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The final main criteria/attributes of selection of the best bidder/contractor for the implementation of the construction project that resulted from the Delphi survey and PCA third round_
| No. | Criteria | Third round analysis results | PCA results | ||
|---|---|---|---|---|---|
| Mean | SD | KMO | Factor pattern coefficient | ||
| 1. | The technical expertise of the contractor’s current team | 4.5833 | 0.66856 | 0.759 | 0.810 |
| 2. | Previous experience in the project field (similar projects) | 4.5000 | 0.90453 | 0.725 | 0.776 |
| 3. | Contractor bid price | 4.5000 | 0.67420 | 0.775 | 0.727 |
| 4. | Collaboration with other designers and contractors | 4.4167 | 0.51493 | 0.661 | 0.815 |
| 5. | Contractor’s cash flow | 4.4167 | 0.90034 | 0.585 | 0.691 |
| 6. | General experience of the contractor | 4.3333 | 0.65134 | 0.792 | 0.774 |
| 7. | History of legal disputes | 4.3333 | 0.77850 | 0.675 | 0.856 |
| 8. | Technical bid quality and organising | 4.3333 | 0.88763 | 0.598 | 0.526 |
| 9. | Number of failed projects in the contractor’s record | 4.2500 | 0.86603 | 0.579 | 0.679 |
| 10. | Technical approach and work progress program | 4.2500 | 0.96531 | 0.771 | 0.847 |
| 11. | Number and status of the contractor’s current projects (under construction) | 4.1667 | 0.38925 | 0.661 | 0.757 |
| 12. | Financial stability of the contractor | 4.1667 | 0.71774 | 0.674 | 0.770 |
| 13. | Complete projects within the specified time | 4.0833 | 0.79296 | 0.672 | 0.784 |
| 14. | Financial obligations and debts | 4.0833 | 0.90034 | 0.729 | 0.867 |
| 15. | Willingness to offer advice and suggest construction methods | 4.0000 | 0.60302 | 0.546 | 0.322 |
| 16. | Quality systems and cost control | 4.0000 | 0.73855 | 0.695 | 0.803 |
| 17. | Availability of construction equipment and tools | 3.9167 | 0.51493 | 0.708 | 0.560 |
| 18. | The occupational safety program | 3.9167 | 0.79296 | 0.668 | 0.765 |
| 19. | Relationship with the employer or his representative | 3.7500 | 0.62158 | 0.548 | 0.455 |
| 20. | Record of accidents during previous years | 3.7500 | 0.62158 | 0.607 | 0.371 |
| Total | 0.672 | ||||
The occupational information pertaining to experts’ sample in the Delphi survey_
| Experts’ names | Institution name | Work sector | Current position | |
|---|---|---|---|---|
| (1) | A. J. | Buildings Directorate | Public sector | Planning Engineer |
| (2) | S. J. | Al-Mansour General Engineering Company | Public sector | Division Manager |
| (3) | H. M. J. | Al-Arabia Company for Engineering Technologies and Contracting | Private sector | Project Manager |
| (4) | A. M. J. | The General Company for Iraqi Railways | Public sector | Project Manager |
| (5) | A. A. A. | National Center for Engineering Consultancy | Public sector | Depart. Manager |
| (6) | M. W. | Buildings Directorate | Public sector | Planning Engineer |
| (7) | K. W. | Debajeh Engineering Consulting Office | Private sector | Project Manager |
| (8) | H. S. | Buildings Directorate | Public sector | Division Manager |
| (9) | A. M. | Al-Khwarizmi Engineering Consulting Office | Private sector | Project Manager |
| (10) | H. H. | X-Line Engineering Office | Private sector | Project Manager |
| (11) | A. S. | Office Of Externally Funded Projects | Public sector | Division Manager |
| (12) | S. Y. | Buildings Directorate | Public sector | Division Manager |
The experts’ answers on the rank of the competing contractors in the case study_
