Designing better algorithms: 5 case studies

In this article, using a few examples and solutions, I show that the "best" algorithm is many times not what data scientists or management think it is. As a result, too many times, misfit algorithms are implemented. Not that they are bad or simplistic. To the contrary, they are usually too complicated, but the biggest drawback is that they do not address the key problems. Sometimes they lack robustness, sometimes they are not properly maintained (for instance they rely on outdated lookup tables), sometimes they are unstable (they rely on a multi-million rule system), sometimes the data is not properly filtered or inaccurate, and sometimes they are based on poor metrics that are easy to manipulate by a third party seeking some advantage (for instance, click counts are easy to fake.)