PT - JOURNAL ARTICLE AU - Mohanty, Malaya AU - Ranjan Samal, Satya AU - Samal, Kundan TI - Developing a Speed-Based Congestion Severity Index Using the Clustering Technique for Developing Countries DP - 2025 Apr 1 TA - Communications - Scientific Letters of the University of Zilina PG - D67--D75 VI - 27 IP - 2 AID - 10.26552/com.C.2025.020 IS - 13354205 AB - A novel approach for traffic congestion assessment has been presented using percentile speeds as key indicators, focusing on urban roads. By evaluating the 98th, 85th, and 15th percentile speeds, authors of the research developed a congestion severity index, offering a more precise and intuitive method for analyzing traffic flow compared to traditional travel time-based indices. Key congestion indices, such as the Planning Time Index (PTI) and Travel Time Index (TTI) were compared to percentile speeds, revealing a significant association with the 15th and 85th percentile speeds. The K-means clustering technique was applied to classify congestion severity into three levels, validated by a high silhouette value indicating the robust clustering. The study's speed-based congestion severity index provides a practical and efficient framework for real-time congestion management, particularly in heterogeneous traffic environments.