Critical Determinants of Public Construction Tendering Costs

Transcription

1 International Journal of Architecture, Engineering and Construction Vol 7, No 1, March 2018, Critical Determinants of Public Construction Tendering Costs Ibrahim Mahamid Department of Civil Engineering, Faculty of Engineering, University of Prince Mugrin, KSA Abstract: This study is conducted to assess and rank cost-influencing factors of construction projects at the pre-tender stage for public construction projects in the West Bank in Palestine. 43 factors affecting pretender cost estimate were identified through literature review and discussion with some construction experts. The factors were tabulated in a questionnaire form and a questionnaire survey included 32 consultants and 21 owners was performed. The study finds a strong agreement between owners and consultants in ranking cost-influencing factors of public construction projects, the top ranked factors a re: client s evaluation and awarding policy, labor skills, tender selection method (open, selected, negotiation, etc.), method of procurement (design bid build, design and build, project management, etc.), clear scope definition f or t he c lient, m aterial p rice changes, estimating method used, and time between project design and project execution. The study extends previous research into factors affecting pre-tender construction cost estimates, by owners and consulting firms w ho p rimarily d eal w ith c osts rather than relying on the judgements of project managers for the identification o f f actors a ssociated w ith c ost o verruns. Both owners and consultants are recommended to focus on the main factors identified i n t his s tudy t o d evelop e ffective strategies for accurate cost estimating, which would ultimately lead to successful projects. Keywords: Pretender, cost estimate, accuracy, owners, consultants, public construction DOI: 1 INTRODUCTION The construction industry is one of the main sectors that provide important ingredients for the development of an economy. It is a tool that helps a society to achieve its goals of urban and rural development. One of the most important construction management functions is estimating process. It is the process of calculating and analyzing all the costs which will enter into a particular job and arriving at a total. In nearly all contract types, the preparation of a realistic cost estimate is a necessary part of any construction operation (Holm et al. 2005). The success or failure of a project is dependent on the accuracy of estimates. Pre-tender estimating is usually carried out by consultant on behalf of his client and is an attempt to forecast contractor tender sum before the design is finalized or before tenders are received (Odusami and Onukwube 2008). For consulting firms, cost estimate is considered as the task that guarantees success, if done properly, or failure if done casually. The failure may not only affect the present project but could drive the firm involved out of business (Shash and Ibrahim 2005). For construction clients, early cost estimate is an important issue that enable them to take a right decision regarding the feasibility of proposed project prior to site acquisition and commitment to build. It is therefore important that the estimate should be as accurate as possible. To prepare accurate pretender cost estimate, very first and most important step is to identify and understand the factors that might affect its accuracy. Hence, this paper is conducted to identify various factors influencing accuracy of pretender cost estimate of public construction projects. The study is performed in the West Bank in Palestine to address the relative severity of the factors affecting accuracy of pretender cost estimate from owners and consultants perspectives through a questionnaire survey. The study extends previous research into factors affecting pretender construction cost estimates, by owners and consulting firms who primarily deal with costs rather than relying on the judgements of project managers for the identification of factors associated with cost overruns. Both owners and consultants are recommended to focus on the main factors identified in this study to develop effective strategies for accurate cost estimating, which would ultimately lead to successful projects. 2 OBJECTIVES The main objectives of this study include the following: 1. To identify the factors affecting accuracy of pretender cost estimate of public construction projects in Palestine. 2. To assess the relative severity of the identified factors from public owners and consultants perspectives. 3. To test the agreement on the score mean of the identified factors among respondents (owners and consultants). *Corresponding author. imahamid@ymail.com 34

