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Estimating the required CPU burst
nBut recent instances are more likely to reflect future behavior
nA common technique for that is to use exponential averaging
uS[n+1] = a T[n] + (1-a) S[n]  ;    0 < a < 1
umore weight is put on recent instances whenever a > 1/n
nBy expanding this eqn, we see that weights of past instances are decreasing exponentially
uS[n+1] = aT[n] + (1-a)aT[n-1] + ... (1-a)^{i}aT[n-i] +
                ... + (1-a)^{n}S[1]
upredicted value of 1st instance S[1] is not calculated; usually set to 0 to give priority to to new processes
u