Extension card · Neutrosophic
Neutrosophic TODIM (Ji, Zhang & Wang, 2018)
N-TODIM is the form of TODIM used when the values in the decision table are not single numbers but an independent (neutrosophic) triple of truth, indeterminacy and falsity degrees. It runs the same loss-aversion logic through a distance between these triples and a score-function comparison.
Base method
TODIM →
Philosophy, mechanics, strengths and weaknesses are on the base method card; this card describes only the difference.
Data type (family)
Neutrosophic →
What this data type is, when to use it, how to write it in a cell: the family's full account is here.
What Changes from the Base Method?
Four things change; the reference-criterion mechanism and the magnification of the loss side by θ do not.
Cells. In crisp TODIM every cell is a single number. Here every cell consists of three independent degrees: truth (T), indeterminacy (I) and falsity (F). All three lie between 0 and 1 and their sum is not forced to equal 1; unlike the intuitionistic fuzzy pair, indeterminacy comes from its own source rather than being what remains of the other two. Weights are crisp numbers. DecisionMind does not support group decisions at this extension; every cell belongs to a single evaluation.
Scale equalisation. In crisp TODIM, cost criteria are converted to the benefit direction by scaling within the column. Here the same aim is achieved with a neutrosophic complement: every (T, I, F) triple in a cost criterion is replaced with (F, 1−I, T). That is, truth and falsity swap places, and indeterminacy turns into its own complement. This is a reversal of direction, not a division.
Distance and score. In crisp TODIM, the difference between two values is a direct subtraction. Here the process splits into two steps. First, the distance between two triples is computed from the differences of their truth, indeterminacy and falsity components; this distance is symmetric and does not say which alternative comes out ahead. The winning-losing direction is determined by a score function: a triple with high truth and low indeterminacy and falsity receives a higher score. In crisp TODIM the difference gives both the magnitude and the direction in one step. Here the magnitude comes from the distance and the direction from the score comparison, just as in the intuitionistic fuzzy extension, except that here all three components (T, I, F) enter the calculation independently.
Result. The global value is again a single number normalised between 0 and 1; the indeterminacy in the triple enters the distance and score calculations but the result settles into a crisp number, it does not stay neutrosophic.
DecisionMind holds fixed, in this extension, the closed-form score function that subtracts falsity and twice the indeterminacy from truth and then halves the result; θ defaults to 1 and can be changed by the user.
How to Read the Output
The global value is read as in crisp TODIM: the lowest total dominance is scaled to 0 and the highest to 1; it is not an absolute measure of "good" or "bad".
The difference is this. The score function penalises indeterminacy directly: of two triples with the same truth and falsity, the one with higher indeterminacy receives a lower score. So if an alternative's global value is low, whether this comes from weak evidence, that is, low truth and high falsity, or from missing information, that is, high indeterminacy, must be read separately. The two push the global value in the same direction, but they come from different sources, and the report must not conflate them.
Thus instead of writing:
"According to N-TODIM, A3 is the best alternative"
the report should read:
"The degrees of truth, indeterminacy and falsity have been compared with the neutrosophic distance, and the gain-loss direction has been determined by the score function; A3 has the highest global value, and this ranking holds between θ=0.5 and θ=5"
When to Prefer This over the Base Method
This extension is appropriate when information about a criterion is missing, inconsistent or contradictory, and this matters for the decision itself. It is equally appropriate when the intuition that the decision maker is more sensitive to losses than to gains fits the nature of the decision.
If the evaluation rests on a reliable measurement, or an expert does not express a separate indeterminacy share, crisp TODIM should be kept; opening data into a neutrosophic triple merely to look more thorough adds no information. If criteria are measured, or the table is mixed, DecisionMind requires a single data type; a measured criterion is written as the triple (t, 0, 1−t). This embedding says "no indeterminacy" and is honest, but it adds no information. TODIM's exit condition applies in exactly the same way: if no compromise is acceptable on one criterion, elimination should be applied first; if the loss-aversion assumption does not fit, a symmetric, fully compensatory method such as neutrosophic TOPSIS should be preferred instead.