2 4. To formulate a number of recommendations to bridge the gap between the different perceptions thus improving the ability of estimators, in Palestine and other developing countries, to prepare accurate pretender cost estimate. 3 LITERATURE REVIEW 3.1 Size of Schedule Delay in Construction Projects The construction industry is at or near the top in the annual rate of business failures and resulting liabilities compared to other industries (Chapman 2001). This is because it is a risky business with too many uncertainties that management has to deal with Enshassi and Abu Mosa (2008). The management of risks is a central issue in the planning and management of any venture. The process of taking a project from initial investment into use is a complex process (Enshassi et al. 2009). In Palestine, the construction industry a basic role in providing homes, public facilities and infrastructure for economic enterprises, and in improving the Palestinian national economy as a whole (Mahamid et al. 2012). For example, the Gross domestic capital formation in the Palestinian territories rose from US$10.8 million to US$520.3 million between 1968 and 1987 and this was primarily attributable to the contribution of the construction industry, which ranged 43 82% during the same period (UN 1994). However, this industry suffers from a number of problems that affect time, cost and quality performances and lead to prevent it from assuming its big role in the Palestinian economy as is the situation in neighboring and developing countries (Enshassi et al. 2006). Mahamid (2013) investigated the cost deviation in 74 road construction projects awarded in the West Bank in Palestine over the years He found that the average of cost deviation of value 16.73%, ranging from % to 56.01%. Some of the problems faced by the Palestinian construction industry were summarized by Al-Najjar (2008), namely: 1. Large number of workers in comparison to the number of projects 2. Borders closure and shortage of materials in markets 3. Dependency on Israel and other countries in getting construction materials 4. Continued increase in material prices 5. Dependency on donor countries to get the fund of implemented projects in Palestine 6. Unstable economic situation and its correlation with Israeli one 7. Unstable political situation Regarding the factors affecting cost estimate of construction projects, many studies have been performed to investigate cost overrun in construction projects. However, the pretender cost estimate has not seen the same level of attention. Flyvbjerg et al. (2003) investigated the cost deviation in 258 transportation infrastructure projects. The projects were located in 20 nations on 5 continents, including both developed and developing nations. Some of the main study findings are: (1) Cost escalation is a global phenomenon, (2) Cost escalation has not decreased over the past 70 years. In the same study, the author conducted a questionnaire survey to investigate the impact of projects physical characteristics on cost deviation in road construction. Mahamid (2013) conducted a study to investigate the relation between cost deviation and project factors in road construction projects implemented in the West Bank in Palestine. The study concluded the followings: (1) Project size has high impact on cost deviation in road construction, (2) Soil and rock suitability has moderate impact on cost deviation in road construction, (3) Soil and rock drill ability has moderate impact on cost deviation in road construction, (4) Terrain condition has moderate impact on cost deviation in road construction. Koushki et al. (2005) conducted a questionnaire survey to address the factors affecting cost estimating in construction projects in Kuwait. They study concluded that the critical cost variation factors are: contractor-related problems, material-related problems and owners financial constraints. Al-Zarooni and Abdou (2000) identified variations in UAE building projects estimates. They found that the variations between feasibility and contract cost, ranging between -28.5% and +36%. They stated that the budgeting using a Single Unit Estimating basis played a major role in such variations. Memon et al. (2011) addressed the critical factors affecting accuracy of construction cost in Malaysia through a questionnaire survey. They found that the top affecting factors are: poor design and delays in design, unrealistic contract duration and requirements imposed, lack of experience, late delivery of materials and equipment, relationship between management and labor, delay preparation and approval of drawings, inadequate planning and scheduling, poor site management and supervision, and mistakes during construction. 67 construction projects around the world were analyzed by Oberlender and Trost (2001) to identify the main factors affecting accuracy of early stage estimates. 45 factors were addressed which grouped into 11 orthogonal elements. The study concluded that the top five important factors include: process design, team experience and cost information, time allowed to prepare estimates, site requirements, and bidding and labor climate. Mahamid (2014) identified the cost estimating factors in Palestinian building construction projects. He concluded that the top five affecting factors are: fluctuation in currency exchange rate, project financing, contract management, level of competitors, and cost of materials. 64 factors were considered in a questionnaire survey to address the critical factors affecting accuracy of pretender cost estimate in Gaza Strip by Abdal- Hadi (2010). The study concluded that the top factors are: material (prices/availability/supply/quality/imports), closure and blockade, project team s experience in the construction type, the experience and skill level of the consultant, clear and detail drawings and specifications, quality of information and flow requirements, completeness of cost information, accuracy and reliability of cost information, currency exchange fluctuation, and finally clear contract conditions. In Nigeria, Odusami and Onukwube (2008) investigated the critical factors affecting accuracy of consultant pre-tender cost estimate from the perspective of quantity surveyors through questionnaire survey. They concluded that the main affecting factors are: expertise of consultants, quality of information and flow 35

