Definition of q-rung orthopair fuzzy set :

Understand the definition of q-rung orthopair fuzzy set and the operations of q-rung orthopair fuzzy set. We discuss the q-rung parameter and provide a q-rung orthopair fuzzy set with example for flexible data representation.

q-Rung Orthopair Fuzzy Set (q-ROFS)

Introduction

The q-Rung Orthopair Fuzzy Set (q-ROFS), introduced by Yager (2017), is a powerful tool for handling high levels of uncertainty. As the value of the rung q increases, the space of acceptable membership grades expands. This means that if a piece of information cannot be expressed as an Intuitionistic or Pythagorean fuzzy set, it can almost always be expressed as a q-ROFS by simply increasing q.

Definition of q-ROFS

A q-Rung Orthopair Fuzzy Set A in a universe X is defined as:

A = { ⟨ x, μA(x), νA(x) ⟩ | x ∈ X }

Subject to the fundamental constraint:

0 ≤ (μA(x))q + (νA(x))q ≤ 1

Where q ≥ 1. The hesitancy degree is defined as:

πA(x) = ( 1 – (μAq + νAq) )1/q

Algebraic Operational Laws

Let α₁ = (μ₁, ν₁) and α₂ = (μ₂, ν₂) be two q-ROFNs. For any scalar λ > 0, the operations are:

1. Addition (⊕)
α₁ ⊕ α₂ = ( (μ₁q + μ₂q – μ₁qμ₂q)1/q , ν₁ν₂ )
2. Multiplication (⊗)
α₁ ⊗ α₂ = ( μ₁μ₂ , (ν₁q + ν₂q – ν₁qν₂q)1/q )
3. Scalar Multiplication (λ.α)
λ.α = ( (1 – (1 – μq)λ)1/q , νλ )
4. Power (αλ)
αλ = ( μλ , (1 – (1 – νq)λ)1/q )
5. Complement (αc)
αc = ( ν , μ )
Step-by-Step Example (q = 3):

Let α₁ = (0.7, 0.4) and α₂ = (0.5, 0.6).
Check Constraint: 0.7³ + 0.4³ = 0.343 + 0.064 = 0.407 (≤ 1)

Addition (α₁ ⊕ α₂):
• μres = (0.7³ + 0.5³ – 0.7³ × 0.5³)1/3
• μres = (0.343 + 0.125 – 0.0428)1/3 = (0.4252)1/30.752
• νres = 0.4 × 0.6 = 0.24
Result: (0.752, 0.24)

Multiplication (α₁ ⊗ α₂):
• μres = 0.7 × 0.5 = 0.35
• νres = (0.4³ + 0.6³ – 0.4³ × 0.6³)1/3
• νres = (0.064 + 0.216 – 0.0138)1/3 = (0.2662)1/30.643
Result: (0.35, 0.643)
Math Tools

Designed by: Dr. M.U. Mirza

Mathematical Researcher & Educator

Machine Learning Fuzzy Sets Computational Math Graph Theory
I am a researcher and mathematician dedicated to the study and application of advanced mathematical models. I offer research guidance and personalized video lectures for students and professionals seeking deep insights into mathematics and computational sciences.
📢 Academic Update: Currently seeking University Faculty positions or Post-Doc research opportunities worldwide.
Get Math Tutoring & Guidance
Scroll to Top