- 上一篇：建筑业由噪音引起的听力损失英文文献和中文翻译
- 下一篇：节能墙体材料数据库和数据分析英文文献和中文翻译
Fixing the costs offered (or fixing a minimum bidprice) by suitable legal contracts and defining appro-priate quality measures could perhaps help mitigatethe adverse consequences of unreasonably low bids.However, in such a case, project administratorsshould adopt a different bid-awarding method (suchas multi-criteria evaluation method rather than thelow-bid method discussed herein) to award projectcontracts, because the bid prices of all bidders willbe the same (when the costs offered are fixed) or willbe very close (when the minimum bid price is fixed).Hence, the bid price is not an appropriate criterion.Additional criteria should be defined for selecting awinner. Hence, the feasibility of fixing the costs orminimum costs for bid evaluation should beaddressed by future research. Because the key evaluation criterion, Dj, is calculatedbased on the value of the estimated unit price of theowner (Oj), it is important to ensure the value of Ojis reasonable. In a poor estimation situation, under-estimating is more likely than over-estimating, basedon experience of public construction projects in Tai-wan [23]. Under-estimation reveals that the owner sproject ceiling price and associated unit prices (Oj)are low. Hence, the difference between the unit pricessubmitted by the owner and the lowest bidder tendsto be small. Consequently, the unit price (Bj) submit-ted by the lowest bidder is unlikely to be treated asunreasonable, unless it is extremely low. Generally,under-estimations favor the lowest bidders. To estab-lish a fair bid evaluation environment, the proposedmodel can be extended to consider only those costitems that have acceptable owner s unit prices. Forinstance, if the owner s unit price (Oj) is between theminimum unit price (minj) and the maximum unitprice (maxj) submitted by other qualified bidders,then Oj is acceptable. Otherwise, Oj is unacceptableand the corresponding cost item j should be excludedfrom the bid evaluations. Although the execution of the proposed model isstraightforward, it should be presented to projectadministrators of public procurement entities andcontractors via conferences, training programs andother means. Conferences and training programsare often held to promote a new administration orderor governmental regulations in Taiwan. Accordingly,the project administrators and contractors will befamiliar with the modeling steps when the model isimplemented. A low bidder can also be a beneficiary because theexecution of the developed model can help to clarifyambiguous tendering documents. A rejected low bid-der may appreciate this model if his unreasonably lowbid price is caused by mistaken estimates. Therefore,both project administrators and bidders should bewilling to accept the proposed bid evaluation model,because it can support a win-win situation.7. ConclusionsThis study proposes a unit-price-based model forevaluating competitive bids. The developed model andexisting models have two similarities; (1) they all con-sider the bid prices submitted by other qualified bidders,and (2) they all allow the second lowest bid to continueto be evaluated if the lowest bid is rejected. However, thepresented model differs in four main ways from theexisting models. First, in the proposed model, the assess-ment of a lowest bid concerns unit prices rather than thetotal bid price (the total bid price is also used a criterionto indicate whether a lowest bid should be further eval-uated). Second, the proposed model evaluates a low bidbased on the unit price data (submitted by the ownerand the other qualified bidders) obtained for the projectof interest rather than from historical data. The use ofdata concerning historical projects to evaluate bids caneasily be challenged, primarily because the quality-re-lated specifications of a particular cost item (even withthe same item name) in different projects may vary, sothe corresponding unit prices of the cost item in variousprojects are also likely to vary. Third, in the developedmodel, the evaluation and clarification steps identifywhich parts of a low bid are unreasonable. The decisionis made according to whether the total unreasonablecost exceeds the total bid price by a predefined thresholdratio. Restated, the accept/reject decisions are not madebased on statistical analyses. Fourth, the clarificationstep in the proposed model enables the low bidder to de-fend suspicious unit prices. Therefore, the low bidderalso participates in the bid evaluation process. Eventu-ally, the low bidder will likely be satisfied with the deci-sion even if he is rejected. Notably, GovernmentProcurement Law in Taiwan mandates such a clarifica-tion step in any proposed bid evaluation model [2].The entire modeling process can be viewed as an elec-tronically facilitated evaluation of the cost allocation ofthe low bid. Although the proposed model may not bedeveloped based on complex mathematical theories, itspractical implications can contribute to current publicprocurement practice, as indicated by several industrialpractitioners in Taiwan. After the lowest bid is consid-ered reasonable (namely, the contract is won), the modelproposed by Wang can be used to revise the unreason-able unit prices to reasonable ones given the fixed totalbid price (that is, to reshuffle the unreasonable costs)[24]. The finalized contractual unit prices then can serve as a mutually agreeable basis for handling future changeorders.