Mistakes Specific to This Extension
Forcing the sum of the three components to equal 1. Truth, indeterminacy and falsity are independent; their sum exceeding 1 is natural. Forcing the sum to 1 reduces the neutrosophic structure to an intuitionistic fuzzy pair and erases the contribution of the third component, namely indeterminacy coming from its own source.
Deriving indeterminacy from truth and falsity. If indeterminacy is computed as "1 − T − F," it carries no independent information; indeterminacy must come from its own source (a missing record, a contradictory report, a small sample).
Applying the cost-criterion complement incorrectly. When truth and falsity swap places, indeterminacy must also turn into its own complement (1−I); changing only T and F and leaving I as it is applies the direction reversal incompletely and distorts the ranking.
Choosing θ too small. As θ shrinks, the loss side grows disproportionately; where a small difference turns into an excessive difference in the global value, the choice of θ must be justified in the report.
The governing principle is this:
In N-TODIM, indeterminacy is a component independent of truth and falsity and is separately penalised in the score function; whether a fall in the global value comes from weak evidence or from missing information must be disentangled in the report.
Cases
The first case is DecisionMind's validation example: a three-alternative, three-criterion, hand-traceable neutrosophic table, built synthetically to be faithful to the formulas rather than taken from an article or book page. The second case is an illustrative fiction.
1. Illustrative example: Neutrosophic scoring of three projects on three criteria
Three projects are evaluated on three criteria; every cell consists of a truth (T), indeterminacy (I) and falsity (F) degree, all three "higher is better". Weights are crisp; the first criterion carries the highest weight and is the reference criterion.
| Project | Criterion 1 | Criterion 2 | Criterion 3 |
|---|---|---|---|
| A1 | (T 0.70; I 0.20; F 0.10) | (T 0.60; I 0.30; F 0.20) | (T 0.50; I 0.40; F 0.30) |
| A2 | (T 0.50; I 0.30; F 0.40) | (T 0.70; I 0.20; F 0.20) | (T 0.60; I 0.30; F 0.30) |
| A3 | (T 0.80; I 0.10; F 0.20) | (T 0.50; I 0.40; F 0.30) | (T 0.70; I 0.30; F 0.20) |
| Direction | higher is better | higher is better | higher is better |
| Weight | 0.40 (reference) | 0.30 | 0.30 |
The method computes each cell's score (subtracting falsity and twice the indeterminacy from truth), establishes which project has the higher score on each criterion, computes the neutrosophic distance, sums a positive contribution on the winning side and a negative contribution magnified by θ=1 on the losing side, and scales the global value to the 0-1 range.
| Project | Global value | Rank |
|---|---|---|
| A3 | 1.000 | 1 |
| A2 | 0.213 | 2 |
| A1 | 0.000 | 3 |
The result reads as follows. A3 has the highest truth and the lowest indeterminacy on the first criterion (the reference, and the heaviest); this advantage more than offsets its weaker profile on the other criteria. A1 is third because it has the lowest score on the first criterion; its global value of 0 does not mean an absolute "worthlessness", only the lowest relative dominance among these three projects. A2 sits in between, second, with a balanced profile that does not stand out on any single criterion.
The committee's hesitation is this: if A2's indeterminacy on the first criterion (I=0.30) is reduced by gathering more data and its truth rises, that is, if T moves from 0.50 to 0.60, I from 0.30 to 0.25, and F from 0.40 to 0.30, how does its global value change? Recomputed independently in Python, A2's value rises from 0.213 to 0.498 but still does not overtake A3. Conversely, if indeterminacy in the same cell instead rises, from I=0.30 to I=0.50, A2's value falls to 0.033. The ranking stays A3-A2-A1 in both cases, but A2's distance relative to A3 is highly sensitive to the size of the indeterminacy in this one cell. If the weights on C1 and C3 were swapped, A2's value would fall to 0.074, and the ranking would again stay unchanged.
