Qopen=FinancialData["IBM","Open",{{2013,2,16},{2014,3,16}}];
Qclose=FinancialData["IBM","Close",{{2013,2,16},{2014,3,16}}];

Ropen=FinancialData["CAT","Open",{{2013,2,16},{2014,3,16}}];
Rclose=FinancialData["CAT","Close",{{2013,2,16},{2014,3,16}}];

Sopen=FinancialData["SUNS","Open",{{2013,2,16},{2014,3,16}}];
Sclose=FinancialData["SUNS","Close",{{2013,2,16},{2014,3,16}}];

Topen=FinancialData["XOM","Open",{{2013,2,16},{2014,3,16}}];
Tclose=FinancialData["XOM","Close",{{2013,2,16},{2014,3,16}}];

Q[i_]:=If[Qclose[[i,2]]≥Qopen[[i,2]],1,-1]
R[i_]:=If[Rclose[[i,2]]≥Ropen[[i,2]],1,-1]
S[i_]:=If[Sclose[[i,2]]≥Sopen[[i,2]],1,-1]
T[i_]:=If[Tclose[[i,2]]≥Topen[[i,2]],1,-1]

num=Dimensions[Qopen][[1]]

samplespace=Table[{Q[i],R[i],S[i],T[i]},{i,1,num}];

Sort[samplespace];
tallyspace=Tally[%]

p[q_,r_,s_,t_]:=Module[{u},Do[If[{q,r,s,t}==tallyspace[[i,1]],u=N[tallyspace[[i,2]]/num]],{i,1,16}];u]

p[1,1,-1,1]

Sum[p[q,r,s,t],{q,-1,1,2},{r,-1,1,2},{s,-1,1,2},{t,-1,1,2}]

EQS = Sum[p[q,r,s,t]q s,{q,-1,1,2},{r,-1,1,2},{s,-1,1,2},{t,-1,1,2}]
ERS= Sum[p[q,r,s,t]r s,{q,-1,1,2},{r,-1,1,2},{s,-1,1,2},{t,-1,1,2}]
ERT=Sum[p[q,r,s,t]r t,{q,-1,1,2},{r,-1,1,2},{s,-1,1,2},{t,-1,1,2}]
EQT=Sum[p[q,r,s,t]q t,{q,-1,1,2},{r,-1,1,2},{s,-1,1,2},{t,-1,1,2}]

Bellmax=EQS+ERS+ERT-EQT