475 firms: Equation (3)

α

β

γ

Constrained OLS*

Estimated coefficients

0.30739

0.86769

0.13230

t-statistic

(0.319)

(18.868)

(2.877)

standard error

0.946

0.046

0.046

Constrained OLS*, with the constant suppressed

Estimated coefficients

NC

0.87708

0.12292

t-statistic

(24.857)

(3.484)

standard error

0.035

0.035