In the report: "With the highest weight given to the first criterion, A3 is clearly ahead; whether A2's indeterminacy on the same criterion is reduced or increased, the order A3-A2-A1 is preserved, though A2's distance relative to A3 is highly sensitive to the size of the unknown share on this criterion."
Source: This case is DecisionMind's validation example for the N-TODIM engine; the matrix and weights were produced, as a small hand-computable example, to be faithful to the formulas, and are not the table from Ji, Zhang and Wang's (2018) article. That article addresses a multi-valued neutrosophic environment; the single-valued special case is used here, as an illustrative example. The figures for the indeterminacy-sensitivity and weight-swap scenarios were independently recomputed with the same algorithm by this card's author.
2. Retail: An e-commerce company's decision to enter a new market
An e-commerce company will decide which of three new country markets to enter first. Criteria: local demand growth potential, favourability of the competitive environment and adequacy of logistics infrastructure; all three "higher is better". The company has no past sales data in these markets. A judgement is formed for each criterion, for instance "this market is favourable in terms of demand growth". The marketing team derives truth from favourable evidence, namely industry reports and experience in similar markets; falsity from adverse evidence, namely local competitor analyses; and indeterminacy from missing data, namely the fact that no field research has yet been carried out in that country. The company gives the highest weight (the reference criterion) to demand growth potential.
The method compares the three markets pairwise: it determines the winning-losing direction from the score difference, computes the neutrosophic distance and computes the global value. Suppose the market with the highest truth on demand growth potential also has the highest indeterminacy on logistics infrastructure (owing to the lack of field research), and still comes first on global value, because the demand criterion is the reference criterion.
The company's hesitation is this: the high indeterminacy on the logistics infrastructure criterion does not distinguish between a genuine weakness and a mere lack of data; the global value penalises both in the same direction. The company should not finalise its investment decision before completing its field research, and the report should state separately that the source of this indeterminacy is a lack of data.
In the report: "With the highest weight given to demand growth potential, the first market clearly stands out; however, the high indeterminacy this market carries on the logistics infrastructure criterion stems from a lack of field research, and the final decision should not be finalised before this is confirmed with field data."
3. What Not to Do
Instead of turning a measured sales ratio (for instance, last year's realised growth) directly into a triple and writing "no indeterminacy" as (T, 0, 1−T), adding an indeterminacy share by feel is wrong: this produces an estimate in which no component rests on a source of evidence. The second error is forcing the sum of the three components to equal 1, or computing indeterminacy as "1 − T − F"; this breaks the independence principle of the neutrosophic structure and reduces it to carrying the same information as an intuitionistic fuzzy pair. The third error is reading A3's global value of 1.000 as "a perfect project"; this value only scales these three projects relative to one another, it does not express absolute perfection.
Sources
For the formulas behind each step, the intermediate tables and citation formats, see the DecisionMind method page: decisionmind.app/library/n-todim
Ji, P., Zhang, H.-Y., & Wang, J.-Q. (2018). A projection-based TODIM method under multi-valued neutrosophic environments and its application in personnel selection. Neural Computing and Applications, 29(1), 221–234. DOI: 10.1007/s00521-016-2436-z
Gomes, L. F. A. M., & Lima, M. M. P. P. (1992). TODIM: Basics and application to multicriteria ranking of projects with environmental impacts. Foundations of Computing and Decision Sciences, 16, 113–127. (no DOI)
Smarandache, F. (1998). Neutrosophy: Neutrosophic Probability, Set, and Logic. American Research Press, Rehoboth. (no DOI)
Ye, J. (2014). A multicriteria decision-making method using aggregation operators for simplified neutrosophic sets. Journal of Intelligent & Fuzzy Systems, 26(5), 2459–2466. DOI: 10.3233/IFS-130916