Control variables, methodology variation, and insignificance in empirical corporate finance

1. More fixed effect to control unobserved heterogenity among time, firms, industries.
2. Choose different variabels (e.g., profitability = EBITDA/AT or EBIT/AT)
3. Winsorize and trim
4. Model specification
5. Intercaction term
6. multiple hypothesis tests to decrease false positive
7. data cleaning, explore ratios in Compuststa database

Methodological Variation in Empirical Corporate Finance, RFS, Todd Mitton, 2022