3 requirements, project team s experience of the construction type, tender period and market condition, extent of completion of pre-contract design, complexity of design and construction, availability and supplies of labor and materials. Frimpong et al. (2003) studied 26 factors affecting cost accuracy in construction of ground water projects in Ghana. The overall ranking results indicated that all participants agreed on the most critical factors, namely: poor contractor management, monthly payment difficulties, material procurement, poor technical performances, and escalation of material prices. Elhag et al. (2005) performed a questionnaire survey in UK to address cost-influencing factors of construction projects at the pre-tender stage for building projects from perspective of quantity surveyors. The identified factors were categorized into 6 groups, namely: client characteristics, consultant and design parameters, contractor attributes, project characteristics, contract procedures and procurement methods, and external factors and market conditions. They concluded the followings: 1) construction project costs were more affected by architects and consultants than by contractors. 2) there is a strong agreement between quantity surveyors in ranking costinfluencing factors of construction projects, 3) the top ranked category of factors was consultant and design parameters, followed by: client characteristics, project characteristics, external market conditions, contract procedures and procurement methods, and contractor attributes. To have a general view about the critical determinants of construction cost, Table 1 summarizes the findings of the previous studies investigated. It can be seen that most of the factors affecting the pretender cost estimate are related to project resources (labor, equipment and materials), followed by consultants and design and contract and tendering. The above examples demonstrate that the accuracy of pretender cost estimate in construction projects is alarming problem and more attention should be paid to this problem. This study is conducted to identify a comprehensive list of factors affecting accuracy of pretender cost estimate in construction projects. Following this, the paper reports on the findings of a survey targeting project public owners and consultants, in an attempt to shed some light on how each project party perceives the relative severity of these factors. Finally, the paper formulates a number of recommendations in order to bridge the gap between the different perceptions thus improving the level of cost estimate in construction projects. 4 RESEARCH METHOD A survey questionnaire with the objective of determining the major factors influencing accuracy of pretender cost estimate of public construction projects had been conducted. The dependent factor of this study is the accuracy of pretender cost estimate in public contracts. The independent factors are the 43 factors that affect pretender cost estimate accuracy. The similar factors were classified under one category; 6 categories were used: client related factors, consultants and design related factors, contract and tendering related factors, project characteristics related factors, cost estimating related factors, and market conditions (labor, materials, equipment) related factors. In order to ensure the appropriateness of the respondents feed back to the objectives of this study, a pilot study was carried out. Three experts were involved to check the questionnaire validity. Based on their feedback, slight modifications were done. The survey questionnaire is developed to assess the perceptions of the public owners and consultants of the relative severity of factors influence the accuracy of pretender cost estimate and measure differences in collective perspectives and any possible popular misconceptions or prejudices. Next, the questionnaire was distributed to a random sample of public owners and consultants, in the field of public construction projects in Palestine. Responses to the questionnaire were then collected and analyzed. The analysis of the questionnaire included ranking of the different responses according to their relative importance for public owners and consultants. Furthermore, a one-way ANO- VA was carried out among the means of responses of the two groups for each individual factor to measure for any significant differences among the respondents perceptions. Discussion of the results was based on personal interviews that were conducted to clarify responses. Interviewees were experts from the Ministry of Public Works and the Palestinian Association of Construction contractors, and some private construction consultancy firms. The scope of this research includes public construction in the Table 1. The main factors affecting construction cost estimate as presented in some selected previous studies Author Country Project Client Consultants Cost Contract and Resources (labor, of study factors factors and design estimating tendering equipment and material) Mahamid (2013) The West Bank - Palestine Koushki et al. (2005) Kuwait Al-Zarooni and Abdou (2000) UAE Memon et al. (2011) Malaysia (67 Construction Oberlender and Trost (2001) projects around the world) Mahamid (2014) The West Bank-Palestine Abdal-Hadi (2010) Gaza Odusami and Onukwube (2008) Nigeria Frimpong et al. (2003) Ghana Elhag et al. (2005) UK 36

