“…We use all controls variables as the matching criteria in PSM because these firm characteristics (e.g., firm age, leverage, OCF, etc.) can also impact the innovation output (Amore et al, 2013; David & O'Brien, 2006; Howell, 2018; Lee, 2020; Wu & Tang, 2016). We manually select the matched control firms and then rerun our baseline DID regression (Equation 1).…”