Is there any connection between the network morphology and the fluctuations of the stock market index?

•Behavioral model to study market index fluctuations in several scenarios.•Investigation of different trust network morphologies on the index oscillations.•Remarkable effects due to complex network synchronization in anti-imitator scenario.•Fluctuations of the stock market index are heavily biased by the network morphology.•Mixing scenario enhances self-affine features of the stock market index.

Models which consider behavioral aspects of the investors have attracted increasing interest in the Finance and Econophysics literature in the last years. Different behavioral profiles (imitation, anti-imitation, indifference) were proposed for the investors, which take their decision based on their trust network (neighborhood). Results from agent-based models have shown that most of the features observed in actual stock market indices can be replicated in simulations. Here, we present a deeper investigation of an agent based model considering different network morphologies (regular, random, small-world) for the investors’ trust network, in an attempt to answer the question raised in the title. We study the model by considering four scenarios for the investors and different initial conditions to analyze their influence in the stock market fluctuations. We have characterized the stationary limit for each scenario tested, focusing on the changes introduced when complex networks were used, and calculated the Hurst exponent in some cases. Simulations showed interesting results suggesting that the fluctuations of the stock market index are strongly affected by the network morphology, a remarkable result which we believe was never reported or predicted before.