Yes / This paper investigates the role of institutional investor sentiment in the mean–variance relation. We find market returns are negatively (positively) related to market’s conditional volatility over bullish (bearish) periods. The evidence indicates institutional investors to be sentiment traders as well.

Yes / This paper investigates the mean-variance relation during different time periods within trading days. We reveal that there is a positive mean-variance relation when the stock market is closed (i.e., overnight), but the positive relation is distorted when the market is open (i.e., intraday). The evidence offers a new explanation for the weak risk-return tradeoff in stock markets.

Yes / Although a cornerstone of traditional finance theory, empirical evidence in support of a positive mean-variance relation is far from conclusive, with the behavior of retail investors commonly thought to be one of the root causes of departures from this expected relationship. The behavior of institutional investors, conventionally thought to be sophisticated and rational, has recently come under closer scrutiny, including in relation to investor sentiment. Drawing together these two strands of literature, this paper examines the impact of institutional investor sentiment on the mean-variance relation in six regions, including Asia (excl. Japan), Eastern Europe, Eurozone, Japan, Latin America, and the US, and across thirtyeight markets. Empirical evidence supports the differential impact of institutional investor sentiment on the mean-variance relation (i.e., positive or negative), both across regions and across markets. In particular, for markets with cultural proneness to overreaction and a low level of market integrity institutional investor sentiment tends to distort the risk-return tradeoff.