My experience at the Summer School in Economics and Finance (SSEF) 2021 was one of the most challenging of my entire academic life. In particular, I would like to share my experience in the Heterogeneous Agents for Asset Pricing and Macroeconomics course.
This course was exciting to learn because we usually study the behavior of a representative agent (consumer, investor, and so on) in economic and financial models. Then we extrapolate this behavior at the aggregate level. However, the empirical evidence seems to support the relevance of heterogeneity in the agents, which would allow us to have a better degree of understanding of the rationality of their decisions.
In Macroeconomics, the representative agent assumption has been present throughout the traditional DSGE models. However, the models that consider the presence of heterogeneous agents have shown to be useful for the design of monetary policies (HANK Models) and fiscal policies that consider the unequal effects that these policies have on the real economy.
In Finance, agent heterogeneity plays a fundamental role in understanding asset allocation, given a price vector, considering the idiosyncratic characteristics of each agent such as age or income level that influence the choice of their portfolios. On the other hand, the literature has also considered the role of heterogeneity (preferences, background risks, frictions, etc.) in explaining aggregate asset prices (equity premium and risk-free rate).
During the course, we focus in particular on the standard incomplete markets model (SIM), which is the main workhorse to study heterogeneity. In this framework, we consider two heterogeneous agents in an environment of continuous and stochastic fluctuations of their income. To find each agent’s optimal consumption and portfolio, we used the famous Hamilton-Jacobi-Bellman (HJB) equation. To get this equation, it was essential to use stochastic calculus tools such as Ito’s Lemma, martingales, and Brownian motion types.
If you are interested in the next Summer School in Economics and Finance (coming in 2022), I would recommend you to have good previous training in optimization methods, differential equations, dynamic programming, and multivariate statistics, as well as good programming skills in software such as Matlab or R, would also be useful in most courses. Finally, having a lot of curiosity and passion for learning is fundamental to successfully passing this great summer challenge.
Christian
Leave a Reply