000			01597naa a2200205uu 4500
001			6032211321321
003			OSt
005			20190211160717.0
008			060322s2006 xx ||||gr |0|| 0 eng d
100	1		_aTRIETSCH, Dan _923520
245	1	0	_aThe effect of systemic errors on optimal project buffers
260			_aAmsterdam : _bElsevier, _cMay 2005
520	3		_aExisting mathematical models for setting buffers for time or cost in project management assume that project activities are statistically independent. This leads to a highly counterintuitive and damaging conclusion that project buffers should become relatively negligible for projects with long chains of activities. We present a model that considers the statistical dependence between activities caused by estimation bias. We show that if relatively high service levels are desired, this imposes a positive lower bound on the buffer as a data-based fraction of the estimated project duration or budget. We also introduce a new approach for collecting data and estimating the parameters necessary to implement the model. This approach places a smaller burden on decision makers than traditional PERT: they provide single point estimates for means, while variance elements and bias correction are computed electronically using historical data.
650		4	_aTempo _916923
650		4	_aCusto _912970
773	0	8	_tInternational Journal of Project Management _g23, 4, p. 267-274 _dAmsterdam : Elsevier, May 2005 _xISSN 0263-7863 _w
942			_cS
998			_a20060322 _b1132^b _cNatália
998			_a20130820 _b0957^b _ckarina
999			_aConvertido do Formato PHL _bPHL2MARC21 1.1 _c15042 _d15042
041			_aeng