This paper analyzes the impact of disagreement on equilibrium stock returns in a multi-asset market. Most dynamic models of disagreement focus on a market with a single stock which is a claim on the aggregate consumption. In reality, investors can speculate on the future cashflows of multiple stocks. In a continuous-time pure exchange economy, we assume investors have logarithmic preferences and disagree about future dividends. We show that the effect of disagreement can be very different in a multi-asset market compare to a single-asset market. In a single-asset market, although disagreement affects equilibrium returns, the effect is negligible if the dispersion in beliefs is small. In comparison, when there are multiple assets in the market, investors may have small disagreement about each asset, however, when the number of assets is relatively large (as in the real financial market), the overall level of belief dispersion could be much higher compared to the single-asset market. Consequently, we find that effect of disagreement can lead to a much higher excess volatility and larger time-variation in expected returns in a multi-asset market than in a single-asset market. We also study the effect of correlation in optimism/pessimism between assets. We find that correlation in optimism/pessimsm can lead to excess correlation in asset returns even though assets have independent future dividends. Furthermore, we show that when optimism/pessimism are negatively correlated, assets with the same level of belief dispersion can have different excess volatilities and also different expected returns. Lastly, we find that in a multi-asset market, initial run-up in asset prices may not lead any fluctuations in the distribution of consumption shares, thus have no effect of expected asset returns, which is in contrast of Yan (2010)’s finding of price-overshooting and mean-reversion in asset returns.
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