The level of analysis detail required for each technique varies in
accordance with the different modes of operations highlighted
above. Techniques that use the direct analysis approach are thus
often termed simplistic methods, while those involving extensive
modifications of the schedules, as in the additive and subtractive
simulations, are termed sophisticated methods (Alkass et al. 1996).
The latter groups tend to give more accurate results than the former
but they require more expense, time, skills, resources, and projectrecords to operate (SLC 2002; Pickavance 2005). The characteristics
of the techniques based on these factors and their relative
reliability as discussed in various text (SCL 2002; Arditi and
Pattanakitchamroon 2006; AACEI 2007) can be summarized in
Fig. 2 (Braimah 2008).