| Exp. | Alter. | The selection criteria | |||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| C1 | C2 | C3 | C4 | C5 | C6 | C7 | C8 | C9 | C10 | C11 | C12 | C13 | C14 | C15 | C16 | C17 | C18 | C19 | C20 | ||
| RANK | |||||||||||||||||||||
| Exp. 1 | R | 2 | 1 | 2 | 2 | 2 | 3 | 1 | 3 | 2 | 4 | 2 | 2 | 4 | 1 | 2 | 2 | 2 | 2 | 4 | 4 |
| F | 2 | 1 | 2 | 2 | 1 | 2 | 1 | 2 | 2 | 3 | 2 | 1 | 3 | 1 | 1 | 1 | 2 | 1 | 4 | 3 | |
| A | 1 | 2 | 2 | 2 | 3 | 1 | 1 | 1 | 1 | 1 | 3 | 3 | 1 | 2 | 2 | 4 | 1 | 3 | 4 | 2 | |
| B | 3 | 3 | 2 | 1 | 4 | 1 | 1 | 1 | 4 | 2 | 1 | 3 | 2 | 3 | 2 | 3 | 2 | 4 | 4 | 1 | |
| Exp. 2 | R | 2 | 1 | 3 | 2 | 2 | 3 | 1 | 3 | 1 | 1 | 2 | 1 | 3 | 1 | 2 | 2 | 2 | 2 | 4 | 4 |
| F | 1 | 2 | 3 | 2 | 1 | 4 | 1 | 2 | 1 | 2 | 2 | 2 | 3 | 1 | 1 | 1 | 2 | 1 | 4 | 3 | |
| A | 3 | 3 | 3 | 2 | 3 | 2 | 1 | 1 | 2 | 4 | 3 | 3 | 2 | 3 | 2 | 4 | 1 | 3 | 4 | 2 | |
| B | 4 | 4 | 3 | 1 | 3 | 1 | 1 | 1 | 2 | 3 | 1 | 4 | 3 | 2 | 3 | 3 | 2 | 4 | 4 | 1 | |
| Exp. 3 | R | 3 | 1 | 3 | 3 | 2 | 2 | 1 | 4 | 3 | 4 | 2 | 2 | 3 | 2 | 2 | 2 | 3 | 2 | 4 | 4 |
| F | 2 | 1 | 3 | 2 | 1 | 1 | 1 | 1 | 1 | 3 | 2 | 1 | 3 | 2 | 1 | 1 | 3 | 1 | 4 | 3 | |
| A | 1 | 2 | 3 | 4 | 3 | 4 | 1 | 2 | 2 | 1 | 3 | 3 | 1 | 1 | 2 | 4 | 2 | 3 | 4 | 2 | |
| B | 4 | 3 | 3 | 1 | 4 | 3 | 1 | 3 | 4 | 2 | 1 | 4 | 2 | 3 | 3 | 3 | 3 | 4 | 4 | 1 | |
The rank of each alternative in the case study according to bid amount_
| The rank | ||
|---|---|---|
| Contractor name | Bid amount (ID) | Rank |
| R | 2,908,346,500 | 4 |
| F | 2,563,811,500 | 3 |
| A | 2,022,069,000 | 2 |
| B | 2,001,704,000 | 1 |
Some of the contractor selection methods from the literature review_
| No. | Contractor selection methods | Authors |
|---|---|---|
| 1. | MOORA method | Brauers et al. (2008) |
| 2. | A fuzzy neural network approach | Lam et al. (2010) |
| 3. | The ANP | Cheng and Li (2004) |
| 4. | The AHP | Razi et al. (2019) |
| 5. | AHP and TOPSIS model | Othoman et al. (2013) |
| 6. | The PCA method | Lam et al. (2005) |
| 7. | BWM and Fuzzy-VIKOR techniques | Naghizadeh Vardin et al. (2021) |
| 8. | An evidential reasoning approach | Sönmez et al. (2001) |
| 9. | SAW-G and TOPSIS GREY techniques | Zavadskas et al. (2010) |
| 10. | The PIPS | Kashiwagi and Byfield (2002) |
| 11. | COPRAS-G | Zavadskas et al. (2009) |
| 12. | The Fuzzy Sets theory | Plebankiewicz (2014) |
WV of descriptive frequencies (Jeleva et al_ 2017; Mohammed and Jasim 2018)_
| Descriptive frequency | CI | WV |
|---|---|---|
| Very low | 1 ≤ CI ≤ 1.8 | 1 |
| Low | 1.8 < CI ≤ 2.6 | 2 |
| Medium | 2.6 < CI ≤ 3.4 | 3 |
| High | 3.4 < CI ≤ 4.2 | 4 |
| Very high | 4.2 < CI ≤ 5 | 5 |
The final weight of each alternative in the case study_
| Contractor name | Weight |
|---|---|
| R | 0.234803 |
| F | 0.312379 |
| A | 0.249111 |
| B | 0.203858 |
Sets, indices and variables for the OPA method (Ataei et al_ 2020)_
| Sets | |
| I | Set of experts ∀i ∈ I |
| J | Set of attributes ∀j ∈ J |
| K | Set of alternatives ∀k ∈ K |
| Indices | |
| I | Index of the experts (1,..., p) |
| J | Index of preference of the attributes (1,..., n) |
| K | Index of the alternatives (1,..., m) |
| Variables | |
| Z | Objective function |
| Weight (importance) of kth alternative based on jth attribute by ith expert at rth rank | |
| The kth alternative based on attribute j by expert i at rank r |
The final weights of each expert in the case study_
| Expert name | Weight |
|---|---|
| Exp. 1 | 0.589135 |
| Exp. 2 | 0.262262 |
| Exp. 3 | 0.148754 |
The final weights of the selection criteria in the case study_
| Selection criteria | Weight |
|---|---|
| C1 | 0.092762 |
| C2 | 0.10515 |
| C3 | 0.0666 |
| C4 | 0.039449 |