4 West Bank in Palestine. In this research, sampling was necessary because it would be practically impossible to conduct a census to rank factors affecting pretender cost estimate by all elements of the population. The population consists of all the consultants, and owners (i.e. municipalities and ministries) who are involved in public construction projects. A simple random sampling was chosen to assure that each element in the population has an equal chance of being included in the sample. The sample size was selected based on the judgment of the researcher taking into consideration the proportional to the relative population size. Finally a sample of 40 and 30 owners were selected to fill the questionnaire. The questionnaires were distributed and collected through direct interview (by hand), fax, and . Returned questionnaires consisted of 32 consultants and 21 owners representing a response rate of 70% and 80%, respectively. This response rate was achieved by continuous and close contact with public owners and consultants for 4 months. The respondents were asked to express their perception, in terms of severity of the pretender cost estimate factors stated in the questionnaire. The respondents were asked to give their opinion on the severity of each factor based on a five-point Likert scale. The scale and the weight given to each response are shown in Table 2. Table 2. Severity weighting scale in the research survey Severity scale Very High High Moderate Low Very low severe Severe severe severe RESULTS AND DISCUSSION 5.1 Ranking of s and Discussion The ranking of factors affecting the accuracy of pretender cost estimate was determined by taking the respective severity index of the reported score data for all the respondents. The resulting severity index and corresponding ranks are presented in the following sections Client Related s Table 3 shows the relative severity index (RII) and ranking of each factor under the client group from owners and consultants views. 5 factors are considered under this group. Results indicate that both owners and clients gave the same rank for the considered factors under this group. They ranked client s evaluation and awarding policy in position 1, followed by clear scope definition for the client, communication and coordination with consultants, client experience in construction projects, and financial conditions of the client, respectively. It can be seen that both owners and consultants realize that awarding project to lowest bid price (awarding policy) is a critical issue and should be improved such that project should not be awarded to the lowest bidder but to the most suitable bidder who is technically and financially sound. This result was not concluded as a critical factor by any of the investigated studies. Table 3. Ranking of client related factors Client s evaluation and awarding policy Clear scope definition for the client Communication and coordination with consultants Client experience in construction projects Financial conditions of the client Consultants and Design Related s The relative severity index (RII) and rank of factors related to consultants and design are summarized in Table 4. Seven factors are listed under this group. The experience and skill level of the consultant has been ranked by the owners respondents in the first position. However, this factor has been ranked by the consultants respondents in the second position. This result is in line with many of the investigated studies (Memon et al. 2011; Abdal-Hadi 2010; Odusami and Onukwube 2008; Oberlender and Trost 2001). Table 4. Ranking of consultants and design related factors Clear and detailed drawings and specifications Communication and coordination between designers Communications with client Communications with suppliers Designer s experience level The experience and skill level of the consultant Volume of consultant s workload during estimation Consultants input indicates that communications of consultants with suppliers is the top factor affecting accuracy of pretender cost estimate in public construction projects. However, this factor has been ranked by the owners respondents in the second position. Communication between consultants and suppliers is a key issue for well prepared estimate, since it keeps the estimator updated with new prices, products and construction technologies. This result is not in agreement with any of the investigated studies. The top three factors from each view is highlighted in red color and the bottom three factors are highlighted in green color as shown in the table below. Results show that the ranking from owners and consultants views is quite similar, but they 37

