# 125

Dear Nelson Kevin Sinisterra-Solís , Neus Sanjuan , Javier Ribal , Vicent Estruch , Gabriela Clemente , Stelios Rozakis

I have read your article

Developing a composite indicator to assess agricultural sustainability: Influence of some critical choices

My comments

1- In page 2 you say “Overall, each dimension can be defined using different attributes, enabling tradeoffs between and within them. A trade-off implies that a disadvantage in one attribute can be offset by an advantage in another”

If you allow me, you are talking about criteria, not about attributes, because attributes are the characteristics of the values in each criterion, that is, they can be negative or positive, with low or high discrimination, etc. Consequently, trade-offs apply to criteria not to attributes

As you say in the next paragraph and working normatively, the trade-off must be zero. Precisely, because we are working normatively, no compensation and therefore no trade-offs

You say “Nevertheless, supported by scientific evidence and based on the precaution principle (UN, 1992), under a positive view, strong sustainability implies a deeply held conviction of applying limits to the substitution between natural capital and manufactured one”

In sustainability there are not rates of substitution. Of course, there must be limits in each criterion but it does not mean substitution. I must establish a limit for maximum amount of noxious gases, based on international or national standards, and another limit for instance to maximize investment in public health, and another for minimum working capital cost, etc. For instance, in a project for construction of a gas fired electrical power plant, there must be a maximum limit for methane emissions, but increasing that limit does not necessarily mean that I will have more money to build a new hospital. That saving may go to an y other criterion of shared by several. There must be a balance that contemplates multiple objectives, and thus, we cannot consider them independently, which does not imply compensation.

By the way, you do not consider externalities in the use of natural capital, like mining, and oil refinery.

2- In page 2 “The growing increase in this type of tools has awakened the concern of researchers about how to choose among them considering normative, systematic and procedural aspects”

Agreed in a 100 %

3- In page 2 “assigning the importance of the attributes (weighting) in a normative or positive way, with different treatment of the compensation between attributes when the tool includes an aggregation step, that can be classified attending to the type of data (quantitative, qualitative or both) and the sources used (e.g. database and surveys)”

4-Sorry, this is not clear: You mix attributes with criteria. Again, attributes are the characteristics that each criterion has regarding the values it contains. Therefore, you assign weights to criteria, not to attributes. If for weighting you are considering objective weighting like those for entropy, CRITIC or Standard Deviations, they are used to evaluate alternatives, but not if you are thinking in subjective weights - unless they come from a pool or survey – as those invented weights coming from pair-wise comparisons. That is not normative but descriptive.; they simply

reflect what the DM wants, wishes or feels.

II do not understand when you speak about compensation, because then you are considering trade-offs, when they are absurd in sustainability. You cannot compensate for instance the decrease of noxious gases from a plant with an increase in costs in generation equipment

5- In page 2 “In this respect, the reviewed literature shows a trend to support normative weightings and non-compensatory aggregation approaches”

And in my opinion, this is the right approach

6- In page 2 “Sinisterra-Solís et al. (2023) estimated a pool of indicators related to the environmental and social dimensions (e.g. damage to natural ecosystem and to human health) for a group of Spanish farms”

And where is the economics?

7- What is NUTS? You do not define it

8- Fig 1 introduces AHP, and that is a descriptive and compensation method, that you discarded using before

9- “considering that no cut-off points are established in most of the sustainability attributes, such as setting limits to the capacity to assimilate natural environmental impacts”

I disagree. If we do not put a cutoff, like the maximum contamination of say SOx, in the atmosphere, how can we judge different alternatives regarding this environmental issue?

This is equivalent to consider that every contamination value is OK. For instance, if we do not put a limit to maximum daily consumption of water per household in a construcción development of 50 houses, how can we determine the volume of water to be supplied to the whole undertaking?

At the same time, we need to put a lower limit of water supply, as fixed by the WHO (Words Health Organization)

10- In page 4 you rightly refer to the damage to the environment. In addition, you take into account something that not many researches consider, and it is the externalities either in the environment and in the economy and perhaps in human health. Needless to say, I am in complete agreement with your approach

11- In Section 2.2.5 the AHP is selected. Now, if you have been claiming that the study must follow normativity, how now you use this method that is essentially descriptive and with compensation. In addition, remember that subjective weights only provide invented values for relative importance of criteria, and do not participate in the evaluation of alternatives, because they work with criteria , not with performance values and detecting their attributes in each criterion, as objective weights do.

AHP is the most used MCDM, true, but normative? Is it normative to make judgements based on intuitions?

12- In page 14” It is based on a composite indicator constructed from quantitative attributes selected from a top-down approach, assigning weights normatively to the attributes and considering a partial trade-off in their aggregation”

I am lost with this paragraph.

a) How can you select criteria by using the top-down approach? With this approach you are altering initial data by multiplying each criterion by a weight, which value does not have any mathematical foundation.

b) Why quantitative criteria, don’t you consider subjective criteria, as for instance people’s opinions?

c) I would like to know how you can assign normatively weights to criteria, unless, of course, that you use objective weights

d) Aggregation using trade-offs?

13- “Based on the reviewed literature, some of these assumptions can be questionable and seen as a weakness of the approach”

Well, at least you recognize that some of these has been questionable and that I am not the only one in challenging these assumptions.

I hope that these comments can help you

Nolberto Munier