Abstract

This paper empirically examines the financial performance of a UK unit trust that was initially “conventional” and later adopted socially responsible investment (SRI) principles (ethical investment principles). Comparison is made with three similar conventional funds whose investment objectives remained unchanged. Analysis techniques employed in previous studies find similar results: mean risk-adjusted performance is unchanged by the switch to SRI, with no evidence of over-or under-performance relative to the benchmark market index by any of the four funds. More interestingly, changes in variability of returns over time are also modelled using generalised autoregressive conditional heteroscedasticity models, not previously applied to SRI funds so far as is known. Results show a temporary increase in variability of returns, followed by a return to previous levels after around 4 years. Evidence shows the increased variability to be associated with the adoption of SRI rather than with a change in fund management. Possible explanations for the subsequent reduction in variability include the spread of corporate social responsibility activities by firms and learning by fund managers. In addition to reporting on a previously unobserved phenomenon, this paper raises questions for further research.