“…In summary, based on the literature reviewed, we can group the empirical studies together by two fundamental characteristics: on the one hand, those papers that do not consider an asset valuation model to measure the relationship between investor sentiment and market returns of assets [12,17,28,37,79,80], versus those who do [7,9,11,62,64,66,67,81,82]; and on the other, studies that develop their own sentiment indexes [11,35,41,71,82] versus those using indexes developed by specialized investors or economic agents [9,36,64,[82][83][84].…”