Dear MarizaTsakalerou, Damianos Efthymiadis & AlmatAbilez

I have read your paper

An intelligent methodology for the use of multi‑criteria decision analysis in impact assessment: the case of real‑world offshore construction

Here are some of my comments:

It seems to me that there is not a clear understandingof MCDM process

1- In page 2 you say: “The term Multi-Criteria Decision Analysis (MCDA) encompasses the wide-ranging family of systematic and transparentmethods providing for the rational differentiating between a range of options, based on a set of criteria, against which each option is assessed”.

Transparent methods? Some of them are, but most are a set of assumptions and subjectivities without any mathematical support, and what is worse, depending on the DM intuitions and mood. Where is the rationality and transparency?

In page 2 “The molding of multiple perspectives from different stakeholders into a single collective choice is based on the values and preferences of the decision makers who are not necessarily (or exclusively) of the construction firm”

In my opinion, modelling the different stakeholders’ perspectives in a single choice is unrealistic. Are you saying that it is for DM preferences, to decide between different stakeholders in conflicting issues? It means that the DM most be at the same time an engineer, account, lawyer, sales manager, etc.

Wouldn’t it be more logical that each stakeholder expresses his/her ideas independently of the others, and then, finding a MCDM method that considers them all and reach an equilibrium? It is like a voting system.

Suppose that the construction manager says that he needs three additional engineers, for concrete, steel and sidings, and the financial manager says that there are not funds for that, but he spends a lot of money in a new informatic system that provides better financial statement. Is the DM able to judge about that? Of course not.

A good MCDM method can instead give a fair, convenience or compromise solution that satisfies everyone. Does this method exist? Sure thing, and it is more that 70 years old.

You say “A typical MCDA method evolves along five structured stages: (i) defining the decision problem, goal, or objective; (ii) determining the criteria and the constraints”

Sorry, your points i, ii and iii are inexact. MCDM methods do not determine criteria; the give results based on alternatives, criteria and values inputted. There is not an algorithm to determine criteria.

2- “subjective preferences of the stakeholders”?

Real problems are not based on preferences but in real data. There are many and very important stakeholders demands and that must be seriously considered. Do you think that the determination of the return of a project depends on preferences, and arbitrarily is fixed say in 11 %, or it depends on a through and deep analysis and forecasts of facts, including risks?

3- In page 4 “and the dimensions of the performance matrix kept to a minimum”

Why? Because the overload or limitation of a MCDM method? A scenario can’t be restricted for considerations of workload. A method must adapt to reality, not the other way around.

In my opinion it is not for the DM to determine the size of the matrix. It is defined by the nature and complexity of the problem

In page 4 “Practical difficulties arise when: The stakeholders do not have basic skills in mathematical concepts and data aggregation methodologies to appreciate the nuances in MCDA; or the stakeholders do have the skills to understand the subjectivity inherent in MCDA, leading to fears that the manipulation of criteria and weights may privilege certain choices over others”

In my opinion, there are not practical difficulties.

It is like saying that a person can’t drive a car if he/she does not know the intricacies of the engine thermodynamics. As far as I know that us not required in driving test.

The stakeholders don’t need to know MCDM. They have to supply the DM what they think is related the project within each specialty.

The Stakeholders don’t need to understand weights or calculate them, it is not their function. The decision matrix must incorporate ALL the stakeholders concerns and in the different fields. Each stakeholder must be concerned with his own department even knowing that some of his demands will be challenged and even opposite to other. Leave the MCDM method to solve and work with contradicting demands from stakeholders. That is what they have been designed for

4 – In page 8 “The results of this -admittedly arbitrary- elimination strategy are highlighted in”

Yes, it is, and therefore, subject to personal decisions. Not really a sophisticated procedure for a problem like this.

I hope these few comments may help

Nolberto Munier