5 have significant difference in the ranking of: communications with client ranked 3 by owners and 6 by consultants, volume of consultant s workload during estimation ranked 7 by owners and 3 by consultants s Related to Cost Estimating The relative severity index (RII) and rank of factors related to cost estimating are summarized in Table 5. Seven factors are listed under this group. Inputs of owners and consultants underline that estimating method used is the top severe factor negatively affecting accuracy of pretender cost estimate in public construction. This result is justified, as the early estimates of public construction projects are usually budgeted using a Single Unit Estimating (cost per square meter) basis, regardless of the nature of projects and their associated risks or the construction complexity and buildability. This result is in line with Al-Zarooni and Abdou (2000). Availability of data base of bids on similar project (historical cost data) has been ranked in position 2 by both owners and consultants. This indicates that both participants realize that a well-established cost data bank is very important for wellprepared cost estimate in the early project stages. Abdal-Hadi (2010) and Oberlender and Trost (2001) are in agreement with this result, as the lack in historical cost data affects the cost estimate accuracy. Table 5. Ranking of factors related to cost estimating Accuracy and reliability of cost information Availability of data base of bids on similar project (historical cost data) Completeness of cost information Estimating method used Estimator s experience Procedure for updating cost information Time allowed for preparing the cost estimate The top three factors from each view is highlighted in red color and the bottom three causes are highlighted in green color as shown in the table below. Results indicate that the ranking of factors under this group from owners respondents and consultants respondents is quite similar s Related to Project Characteristics Table 6 shows the relative severity index and ranking of factors related to project characteristics. 4 factors are identified under this group. Owners input indicates that the top affecting factor under this group is project duration, followed by site conditions, project location, and project size, respectively. While consultants input indicates the following factor ranking: project duration in 1st position, project size in 2nd position, site conditions in 3rd position, and project location in 4th position. It can be seen that project duration is the most critical factor for both parties because as project going on, series of unexpected changes may arise, especially when the project duration is long. These changes might affect project cost. Mahamid (2014) is in agreement with this result, as the project duration affects the cost estimate accuracy. Table 6. Ranking of factors related to project characteristics Location of project Project duration Project size Site conditions (topography, access,..etc) s Related to Contract and Tendering Table 7 shows the relevant severity index and ranking of factors related to contract and tendering. 9 factors are identified under this group. Tender selection method (open, selected, negotiation, etc.) has been ranked by the owners respondents in the 1st position. However, this factor has been ranked by the consultants respondents in the 2nd position. This result can be justified, as the method of contractor selection affects cost performance. For example: in open tendering, the owner usually selects the bidder with lowest price, while he may not select the lowest bidder in other tendering methods such selected or negotiation tendering. As explained above, the Table 7. Ranking of factors related to contract and tendering s Advanced payment Level of competitors in the tendering Method of procurement (design bid build, design and build, project management, etc.) Number of competitors in the market Tender selection method (open, selected, negotiation,..etc.) The taxes and other financial requirements on tender Time between project design and project execution Timing of advertisement ( weather effects) Type of contract lowest bidder might be a contractor with low capabilities and poor cash flow that may lead to poor cost performance. This result is not supported by any of the investigated studies. 38

6 Time between project design and project execution has been ranked by the consultants respondents in the 1st position. However, this factor has been ranked by the owners respondents in the 2nd position. This result is justified, as many changes that may affect cost estimate will arise when the duration between design phase and execution phase is long such as changes in material prices, fluctuation in currency exchange, materials availability, labor and equipment rates, etc. This result is not in line with any of the investigated literature. Table 7 shows the top three factors from each view in red color and the bottom three factors in green color low. Results show that the ranking from owners and consultants views is quite similar, but they have significant difference in the ranking of: type of contract ranked 8 by owners and 4 by consultants, and number of competitors in the market ranked 4 by owners and 7 by consultants s Related to Market Conditions Table 8 illustrates the relevant severity index and ranking of factors related to market conditions. 