game4=game4<p

let win_1=h_team*game1+a_team*(1-game1)
let win_2=h_team*game2+a_team*(1-game2)
let win_3=h_team*game3+a_team*(1-game3)
let win_4=h_team*game4+a_team*(1-game4)
let lose_1=a_team*game1+h_team*(1-game1)
let lose_2=a_team*game2+h_team*(1-game2)
let lose_3=a_team*game3+h_team*(1-game3)
let lose_4=a_team*game4+h_team*(1-game4)

stack win_1 win_2 win_3 win_4 winner
stack lose_1 lose_2 lose_3 lose_4 loser
if repeat=0
  table winner loser
endif

let k6=30
let k7=30+k1-1
let k8=50
let k9=50+k1-1
let k10=70
let k11=70+k1-1
let SEASON=j
if repeat=1
  print SEASON
endif
tally winner;
store c99 c100.

# rank c100 c101
# let c101=k1+1-c101

if store=1
  do i=1:k1
    let r.i(j)=c100(i)
  enddo
endif

# if st_pos=1
#  do i=1:k1
#    let t.i(j)=c101(i)
#  enddo
# endif

enddo

endmacro