Empirical and theoretical investigations of chaotic phenomena in macroeconomic systems are presented. Basic issues and techniques in testing economic aggregate movements are discussed. Evidence of low dimensional strange attractors is found in several empirical monetary aggregates. A continuous time deterministic model with delayed feedback is proposed to describe the monetary growth. Phase tra...

Machine learning systems are vulnerable to adversarial attack. By applying the input object a small, carefully-designed perturbation, classifier can be tricked into making an incorrect prediction. This phenomenon has drawn wide interest, with many attempts made explain it. However, complete understanding is yet emerge. In this paper we adopt slightly different perspective, still relevant classi...