Depending on both your assumptions about the degree of information asymmetries and version of EMH, EMH can be seen as saying the retail investor and GS cannot beat the index so both should achieve the same investment outcomes. That would be one extreme.
I think the reality is that GS out competes the little guy on two factors: a) ability to actually do the research and make better assessments of the publicly known information (Give me the GS database and I will still not know what the GS analytical team knows, and definitely not in a useful time frame) and b) institutional factors that allows GS relevant but non-public information (e.g., order flow) and they also generate information that is relevant (new product type things).
Part of that is relevant to trading activities but part is going to impact long term, investment results.
Depending on both your assumptions about the degree of information asymmetries and version of EMH, EMH can be seen as saying the retail investor and GS cannot beat the index so both should achieve the same investment outcomes. That would be one extreme.
I think the reality is that GS out competes the little guy on two factors: a) ability to actually do the research and make better assessments of the publicly known information (Give me the GS database and I will still not know what the GS analytical team knows, and definitely not in a useful time frame) and b) institutional factors that allows GS relevant but non-public information (e.g., order flow) and they also generate information that is relevant (new product type things).
Part of that is relevant to trading activities but part is going to impact long term, investment results.