Wunderink, S.

demand distribution service level level service quantity / european journal stock point period method number value probability variance function system table expression approach section research fferent deviation result time l krever european demand quantities simulation order service levels point r 342–358 journal demand approach approximation density inventory assumption interval estimate variable formulae period demand example time intervals store gamma distribution review systems di fferent period demand approach finition customer fqn 6 qs gamma length distribution function f model request parameter combination ± deviation approximation rapp management demand patterns inventory management fi rst arrival poisson distribution series silver notation period t measurement periods di fferent methods information demand process john wiley unsatis fied requests