An Alternative Approach If you have a sufficient history & thedemand is relatively stable over time,then use an empirical distribution In the case Sport Obermeyer (Simchi-Levi's textbook)
An Alternative Approach • If you have a sufficient history & the demand is relatively stable over time, then use an empirical distribution • In the case Sport Obermeyer (SimchiLevi’s textbook)
An Example: Demand for a Weekly Magazine in thepast 52 weeks (Computer Today)7998415191222119061411111018141289584174181415699719101215151681111181517191414171213
An Example • Demand for a Weekly Magazine in the past 52 weeks (Computer Today) 15 19 9 12 9 22 4 7 8 11 14 11 6 11 9 18 10 0 14 12 8 9 5 4 4 17 18 14 15 8 6 7 12 15 15 19 9 10 9 16 8 11 11 18 15 17 19 14 14 17 13 12
Frequency Histogram654 32OA69101OA1o?202ActualDemand
Frequency Histogram 0 1 2 3 4 5 6 7 0 2 4 6 8 10 12 14 16 18 20 22 Actual Demand Weeks
Continuous Distribution65rana4326806C24246802222288-Demand
Continuous Distribution 0 1 2 3 4 5 6 7 -6 -4 -2 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 Demand Frequency
Normal Distribution Parameters(mu, sigma^2):μ ~ D = 11.730~s=4.74
D =11.73 s = 4.74 Normal Distribution Parameters (mu, sigma^2):