11 factors are listed under this group. Labor skills has been ranked by owners respondents and consultants respondents in 1st position and 2nd position, respectively. This result is justified, as lack of labor skills affects his productivity which affects accuracy of cost estimate. Another factor concluded as a very important one for both participants is material price changes which has been ranked by owners respondents in 2nd position and by consultants respondents in 1st position. Material price might be affected by many unexpected changes such as: market conditions, supply and demand, availability, quality, national and international economics, exchange rate fluctuation, etc. These all may lead to inaccurate pretender cost estimate. Frimpong et al. (2003), Mahamid (2014), Koushki et al. (2005) and Abdal-Hadi (2010) are in agreement with this result, as changes in material prices affect cost estimate accuracy. Table 8. Ranking of factors related to market conditions s Equipment availability Equipment conditions Equipment costs Equipment efficiency Labor availability Labor costs Labor productivity Labor skills Material price changes Material shortage Material storage Equipment efficiency and labor productivity have been ranked by the owners respondents in the 3rd position and 4th position, respectively. However, these factors have been ranked by the consultants respondents in the 4th position and 3rd position, respectively. This result is acceptable, as labor productivity and equipment efficiency play a key role in determining the financial success of a project. Interviews with some construction participants indicate that labor productivity in Saudi public construction projects might be affected by many factors such as: financial status of contractors and owners, bad relation between labors and management team, low labor rates, lack of training sessions, and lack of labor experience. Table 8 shows the highlighted top three factors under this group in red color and the highlighted bottom three factors in green color. Results show that the factors ranking from owners and consultants views is quite similar, but they have significant difference in the ranking of the following factors: equipment conditions ranked 5 by owners and 9 by consultants, and labor availability ranked 10 by owners and 7 by consultants. 5.2 Overall Ranking Table 9 illustrates the top significant factors affecting accuracy of pretender cost estimate in public construction projects according to owners and consultants. Input of consultants underlines that the top three affecting factors are: material price changes, estimating method used, and labor skills, respectively. While Owners input indicates that the top three factors affecting accuracy of pretender cost estimate are: client s evaluation and awarding policy, labor skills, and tender selection method, respectively. Table 9. Critical factors of construction tendering costs Client s evaluation and awarding policy Labor skills Tender selection method (open, selected, negotiation, etc.) Method of procurement (design bid build, design and build, project management, etc.) Clear scope definition for the client Material price changes Estimating method used Time between project design and project execution 5.3 Groups Ranking The factors affecting accuracy of pretender cost estimate in public construction projects are grouped into 6 groups. Ranking of these groups associated with degree of severity by owners and consultants is presented in Table 10. Table 10 shows that the top three groups affecting accuracy of pretender cost estimate in public construction projects from owners view are: clients related factors, contract and tendering factors, and cost estimating factors, respectively. Consultants, like owners, assign clients related factors as a top group affecting accuracy of pretender cost estimate in public construction projects, followed by cost estimating factors and factors related to market conditions, respectively. 39

7 Table 10. Main groups ranking Group s related to clients s related to cost estimating s related to market conditions s related to contract and tendering s related to consultants and design s related to project characteristics 5.4 Difference in Perception among the Two Groups In order to check for any significant differences among the consultants and public owners perceptions regarding the severity of the factors affecting accuracy of pretender cost estimate for public construction projects, a one-way analysis of variance was conducted among the means of responses from the two groups. The mean values under the two groups, F statistics, and the P values at which hypothesis of equality of mean values among the two groups could be rejected were calculated (Table 11). The results show that there were statistically nonsignificant differences among the respondent groups over the factors affecting pretender cost estimate accuracy; the measured F value for each factor is less than tabular critical F value at the 0.05 level for 1 and 52 of freedom