Heat waves or Meteor showers: Empirical evidence from the stock markets

In order to study the volatility spillovers / the transfer of volatilities from spot and futures markets for the period 1st January 2001 to 30th November 2005 with high frequency data i.e., one minute intervals, we have used GARCH models to compute volatilities and VAR models for the returns of different markets and for the volatilities. It is evident that, these VAR models for the volatilities can exhibit the nature of the change in volatility. In a heat wave, the conditional variance of the returns in spot (futures) market depends only upon the past shocks in the given market. For meteor showers, the impact of shocks on spot (futures) markets are transferred from other i.e., futures (spot) markets. With the VAR (1)-GARCH (1,1) analysis, we found that both series are I(1) and that a bi-directional relationship exists between the spot and future market return series. Empirically it is evident that both heat waves and meteor showers exist in Indian spot and futures markets.Volatility Spillovers, Heat Waves, Meteor Showers, Indian Stock Market.

A Comparative Analysis of Portfolio Optimization Using Mean-Variance, Hierarchical Risk Parity, and Reinforcement Learning Approaches on the Indian Stock Market

This paper presents a comparative analysis of the performances of three portfolio optimization approaches. Three approaches of portfolio optimization that are considered in this work are the mean-variance portfolio (MVP), hierarchical risk parity (HRP) portfolio, and reinforcement learning-based portfolio. The portfolios are trained and tested over several stock data and their performances are compared on their annual returns, annual risks, and Sharpe ratios. In the reinforcement learning-based portfolio design approach, the deep Q learning technique has been utilized. Due to the large number of possible states, the construction of the Q-table is done using a deep neural network. The historical prices of the 50 premier stocks from the Indian stock market, known as the NIFTY50 stocks, and several stocks from 10 important sectors of the Indian stock market are used to create the environment for training the agent.Comment: The report is 52 pages long. It is based on the capstone project done in the post graduate course of data science in Praxis Business School, Kolkata, India, of the Autumn Batch, 202

A Comparative Study of Portfolio Optimization Methods for the Indian Stock Market

This chapter presents a comparative study of the three portfolio optimization methods, MVP, HRP, and HERC, on the Indian stock market, particularly focusing on the stocks chosen from 15 sectors listed on the National Stock Exchange of India. The top stocks of each cluster are identified based on their free-float market capitalization from the report of the NSE published on July 1, 2022 (NSE Website). For each sector, three portfolios are designed on stock prices from July 1, 2019, to June 30, 2022, following three portfolio optimization approaches. The portfolios are tested over the period from July 1, 2022, to June 30, 2023. For the evaluation of the performances of the portfolios, three metrics are used. These three metrics are cumulative returns, annual volatilities, and Sharpe ratios. For each sector, the portfolios that yield the highest cumulative return, the lowest volatility, and the maximum Sharpe Ratio over the training and the test periods are identified.Comment: This is the draft version of the chapter that has been accepted for publication in the edited volume titled "Data Science: Theory and Practice". The volume is edited by Jaydip Sen and Sayantani Roy Choudury and will be published by IntechOpen, London, UK. The chapter is 74 pages long and it contains 32 tables and 62 figure

Portfolio Optimization: A Comparative Study

Portfolio optimization has been an area that has attracted considerable attention from the financial research community. Designing a profitable portfolio is a challenging task involving precise forecasting of future stock returns and risks. This chapter presents a comparative study of three portfolio design approaches, the mean-variance portfolio (MVP), hierarchical risk parity (HRP)-based portfolio, and autoencoder-based portfolio. These three approaches to portfolio design are applied to the historical prices of stocks chosen from ten thematic sectors listed on the National Stock Exchange (NSE) of India. The portfolios are designed using the stock price data from January 1, 2018, to December 31, 2021, and their performances are tested on the out-of-sample data from January 1, 2022, to December 31, 2022. Extensive results are analyzed on the performance of the portfolios. It is observed that the performance of the MVP portfolio is the best on the out-of-sample data for the risk-adjusted returns. However, the autoencoder portfolios outperformed their counterparts on annual returns.Comment: This is the preprint of the book chapter accepted for publication in the book titled "Deep Learning - Recent Finding and Researches" edited by Manuel Dom\'inguez-Morales. The book is scheduled to be be published by IntechOpen, London, UK in January 2024. This is not the final version of the chapte

Relation between Financial Market Structure and the Real Economy: Comparison between Clustering Methods

We quantify the amount of information filtered by different hierarchical clustering methods on correlations between stock returns comparing it with the underlying industrial activity structure. Specifically, we apply, for the first time to financial data, a novel hierarchical clustering approach, the Directed Bubble Hierarchical Tree and we compare it with other methods including the Linkage and k-medoids. In particular, by taking the industrial sector classification of stocks as a benchmark partition, we evaluate how the different methods retrieve this classification. The results show that the Directed Bubble Hierarchical Tree can outperform other methods, being able to retrieve more information with fewer clusters. Moreover, we show that the economic information is hidden at different levels of the hierarchical structures depending on the clustering method. The dynamical analysis on a rolling window also reveals that the different methods show different degrees of sensitivity to events affecting financial markets, like crises. These results can be of interest for all the applications of clustering methods to portfolio optimization and risk hedging.Comment: 31 pages, 17 figure