A New Similarity Measure of q-Rung Orthopair Fuzzy Sets based on the Jaccard Index with its Application to the Orthopairian TOPSIS Method
Published 2026-09-19
Keywords
- Similarity Measure,
- Jaccard Index,
- q-Rung Orthopair Fuzzy Sets,
- Multi-Criteria Decision-Making,
- Technique for Order of Preference by Similarity to Ideal Solution
- Orthopairian TOPSIS ...More
Copyright (c) 2026 Zahid Hussain, Kashif Ali, Mehboob Ali (Author)

This work is licensed under a Creative Commons Attribution 4.0 International License.
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Abstract
This paper introduces a novel similarity measure for q-rung orthopair fuzzy sets (q-ROFSs) based on the Jaccard index, aimed at improving decision-making processes under uncertainty. The q-ROFSs are flexible generalizations of intuitionistic fuzzy sets and Pythagorean fuzzy sets, offering improved flexibility in representing uncertainty. Hence, we proposed a novel SM using the Jaccard index for q-ROFSs. The suggested similarity measure considers both the membership and non-membership degrees of q-ROFSs and adheres to key properties such as boundedness, commutativity, and sensitivity. Numerical examples validate the measure, showing it to be both reasonable and effective. The proposed similarity measure is further integrated with the technique for order of preference by similarity to ideal solution (TOPSIS) method, forming orthopairian TOPSIS (OTOPSIS), which enables more accurate ranking of alternatives in uncertain environments. A practical example demonstrates the method's effectiveness, emphasizing its potential for multi-criteria decision-making applications in complex scenarios. The results confirm that the proposed measure is well-suited for decision-making in uncertain, multi-attribute settings.
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References
- Zadeh, L. A. (1965). Fuzzy sets. Information and Control, 8(3), 338–353. https://doi.org/10.1016/S0019-9958(65)90241-X.
- Pal, S. K., & Dutta Majumder, D. K. (1986). Fuzzy mathematical approach to pattern recognition. Halsted Press.
- Bojadziev, G., & Bojadziev, M. (2007). Fuzzy logic for business, finance, and management (2nd ed.). World Scientific.
- Yang, M.-S., Hussain, Z., & Ali, M. (2020). Belief and plausibility measures on intuitionistic fuzzy sets with construction of belief-plausibility TOPSIS. Complexity, 2020, Article 7849686. https://doi.org/10.1155/2020/7849686.
- Saif-Ud-Din, A., Hussain, S., Hussain, J., Luqman, M., Hussain, J., & Ali, S. (2022). Evaluation of heavy metal contamination in indigenous fruits and associated human health risk: Evidence from Fuzzy-TOPSIS approach. Global NEST Journal, 24(3), 435–444. https://doi.org/10.30955/gnj.004236.
- Sanayei, A., Mousavi, S. F., & Yazdankhah, A. (2010). Group decision making process for supplier selection with VIKOR under fuzzy environment. Expert Systems with Applications, 37(1), 24–30. https://doi.org/10.1016/j.eswa.2009.04.063.
- Atanassov, K. T. (1999). Intuitionistic fuzzy sets: Theory and applications. Physica-Verlag. https://doi.org/10.1007/978-3-7908-1870-3.
- Chaira, T., & Ray, A. K. (2017). Fuzzy image processing and applications with MATLAB. CRC Press.
- Biswas, S. K., De, R., & Roy, A. R. (2001). An application of intuitionistic fuzzy sets in medical diagnosis. Fuzzy Sets and Systems, 117(2), 209–213. https://doi.org/10.1016/S0165-0114(98)00235-8.
- Abbas, S., Hussain, Z., Hussain, S., Sharif, R., & Hussain, S. (2021). Intuitionistic fuzzy entropy and its applications to multicriteria decision making with IF-TODIM. Journal of Mechanics of Continua and Mathematical Sciences, 16(7), 99–119. https://doi.org/10.26782/jmcms.2021.07.00009.
- Yager, R. R. (2014). Pythagorean membership grades in multicriteria decision making. IEEE Transactions on Fuzzy Systems, 22(4), 958–965. https://doi.org/10.1109/TFUZZ.2013.2278989.
- Yager, R. R. (2013). Pythagorean fuzzy subsets. In 2013 Joint IFSA World Congress and NAFIPS Annual Meeting (IFSA/NAFIPS) (pp. 57–61). IEEE. https://doi.org/10.1109/IFSA-NAFIPS.2013.6608375.
- Yager, R. R., & Alajlan, N. (2017). Approximate reasoning with generalized orthopair fuzzy sets. Information Fusion, 38, 65–73. https://doi.org/10.1016/j.inffus.2017.02.005.
- Teodorovic, D. (1999). Fuzzy logic systems for transportation engineering: The state of the art. Transportation Research Part A: Policy and Practice, 33(5), 337–364. https://doi.org/10.1016/S0965-8564(98)00024-X.
- Hussain, Z., & Yang, M.-S. (2018). Entropy for hesitant fuzzy sets based on Hausdorff metric with construction of hesitant fuzzy TOPSIS. International Journal of Fuzzy Systems, 20(8), 2517–2533. https://doi.org/10.1007/s40815-018-0523-2.
- Hwang, C.-M., Yang, M.-S., & Hung, W.-L. (2018). New similarity measures of intuitionistic fuzzy sets based on the Jaccard index with its application to clustering. International Journal of Intelligent Systems, 33(8), 1672–1688. https://doi.org/10.1002/int.21990.
- Yang, M.-S., & Hussain, Z. (2018). Fuzzy entropy for Pythagorean fuzzy sets with application to multicriterion decision making. Complexity, 2018, Article 2832839. https://doi.org/10.1155/2018/2832839.
- Hussain, Z., Abbas, S., Hussain, S., Ali, Z., & Jabeen, G. (2021). Similarity measures of Pythagorean fuzzy sets with applications to pattern recognition and multicriteria decision making with Pythagorean TOPSIS. Journal of Mechanics of Continua and Mathematical Sciences, 16(6), 64–86. https://doi.org/10.26782/jmcms.2021.06.00006.
- Karamat, T., & Sarfraz, M. (2026). A Pythagorean Fuzzy Multiple-Attribute Decision-Making Model for Smart Governance Research Applications. Applied Research Advances, 2(1), 146-161. https://doi.org/10.65069/ara2120266.
- Zadeh, L. A., Klir, G. J., & Yuan, B. (1996). Fuzzy sets, fuzzy logic, and fuzzy systems: Selected papers. World Scientific. https://doi.org/10.1142/2895.
- Peng, X., & Liu, L. (2019). Information measures for q-rung orthopair fuzzy sets. International Journal of Intelligent Systems, 34(8), 1795–1834. https://doi.org/10.1002/int.22115.
