This ebook offers you a practical and statistically based methodology to evaluate the compatibility of a couple, minimizing subjectivity in the choice. You will learn to identify 5 fundamental criteria that influence the success of a relationship, avoiding future problems and possible painful separations. Unlike traditional views that oscillate between eternal idealism and pessimism, this book provides you with concrete tools to analyze whether your relationship is based on solid foundations or on quicksand. The methodology, designed to be accessible and consider both logic and emotions, will allow you to perform continuous evaluations over time, adapting to individual changes and strengthening the union. With overlapping calculation graphs, an innovative technique, you can perform quick and precise evaluations. Discover how these 5 basic criteria, key to the beginning of a relationship, can make the difference between a happy and lasting union, and an experience full of conflicts and disappointments.