Chapter 1: Fuzziness in Information Extracted from Tweets' Hashtag and Keywords.- Chapter 2: Why Triangular and Trapezoid Membership Functions: A Simple Explanation.- Chapter 3: Probabilistic and More General Uncertainty-Based (e.g., Fuzzy) Approaches to Crisp Clustering Explain the Empirical Success of the K-Sets Algorithm.- Chapter 4: Statistical Approach to Fuzzy Cognitive Maps.- Chapter 5: Semi-Supervised Learning to Rank with Nonlinear Preference...