| C5 | 0.022768 |
| C6 | 0.061125 |
| C7 | 0.0478 |
| C8 | 0.029022 |
| C9 | 0.0685 |
| C10 | 0.034672 |
| C11 | 0.077974 |
| C12 | 0.110802 |
| C13 | 0.08656 |
| C14 | 0.044946 |
| C15 | 0.021029 |
| C16 | 0.020759 |
| C17 | 0.021233 |
| C18 | 0.024357 |
| C19 | 0.006592 |
| C20 | 0.018051 |
The scores of each alternative from applying the traditional method in the case study_
| The traditional method (weighted form) | |
|---|---|
| Contractor name | Score |
| R | 80.56 |
| F | 83.36 |
| A | 77.6 |
| B | 68.61 |
The evaluation questions and their answers_
| The questions | Answers | AM | Degree of importance | |||||
|---|---|---|---|---|---|---|---|---|
| V. high (5) | High (4) | Medium (3) | Low (2) | V. low (1) | ||||
| (1) | Is the proposed framework applicable to construction projects? | 3 | 8 | 3 | - | - | 4 | High |
| (2) | Is the sequence of issues in the proposed framework suitable? | 2 | 11 | 1 | - | - | 4.07 | High |
| (3) | Based on your opinion, does the proposed framework contribute towards enhancing decision-making in construction projects? | 1 | 7 | 6 | - | - | 3.64 | High |
| (4) | What do you think about the importance of the proposed framework for your workplace? | 1 | 6 | 3 | 4 | - | 3.28 | Medium |
| (5) | Does the proposed framework deal well with changes and updates? | 3 | 4 | 5 | 2 | - | 3.57 | High |
The experts’ answers on the rank of selection criteria employed for ascertaining the best bidder or contractor_
| No. | Selection criteria of the design consultant | The experts | |||
|---|---|---|---|---|---|
| Exp. 1 | Exp. 2 | Exp. 3 | |||
| Rank | |||||
| C1. | The technical expertise of the contractor’s current team | 3 | 1 | 3 | |
| C2. | Previous experience in the project field (similar projects) | 2 | 2 | 2 | |
| C3. | Contractor bid price | 1 | 3 | 1 | |
| C4. | Contractor’s cash flow | 4 | 3 | 4 | |
| C5. | Collaboration with other designers and contractors | 11 | 4 | 10 | |
| C6. | General experience of the contractor | 3 | 5 | 3 | |
| C7. | History of legal disputes | 3 | 8 | 4 | |
| C8. | Technical bid quality and organising | 11 | 4 | 11 | |
| C9. | Number of failed projects in the contractor’s record | 2 | 6 | 2 | |
| C10. | Technical approach and work progress program | 5 | 5 | 7 | |
| C11. | Number and status of the contractor’s current projects (under construction) | 2 | 2 | 5 | |
| C12. | Financial stability of the contractor | 1 | 3 | 3 | |
| C13. | Complete projects within the specified time | 2 | 1 | 2 | |
| C14. | Financial obligations and debts | 4 | 4 | 8 | |
| C15. | Quality systems and cost control | 7 | 7 | 9 | |
| C16. | Willingness to offer advice and suggest construction methods | 8 | 9 | 12 | |
| C17. | Availability of construction equipment and tools | 6 | 6 | 6 | |
| C18. | The occupational safety program | 9 | 5 | 10 | |
| C19. | Relationship with the employer or his representative | 6 | 10 | 7 | |
| C20. | Record of accidents during previous years | 10 | 9 | 13 | |
The qualifications of the selected experts in the case study_
| No. | The element of evaluation | Experts’ qualification | |||
|---|---|---|---|---|---|
| Exp.1 | Exp. 2 | Exp. 3 | |||
| 1. | 10 ≤ EX < 15 | ||||
| 15 ≤ EX < 20 | √ | ||||
| 20 ≤ EX < 25 | √ | √ | |||
| 25 ≤ EX | |||||
| The Experience Years | 23 | 21 | 17 | ||
| 2. | Has a good relationship with the senior management? | √ | √ | √ | |
| Not have discounts or problems with the work team? | √ | √ | |||
| Has acceptability and the ability to deal with different cultures? | √ | √ | |||
