effect having an opposite sign from the true effect. We present an expression for the asymptotic bias of both OLS and IV … estimators and discuss the conditions under which sign reversal may occur. We provide a method for eliminating this bias when …

, existing research suggests that online reviews often suffer from selection bias - people with extreme opinions are more … for reviewing has the potential to reduce this selection bias, because incentives can mitigate the motivational deficit of … voluntary reviews have a different distribution from incentivized reviews. The likely bias in the distribution of voluntary …