of freedom is approximately (3.20), indicating a strong agreement among the two groups. Figures 1-3 show the results of the one way ANOVA analysis of the top three affecting factors as assessed by the contractors (Figures: 1-3), namely: (1) Client s evaluation and awarding policy, (2) Labor skills, (3) Tender selection method (open, selected, negotiation, etc.). The ANOVA results show that the means of the different groups are not significantly different from one another (measured F s = 1.33, 0.69, 1.02) while the tabular critical F values at the 0.05 level for 1 and 52 of freedom are 5.31, 4.74, and 5.98 respectively. Consequently, there is no need to carry out the analysis any further by using Duncan Multiple Range Test or Scheffe s Test to detect where exactly the mean differences lie since differences are negligible. So, it becomes clear that the above mentioned factors in Table 9 are by consensus of all respondents the critical determinants of public construction tendering costs in Palestine. 6 SUMMARY AND CONCLUSION The factors affecting accuracy of pretender cost estimate in the Palestinian public construction projects are discussed in a field survey. The relative severity index of each factor is calculated based on public owners and consultants respondents. 43 factors are identified through research. The identified factors are combined into 6 groups. The field survey included 21 Table 11. s overall average, P-value, and F-value Overall average F-value P-value Accuracy and reliability of cost information Advanced payment Clear and detailed drawings and specifications Clear scope definition for the client Client experience in construction projects Client s evaluation and awarding policy Communication and coordination between designers Communication and coordination with consultants Communications with client Communications with suppliers Completeness of cost information Designer s experience level Equipment availability Equipment conditions Equipment costs Equipment efficiency Estimating method used Estimator s experience Financial conditions of the client Labor availability Labor costs Labor productivity Labor skills Level of competitors in the tendering Location of project Material price changes Material shortage Material storage Method of procurement (design bid build, design and build, project management, etc.) Number of competitors in the market Procedure for updating cost information Project duration Project size Site conditions (topography, access, etc.) Tender selection method (open, selected, negotiation, etc.) The experience and skill level of the consultant The taxes and other financial requirements on tender Time allowed for preparing the cost estimate Time between project design and project execution Timing of advertisement (weather effects) Type of contract Volume of consultant s workload during estimation 40

8 Figure 1. One-way ANOVA for client s evaluation and awarding policy pretender cost estimate in public construction projects. The statistical analyses of the data show the followings: (1) No participant response specify any of the identified factors with low influence on accuracy of pretender cost estimate, (2) The minimum factor index is 50.57, (3) The minimum groups index is 58.07, (4) The ANOVA analysis results show that there were statistically non-significant differences among the respondent groups over the identified factors. These all indicate that the identified factors are highly relevant to the problem of pretender cost estimate of public construction projects in Palestine. Based on the findings of this study, the following general points are recommended to improve pretender cost estimate of public construction projects in Palestine: (1) Continuous communication and coordination between project participants are required through all project phases, (2) Continuous training sessions should be conducted to improve estimators skills, (3) Estimators are recommended to take the nature of projects and their associated risks into consideration at the time of cost estimating, (4) Owners are recommended to shorten the duration between project design and project execution. Finally, although this study is specific to the country of Palestine, its results can be applicable to other developing countries facing similar problems in their public construction projects. This research could be used as an avenue for other researchers to conduct additional studies on construction cost estimate. Figure 2. One-way ANOVA for labor skills public owners and 32 consultants. Input of consultants underlines that the top three affecting factors are: material price changes, estimating method used, and labor skills, respectively. While Owners input indicates that the top three factors affecting accuracy of pretender cost estimate are: client s evaluation and awarding policy, labor skills, and tender selection method, respectively. Both owners and consultants specify client related factors as the severe source affecting accuracy of Figure 3. One-way ANOVA for tender selection method REFERENCES Abdal-Hadi, M. (2010). s affecting accuracy of pretender cost estimate in Gaza Strip. Master Thesis, The Islamic University of Gaza-Palestine, Gaza, Palestine. 41

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