| Has good relations with other parties outside the organization? | √ | √ | |||
| 3. | Has not had an administrative penalty for the past five years? | √ | √ | √ | |
| Has at least five certificates of thanks and appreciation for the past five years? | √ | √ | √ | ||
| has a good professional history characterized by integrity, impartiality? | √ | √ | √ | ||
| Has a recommendation certificate from a previous job? | √ | √ | |||
| 4. | Has no communication and coordination problems in his last three projects? | √ | √ | √ | |
| Has the ability to use communication and coordination programs? | √ | √ | √ | ||
| Has a high level of negotiation and persuasion skills? | |||||
| participation in previous committees in resolving and settling disputes? | √ | √ | |||
| 5. | participation in workshops or training courses in the building evaluation? | √ | √ | √ | |
| Has good experience from previous similar work? | √ | √ | |||
| Has knowledge and ability to use engineering programs? | √ | ||||
| Has published research in the selected field? | |||||
| 6. | 10 ≤ E < 15 | ||||
| 15≤ E < 20 | √ | ||||
| 20 ≤ E < 25 | √ | ||||
| 25 ≤ E | √ | ||||
| The Employment Years | 25 | 23 | 18 | ||
| 7. | BSc. | √ | √ | ||
| High diploma | |||||
| MSc. | √ | ||||
| Ph.D. | |||||
The main criteria and sub-criteria of selection and evaluation of experts/decision-makers and their weights_
| The main criteria | AM | SD | Weight % | Sub-criteria | Weight value | |
|---|---|---|---|---|---|---|
| (1) | Years of practical experience in the field of specialisation | 4.476 | 0.75 | 16.2362 | – 10 ≤ EX < 15 | 0.25 |
| – 15 ≤ EX < 20 | 0.5 | |||||
| – 20 ≤ EX < 25 | 0.75 | |||||
| –25 ≤ EX | 1 | |||||
| (2) | Personal relationships | 4.142 | 0.91 | 15.0247 | – Has a good relationship with the senior management? | 0.25 |
| – Has not had discounts or problems with the work team? | 0.25 | |||||
| – Has acceptability and the ability to deal with different cultures? | 0.25 | |||||
| – Has good relations with other parties outside the organisation? | 0.25 | |||||
| (3) | Good conduct and confidence | 4 | 1 | 14.5096 | – Has not had an administrative penalty for the past 5 years? | 0.25 |
| – Has had at least five certificates of thanks and appreciation during the past 5 years? | 0.25 | |||||
| – Has a good professional history characterised by integrity and impartiality? | 0.25 | |||||
| – Has a recommendation certificate from a previous job? | 0.25 | |||||
| (4) | The ability to communicate and coordinate between parties | 3.857 | 0.91 | 13.9909 | – Has had no communication and coordination problems in his last three projects? | 0.25 |
| – Has the ability to use communication and coordination programs? | 0.25 | |||||
| – Has a high level of negotiation and persuasion skills? | 0.25 | |||||
| – Participation in previous committees in resolving and settling disputes? | 0.25 | |||||
| (5) | Capability for research and development in the field of specialisation | 3.761 | 1.09 | 13.6426 | – Participation in workshops or training courses in the specified field? | 0.25 |
| – Has good experience from previous similar work? | 0.25 | |||||
| – Has knowledge and ability to use engineering programs? | 0.25 | |||||
| – Has published research in the selected field? | 0.25 | |||||
| (6) | Employment years | 3.761 | 1.22 | 13.6426 | –10 ≤ E < 15 | 0.25 |
| – 15 ≤ E < 20 | 0.5 | |||||
| – 20 ≤ E < 25 | 0.75 | |||||
| – 25 ≤ E | 1 | |||||
| (7) | Academic degree (BSc., MSc., Ph.D.) | 3.571 | 1.08 | 12.9534 | –BSc. | 0.25 |
| – High diploma | 0.5 | |||||
| – MSc. | 0.75 | |||||
| – Ph.D. | 1 | |||||