ESG Investing and Investor Behavioural Biases: A Systematic Review and Integrated Behavioural Finance Framework: A Systematic Literature Review

Abstract

This paper presents systematic literature review (SLR) based on the PRISMA framework on the nexus of ESG and investor behavioural biases in the stock market. The selection of 72 studies that fulfilled all the eligibility criteria was drawn from an initial sample of 5213 from Scopus, Web of Science, and additional databases, and synthesised thematically. It considers the interplay between cognitive and emotional biases (such as herding, overconfidence, disposition effect, loss aversion, confirmation bias, anchoring) and the quality of the ESG disclosure, rating divergence, and the perception of greenwashing to influence investment behaviour. The results show that investor psychology and financial expertise, as well as market conditions, play a significant role in determining the impact of ESG factors, which do not seem to work on a strictly rational and informational basis. On this synthesis, the paper lays out a new Integrated Behavioural Finance Framework, where the quality of the signals is proposed as an antecedent of the heuristic process and a set of testable propositions for future empirical research. The review reveals several limitations, including geographic underrepresentation (especially the GCC), biases of anchoring and regret aversion, and the lack of experimental and debiasing intervention studies. Implications are provided for investors, financial advisors, regulators and researchers interested in modelling sustainable investment decision making in a behaviourally realistic way. Findings: The review indicates that the impact of ESG on stock market investment decisions is mediated by behaviour and not just information. Investor behaviour is influenced by the interplay between the quality of ESG disclosure and rating divergence, as well as perceptions of greenwashing and the disposition effect, and overconfidence and herding. Institutional investors seem to distinguish between ESG dimensions based on the materiality of the sector and are generally less prone than retail investors to be biased in their processing of ESG information, who are more liable to herding and greenwashing risk. Higher divergence due to rating, coupled with higher voluntary disclosure, paradoxically increases (not resolves) the divergence, irrespective of the performance of the firms. Originality and Value: The novelty of this paper is that it combines in a systematic way two streams of literature in a PRISMA-based synthesis, instead of tackling the investor psychology and the quality of the ESG disclosure separately. It presents an Integrated Behavioural Finance Framework where signal quality is an antecedent to heuristic processing, that is moderated by investor-level and market-level variables, and testable propositions for future empirical testing. The review contributes to the field by pointing to Islamic finance's values-based screening logic, indicating that the GCC is a hugely under-researched context, and revealing gaps in methods and studies that have informed future research, including a lack of experimental debiasing studies.